TB Blade and MAF Screen Mod?

[Mirage]

I figured instead of wasting 2 posts, I would just make it into one. Anyway, is the TB blade mod something I should do or not? I've seen people who love it and people who hate it, so what should I do? Also, What about the MAF screen mod? I have a cai and I'm not sure if I should remove the screen or not? What does it affect after you remove it? I know there are pros and cons to this as well, so just lemme know? Thanks

[Old Man]

"I've seen people who love it and people who hate it"

There are people that know what it doesnt do and what it effects and there are those who say they would never follow someone off the Empire State Building roof, but yet do this cause someone else did.

TB Mod- Your motor uses 322 CFM of air if it was perfect and ran a VE of 100%, but it isnt perfect so at 85% which would be real nice, it would use 273 CFM. Why all these numbers, well because your throttle bore as is with the plate can flow well over 400 CFM, actual numbers based on area size under vacuum shows 460 CFM. Removing the plate allow more air in on a lighter throttle useage< most think this is and increase, it aint, you just have less available throttle control. No gain in h.p., you only created a pressure drop that once its in WOT for a second or 2 it comes alive after ECM figured out what to do.

Screen is there to straighten the air flow out so that it more equally travels through the MAF. This equalization makes for a highly accurate read of air entering. Taking the screen out allows the air to pass through under alot more turbulence which then the MAF wont read accurately and the 02's after the fact tune for something that has now passed in happening. With the screen in place the MAF can flow over the 460 CFM allready mentioned that was more than enough to begin with and this same MAF is used on a 5.7 liter. Well somebody will bring up the fact that some newer engines do not use a screen, well those were bench flowed and tested without a screen so there calibration allready took the turbulence into effect!

[Mirage]

Well, I know everything is there from the factory for a reason and I shouldn't screw with it and since this is my daily driver. so I most likely won't mess with it. I was even thinking about taking off my cai and installing my old airbox back? You sound pretty knowledgeable, (sp?), so what do you think I should do about that? I may also drop a 355 in it several years from now, so I dunno if I wanna waste my time on anything else right now anyway?

[Old Man]

This is my 3rd 96+ 4.3 S series and Ive tried allmost all the CAI kits. The best one I used that I could confirm reallt did anything was the Volant. But that was way to high priced. For the price the AIRAID quick fit was farily decent. The K&N which is the favorite of most, did the worst in data logging test.
I run a factory modified box now and will change filter yearly and it does as well as the rest do. I posted up at the old site some filtering testing data which shows aftermarkets dont really do anything!

[Mirage]

Well, I have a generic K&N cai. I don't like it that much, basically because it's alluminum and too shiny for me. I may do the stock airbox mod, my stock airbox has a K&N in it at least..

[Kenny]

You're still full of it old man!

[Dimematters]

You're still full of it old man!
is that a joke or an insult?
If he's full of it give some proof?
If you are joking use a smiley :p ....

[Old Man]

If he's full of it give some proof?



Exactly or at least another solid theory!

[Kenny]

Heres a rundown of all the mods and the ET difference.
stock ZQ-8 with 750 miles 10.94
Royal purple oil& diff lube 10.68
modded stock box w/K&N 10.49
hypertech program 10.25
throttle body mods & descreen 10.06
Black magic fan & 160 stat 9.81
spiral core wires 9.73
MSD box and coil 9.82
flowmaster 40 9.88
pulleys 9.81
remove MSD and relace flowmaster with dynomax hemi super turbo 9.60
throttle body spacer no change
FIPK kit 9.12 final runs
Everything that worked stayed, the only things that didn't stay were the factory air box, MSD, Flowmaster and spacer.
I ran it 20k mi later after installing Transgo shift kit, iced the intake and nailed 8.99 NA it 8.6 with a 75 dry shot.

I'm sure Grey Ghost productions has video of all the races during '02. I'm sure some of you will say that knocking 2 seconds off the ET doesn't mean anything to try to prove your point..... The easiest way to prove it to yourself is to go to a junkyard and pick up a spare MAF and throttle body, do the mods to them and bolt them on, if it doesn't work for you, take it off! If you think the cylinders are gonna run lean, maybe you could look at the throttle body location on an LT-1, LS-1 or L-98.....maybe it's old school magic. My front cylinders did not run lean, no codes, no problems. the truck was getting 22 MPG. I did these same mods for about a half dozen of my customers and they absolutely loved it. Sooner or later you have to have balls enough to do it, if it doesn't work, do something else! My post was no insult or joke, it was a statement. What times are you turning? If the mods didn't work for you and you have data logging abilities, G-tech, and a local track, why didn't you give us the times???? I have the proof and probably a few hundred witnesses to what mine would do.

[Old Man]

Well lets see, I'll start with just a simple one. Go look at the fbody and vettes sites for people whom know.
That doesnt work, how about Myself, Kossuth, Geoff , a host of others and even the famous Bill Mach that all went through this descreen and found and average of a 7 h.p. loss on a dyno. All that info can be found in the archives of SSF!
Data logging also shows that a modifed MAF and a aftermarket read and average of 10%+ lower at the same TPS readings. Leaner can be quicker for a time until it adjusts, that I did say and have found along with a host of others.
Take a look also at the information at those Vette and F body boards about using MAF translators they came up with to remedy the situtation. They have all kinds of data loggin screens posted up that should the 02 adjusting a lean to zeroed postion. If you knew how the ECM uses short term data enteries for long term (WOT) tuning, you'd leave it alone.

Straight theory about air flows thats widely accepted by the aftermarket shows the defuser type removal will not do anything on something that doesnt need that air flow, but will do nothing but cause a pressure drop at a lower rpm versus before. You now have alot of pedal left that does nothing but move the TPS voltage.

Now as far as the track!! Track numbers really for the most part do not reflect much of anything as far as power production changes. You dont race for a living and dont do it consistant enough for it to bear any meaning.
You may go to a track after each mod and run to think you see what it does, but is it the mod or other factors since your not a professional racer.
That isnt and insult, but a fact, WHY?
Each time at the track you gain knowledge in some form or another.
Gaining confidence on racing in general
Finding new launching rpms.
Track conditions of adhesion and tire wear things
Outside condition factors

If you had raced for months every weekend with the same exact mods in place and found and average that would reflect the above which is by no means even close to complete, then add a mod and do the same amount of runs, then it would be more meaningful! I've seen people with the same car run month after month and drop over a second, why?

Its not and insult but a widely overlooked thing with the boards today. People have a wild fantasy about numbers, numbers dont mean **** unless theyve been given data time. Dynoes and tracks are inaccurate tools when used as a once per mod tool. There are too many varibles for them to have accurate meaning over a engine dyno which also data logs. Professional racers use data logging and nothing else to fine tune their vehicles. Times are not used because of the varible factory of conditions. Data loggin gains them the advantage of having conditions stores so they can maximize from previous runs what to do in a condition and will still learn from that day!

If a mod is suppose to do something, then data logging various sessions and comparing it to previous,will show the direction it went!

[Kenny]

Well, of course! Every test listed was a full night of test and tune, all test results are the average of at least 5 runs of usable data, any unusual abberations were always retested, there were none. All tests are corrected to the same altitude density, and all 60' times are between 2.09 and 2.19. I have been racing, setting up chassis and tuning for 20 yrs now, you asked for numbers and I gave you numbers. They are fact. They are consistent. and they are repeatable by anyone on this website, yet you will still argue emperical evidence that is undisputed? I understand that you have an opinion and I respect it, but you can't argue repeatable results that are documented in a professional manner with all variables taken into account. I am a racer through and through, and if something doesn't perform well I would not recommend it! The only people that argue the gains I have gotten is people who haven't done them, or did them incorrectly. :cool:

[Mirage]

I have no run times to give you! This is my only vehicle at the moment and I'm not gonna take it the strip and tear it to hell and not have another mode of transportation... I just wanted to know if these small mods were worth it or not? Also, the idiot junkyards I live around, won't sell seperate pieces off engines, it's all or none, just to get a MAF or TB...

[Kenny]

That's the good thing about someone else tearing into theirs, you can gain from that knowledge. If you want the parts, I can get you the parts. No sweat. You really don't have to do what I did to enjoy the extra performance. The throttle body mod by itself really improves part throttle response, thats something you'll notice every time you drive it. It just takes a systematic approach, no one NA mod will transform these engines. :cool:

[Kenny]

I have no run times to give you! This is my only vehicle at the moment and I'm not gonna take it the strip and tear it to hell and not have another mode of transportation... I just wanted to know if these small mods were worth it or not? Also, the idiot junkyards I live around, won't sell seperate pieces off engines, it's all or none, just to get a MAF or TB... My other post wasn't directed your way, it's just that me and old man have been beating this horse for a while, but those times will give you an idea of what gave me the most improvement so you can decide what fits your budget. Like the post says, I took it racing again after about 20,000 miles logged up and the times were consistent, after 60,000 it was running just as strong,but I sold it.

[Mirage]

Kenny, that's what I don't understand? Some people say the TB blade mod is awesome and others say it will hurt you performance, so what am I supposed to believe? Same thing goes with the MAF screen? Also, will it hurt the performance if I relocate the air temp sensor? Again, I've heard good and bad things about this as well? I want as much performance as I can get without tearing into the block or adding a supercharger.

[Kenny]

Amen bro! start searching around other sites also, It is hard to read people at first, but you'll start being able to figure out who the bull$h!++ers are!! I am always amazed at the length people will go to trying to disprove something they have never tried. The funniest thing is when my truck was new, K&N had pulled the original design CAI because they did not feel the numbers were worthwhile, so they redesigned the system and when they got the numbers they felt were acceptable, they released it. These guys put a lot of work into it! Anyhow, the throttle body mod absolutely works, the screen removal may or may not have helped, but it didn't hurt it either. I would say if you have reservations about the screen, leave it in. You'll do well, you seem to ask the right questions, it's just hard to wade through the answers. I've got some old parts around here some where. Maybe I'll start some kind of trade out deal like I'll send them to you if you promise to send 'em to the next guy who wants to try it. That way everyone would get the chance to try the parts out before they hack on their's........Hmmmm.
How's that for proving a point? Another thing to look at would be the plenum spacer that's out there.... It's on the Wynjammer site and Street & Performance, I've heard a couple of guys saying that these things rock! :D

[jrock262]

tb blade - resrtictor plate what ever

its fuel injection it doesnt have to be vacumed out of jets like a carb

the freaking thing is huge you can prolly make a roll of quaters out of it

not to mention another thing to get warm an hurt air tempture

why do u think nascar drivers like an dont like rescirtor plate races
kills power makes em bunch up together

but if you cant get more fuel in it than your running lean
after this mod buy a chip or hhp3 an intake

the screen is just to slow thing down
you wanna speed things up

i suggest keepin the thorttle body clean after this every oil change

theres guy waxin dumb shits 150 bucks just to remove it calling them performance thorttle bodys

[Old Man]

Kenny I guess you can entitle yourself to the opinion that it works. Theory, air flow data, data logging and strong willed have found it does nothing.

Havent tried it, oh yes I did. I got a bored throttle body (78mm), a deplated throttle plate and a intake spacer sitting in the metal junk pile out in the garage.
CFM tech got there idea of the plate from Myself and John Cannon years ago. We found it did nothing and caused a leaner front cylinder arrangement so it was scrapped.

78 MM bored throttle body was done in 1997 by myself based on the old stupidity of believing bigger was better. Worked on the 96 but gave me nothing I can now say. The 01 threw codes due to it since TPS to MAP and MAF readings were off!

Spacer under the plenum has been done between myself and another member. I'm a machinist and he wanted this spacer to add a fuel rail under the plenum for his swapped out injectors I added bungs for. Injectors did the job for his tune with his turbo, but it was tried NA to pin down the injector deal first before the motor was turboed. He reported absolutely nothing over the stock arrangement once he had the injectors calibrated for opening times.

Jrock, restrictors in NASCAR are added to a motor to reduce the bore size limiting air flow, but after its allready been figured and built for a X flowing carb. What I find funny is still this bigger is better, but if GM was adding this to hamper air flow instead of correcting a forward mounted TB intake, it would have been easier and cheaper to make the bore fking smaller in the first place. V-8 uses the same bore size and also the 8.1's of the day. Why would they if its hamerping a V-6 as YOU guys say??? <<< Just answer that one when the V-8's make 250-300 h.p.!

Kenny you still got a .1 in 60 foots that is a better gain than either mod, was that it????

[Kenny]

Thats great old man! Since you've got all the parts laying around the house and not using them, why don't you send them to Mirage so he can try them for himself? I'll pay the shipping! Let's get his shipping address, and shipping cost and I'll call your shipper with my bank card, pay shipping and throw in an an extra 10 bucks to help you recover your gas cost!!! Hear that Mirage? We just found a way for you to find out for cheap! SWEET ;)

[Kenny]

That was a .19 gain, and I'll take 2 free tenths any day, my 60 ft times were slowing as the tires wore and I was starting to make enough power to have problems with traction...... but your math skills seem to match your engine skills. Mine NEVER threw any codes, but I usually use gaskets and such on my stuff....maybe I'm too picky

[Kenny]

http://www.streetandperformanceelectronics.com/vmax.htm (http://) http://www.cfm-tech.com/chevy-vortec.htm[/URL] Check out these links. :)

[Dimematters]

I did both of these mods as well as relocating the air intake temperature monitor and cutting open the airbox. Doing all of those inexpensive mods i notced a very big improvement. I also noticed that over time it wasn't as strong of an improvement without me going through the trouble of reseting the computer.

[Kenny]

I did both of these mods as well as relocating the air intake temperature monitor and cutting open the airbox. Doing all of those inexpensive mods i notced a very big improvement. I also noticed that over time it wasn't as strong of an improvement without me going through the trouble of reseting the computer.
Excellent catch! I was told by a GM tech to reset the computer after each mod, after the truck was finished I never had to reset it again, but that would definitley explain why some guys are seeing a code. Good info! Thanks :cool:

[Old Man]

Resetting the computer only puts the computer back to its original tune and that alone should show you something. If when you revert back to the original tune and it runs as well or alot of times better its not because of the mod, it because you screwed the tune up. Once the mod was done it screwed the tune up and the computer hadn't adjusted, more times than not it went leaner and meaner, then it learned what changed. After time it went out of a learn mode and adjusted for the mod which even just stated died off. So much for that mod, isnt it! If a mod was to do good it would have continued to run that well all the time.

Now I prodded the numbers game for this next part. Numbers dont mean **** once they've been typed. ATI procharger came out with a kit built by someone else. They had a host of typed numbers up for a long time. I attacked those numbers with no compromising effort, why? They didnt add up not could they. 2 years later the whole thing drops like a heart beat and it was told at that point everything posted was just lies to protect what they thought was a buddy. All the numbers posted were projections and Gtech. Only one was a true track sheet out of over 20 numbers thrown out for track times. Not one was ever confirmed as a dyno run, ever. I had built a host of enemies and alot of these folks apologized in the own ways through PM's about there attacks. Your numbers dont add up. What I post could be lies, etc etc etc etc etc. Its the internet which is mostly used by, ah nevermind.

Now the real meat to digest, real fact for you's to fogure out what is truth and what isnt. First I'll start with and old quote from the org days in 1998. BUTT DYNOS are connected to loose noggins! I pretty much left this out only to add in morsels to see if anyone could pick up on them.

The MAF used on the 4.3 is the same one that is used on the 3.8, 3.8 S/Ced and the 5.7, pretty much everything under 300 flywheel. If it can fed those motors before GM goes to the 3 inch which then those motors exceed 325 h.p., how can the screen be a problem. A 350 at 100% VE uses 428 CFM and a 4.3 uses 322 and a SC'ed 3.8 would use 360ish!

The TB bore size is used on the 4.3,5.7 and the larger bore V-8. All have this socalled restrictor. The V-8s are half the size and it has 2 more forward cylinder than the V-6 does. All open toward the area where the injector pack causes air flow trouble and cut off the cylinders that dont have a problem. At its bore size its only slightly smaller than the LT-1 ones that are twin 52-56's in area size and area size determines the flow rate at X pressure or vacuum.

Large plenums are used for low rpm torque and if going continuely onto this ideal a larger plenum would do what, while it did what. Well it would gain bottom end at a lower RPM for upper RPM total air flow and power. Now we have a dyno sheet that shows upper RPM peak gains and a pushed up torque arena which is TOTALLY against the ideal of the large plenum!

Now also go into the forums and read sig lines of mods. If you look and really look and pay attention, the people showing the most codes by a long shot are those whom did these things. Codes to look for are random misfires, rich bank and lean bank codes, maf codes. All have done full tuneups which didnt stop the misfires. Alot have changed there injectors out for rich and lean bank ones and they still have them, why?

^^^^^^^^^^^ Now this information can been looked at and asked around from the dealer and so on for truthfulness and to summarize theory of ideals. Numbers and data typed can be skewed for anything and has allready been done so on boards. Which information do you chose to use?

[Kenny]

So does that mean you won't ship the parts? I'm so surprised............... :rolleyes:

[jrock262]

ok its fuel injection it doesnt need to be vacumed out of a jet .
an with a hpp3 adding more fuel an adavnceing spark timing it just stomps the pavement . i done this mod an it help so much better in the 60- an up

it would speed up intake velocity

it doesnt hurt performance

[Old Man]

If Mirage wants the MAF thats ported out and descreened which is everything but the electronics, I'll do it no problem. His decision, his deal, me free , just shipping.
Other parts, I'll have to dig up and see whats left.

Jrock, please explain how in YOUR theory that velocity is increased! Velocity decreases when you open a bore up, it creates a pressure drop.

Keep going guys, I love how you fight the knowns of air flow theories and .19 says according to theory a 20 h.p. gain, NOT! Every 1 tenth at 15 seconds is 10 h.p. Every one hundred pounds at the same 1/4 time, is .1.

Offer is still open to try to post these ideals and or read up on them at the Vette Boards and F body ones. See how far that gets you against a bunch of deep pocketed boys whom mean business!!

[Kenny]

If Mirage wants the MAF thats ported out and descreened which is everything but the electronics, I'll do it no problem. His decision, his deal, me free , just shipping.
Other parts, I'll have to dig up and see whats left.

Jrock, please explain how in YOUR theory that velocity is increased! Velocity decreases when you open a bore up, it creates a pressure drop.

Keep going guys, I love how you fight the knowns of air flow theories and .19 says according to theory a 20 h.p. gain, NOT! Every 1 tenth at 15 seconds is 10 h.p. Every one hundred pounds at the same 1/4 time, is .1.

Offer is still open to try to post these ideals and or read up on them at the Vette Boards and F body ones. See how far that gets you against a bunch of deep pocketed boys whom mean business!!That will be awesome if you would. Actually I'm one of the guys on the LS-1 sites, and since I own one, I guess I'm one of those deep pocket boys. And yes I do mean business. One will alsobe in my truck by springtime , I'm putting it back together now. Let me guess , a flow bench doesn't work either..... Ballsy bluff though!

[Old Man]

That will be awesome if you would. Actually I'm one of the guys on the LS-1 sites, and since I own one, I guess I'm one of those deep pocket boys. And yes I do mean business. One will alsobe in my truck by springtime , I'm putting it back together now. Let me guess , a flow bench doesn't work either..... Ballsy bluff though!


If you are a site member and I'm am even though no more Fbody in the driveway, you should know better. They hammered the MAF issue to death there over the years and its widely known to leave one alone.

OH a bench flow is gonna show alot more air on this MAF body I have, there is no doubt, the problem doing is as you should know reading MAF information on those sites it that it isnt calibrated to know its there and screws the tune up big time. Then even on top of that it screws with the shift points!

[Mirage]

Old Man, no offense and please don't be upset, but I have no clue what all those numbers actually mean...? :confused: I should be able to do the mods myself, I'm good mechanical wise on things like that. I just wanted to know what some good minor mods I can do, that would make it have a little better performance? Should I just save up for a supercharger and do that way down the road? I don't know. It looks like yall are arguing back and forth and I just don't know who to listen too? You sound like you know what you're talking about, but so does Kenny? And not many other seem to be answering, so like I said, I just don't know what's going on.

[Kenny]

If you are a site member and I'm am even though no more Fbody in the driveway, you should know better. They hammered the MAF issue to death there over the years and its widely known to leave one alone.

OH a bench flow is gonna show alot more air on this MAF body I have, there is no doubt, the problem doing is as you should know reading MAF information on those sites it that it isnt calibrated to know its there and screws the tune up big time. Then even on top of that it screws with the shift points! Go to LS-1 tech and look at the dyno pages, everyone who has balls enough to strap it on has ALL the mods I have been talking about, all the guys who have never done it talk it to death. Guys get on these pages to get solid advice, and the more you post,the more you get caught in your own bull$*!+. The only way Mirage will know for certain is to try it for himself,and there will be your proof, right?

[Mirage]

Well, damnit, I'm gonna try it next week. I should have my Programmer by then too. I'll try the TB mod, I'm unsure about the MAF screen one though, I don't wanna break something, I wasn't supposed too?

[Old Man]

This is from one of the major ECM tuners at the Fbody and Vette boards. No recalibration and your screwed, plus the fact he goes onto say HIGHLY modified again and again and again.

Some people are weak minded and will think anything works.


A few years ago Hot Rod Magazine ran an article on the proposed horsepower gain that could be had for free by the removal of the front and rear MAF Screens. Adding to the resulting screen removal frenzy are companies like GMS, PRO-M that offer the service of removing the screens and "gutting" the fins, again, for a reported HP gain.

The most critical note to be realized (that most don't) is that the engines that these were being used on were heavily modified.

The Myth: Across the internet and word of mouth spread the news of this "free mod" and countless pages promoted the technique of MAF Screen Removal without considering some very basic theories and the potential harm of doing this mod. Consequently time after time you will see the post and topics "I removed my screens - now Coding".


The Fact: The MAF Screen Removal Process WILL NOT CREATE horsepower within itself. It can only in the right conditions FREE UP horsepower that ALREADY EXIST and only under certain conditions.

Why?

1. Your stock MAF with screens will outflow your stock throttle body.
2. It will even outflow a 78mm throttle body.
3. It will also outflow your stock intake.

This Means: that if you are still using these stock components your MAF screen removal process is totally wasted and potentially dangerous and could cost $100.00 + if you screw it up. The MAF has to be the most restrictive element in your chain of flow to even possibly make the mod worth anything and ONLY if you already have the horsepower to free up by a modified throttle body and intake. Then the ECM must be calbrated for the new flow rates.



Are the Screens Restrictive?

Absolutely they are, but by design. Is your voltage regulator restrictive? Is your air cleaner restrictive? Is your fuel filter restrictive? Are your fuel injectors restrictive? Is your fuel pressure regulator restrictive? Yes they are.....by design. Would you remove your air cleaner or fuel filter? We are blessed with the common sense that although restrictive we find these components necessary for proper operation and to remove them would be foolish or asking for trouble. It is very unfortunate that we don't possess the same common sense regarding the MAF sensor.


Theory of Operation

Understand two terms first of all. Turbulent Airflow and Laminar Airflow. They are opposites. Without definition we can identify with "turbulent" but "laminar" airflow would define as "smooth, straightened out, regulated".

To help understand some conflicting articles I will point out an important factor here right away. There is no such thing as turbulence free airflow. Airflow is a "fluid flow" and a fluid flowing past obstructions, against boundaries, even the composition of the fluid itself in different densities and pressures create turbulence that can't be removed. So when we speak of Laminar Airflow being smoothed out and being the opposite of turbulent airflow we're speaking of a "controlled turbulence" vs. "uncontrolled turbulence".

Envision this process by thinking of your kitchen faucet. The little screen on the end. Take it out and watch your water flow increase but also notice it splash around and surge. You can see the uneven flow very easily. Put the aerator back in and see it smooth out in a more regulated even flow. Look at the end of most hair dryers and they will have a screen in them. Of course this is to prevent getting your hair sucked up in there and catching your head on fire BUT it also disperses the air in a more even, regulated pattern. Think of the construction of a dam on a river. You KNOW it is restrictive. It "holds back" the natural flow of water and regulates it to a desired given amount. Why? To do something productive with the process of flow. Just like your MAF screens.


The MAF Process

I am going to chop this section down to the most basic of processes. GM didn't invent this process, as a matter of fact it is the same process used by the weather industry to measure "chill factor" so it's theory was utilized by GM not invented by them.

1. You have a small wire inside your MAF which can be heated.
2. It is calibrated at zero airflow to be a certain temperature.
3. Air flowing across the wire cools it off. The more air flow the cooler the wire.
4. A voltage is supplied to that wire to keep it at a constant temperature. The more air flowing, the cooler the wire, the more voltage required to keep it the same temp.
5. This voltage fluctuation is a measurable, readable function which when converted to a digital output can be used for calibrations of airflow entering your intake.
6. These calibrations are referenced to a lookup table stored in your ECM and based on these fluctuations various functions of your engine are controlled based on the amount of airflow you are encountering.

The screens are there simply to provide a steady, stable, regulated environment for the most precise calculations available.

Now I will point you back to one of my previous "goofy-assed" examples and ask: Would it be easier to count the number of gallons that flow past a certain point in the river ...with the dam or without it? That is what your screens are for... to establish "near as possible" level playing field ground zero reference point for calibrations.


What Happens When They are Removed

Without the screen, the computer can not take a correct reading on how much air is entering the engine. When you port the MAF housing and/or remove the screens you are causing air to move by the sensors that is not being measured. Lower frequency outputs are being read by the lookup charts and the calculations are based on lower than actual airflow.

This makes the ECM lean out the fuel mixture, add timing, then cannot determine load changes properly, which could lead to transmission problems. Since it cannot determine proper load changes, shift points are moved around which could lead to tranmission failure.Then the oxygen sensors read the lean fuel mixture and bump it back up to compensate for the MAF sensors low readings.

In Summary I would say that I have heard of people making this mod and not having trouble codes. I have also heard of reported gains in performance. In both of these situations, if true, you have my respect and congratulations but I have never seen proof of these gains especially on a stock setup. I have however lost count of the number of post that are encountering trouble after making this "free" mod. Further I would say that if the horsepower is not there in the first place your sure not going to create any new horsepower cutting out your screens. And without proper tuning change you can create more problems than whatever gains you may see.

The MAF is a truly unique and awesome device that allows us to drive in different environments (altitudes) with no intake modifications. Allows us to make "other" performance mods without having to calibrate a new PROM. To butcher it and make it less accurate and precise just doesn't make sense to me.

1. If you are driving a stock intake car this mod will do absolutely nothing for you.
2. If you have such a heavily modified engine that it would make a difference Why are you using the MAF system anyway? .....you should be on Speed Density with a custom chip.

[Old Man]

This is from Mike a GM tech at ZR-2.com and also a LS1 guy.

So, do you really think GM put this part on the throttle plate to reduce the performance?

It is there to change the air flow through the intake to aid the rear cylinders by limiting the front cylinders. If you remove it and monitor the tempature of each cylinder, you will see how the air flow has been affected by removing it. You will have some cylinders run lean, and you will loose driveability.

[Mirage]

:rolleyes: I wouldn't think so, but I have wondered before.... I may not do it, I just didn't expect this thread to start a flaming war with everyone! I don't wanna possibly screw up anything, that would cost tons more to fix. I may just slap on some headers and an e-fan and then eventually a S/C or V8. Then, I can really screw something up, lol

[Old Man]

Not trying to make it a flame war, Kenny is!

If something is gonna work and it does and its been posted it does with some god solid backing I wont hesistate to tell you its good. If something in theory of how something should work and someone finds a better way around it, I'd support it.

If someone tries to tell you to ruin something, I STAND MY GROUND. I am here as a hobby to help those in need and protect those whom dont have the resources or money from getting robbed. I was young once and gullible just like anyone else, I had no where to turn like we have today with the net for debating and searching information out, so I can share things and so can others so we make good solid judgements of things.

These types of things bring me back to the Ricer thread at the old site in which I said there isnt really a Ricer problem, its a wannabe problem thats been around for years. Wannabes believe the unbelieveable, bigger is better and so on when you have to surpass what the current arrangement can provided before going bigger.

In the real world of performance there are no free mods, never has been, never will be unless some company decides to give stuff away free!

For those whom would like to see how tuning is accomplished and some other finer points I'll add 2 links.

http://www.ls1tuning.com/iboard/

http://www.ls1tuning.com/iboard/index.php?showtopic=749

[Kenny]

:rolleyes: I wouldn't think so, but I have wondered before.... I may not do it, I just didn't expect this thread to start a flaming war with everyone! I don't wanna possibly screw up anything, that would cost tons more to fix. I may just slap on some headers and an e-fan and then eventually a S/C or V8. Then, I can really screw something up, lolBest of luck Mirage! :D

[jrock262]

still 332 something cmf not true, i used a calculator for cfm an set the revs at 5500 an its says it needs 454 cfm an you said that the 5.7 takes the 450 somethin cfm every bodys know you but 650 cfm on a 350 for performance

[jrock262]

mirage go outside , pop the hood , take off the intake, crank the thorttle an look how huge that thing is . that thorttle body no matter what motor it is has the same dish , with the hpp3 giving more fuel you should make a big differnce
really in the 60 an up

[Old Man]

Jrock, do yourself a favor and shut your hole, pay attention and do some learning. I have a 16 year old that thinks he knows a few things also, but at least he listens.

322 CFM @ 5400 rpms is what the cylinders would use at 100% volumemetric efficiency. That is 100% unargueable, thats the math, period.
A 5.7 would use 430 CFM@ 5400 rpms, also unargueable. at 100% VE.

Not one motor will run 100% VE totally across and rpm range. No one has ever done that, allthough there are motors in smaller rpm ranges of the total range will. Our intake isnt going to allow it, it has to many problems to even get 80-85%.

Now you try to bring in old school numbers with carbs. Thats a different ball game since the sizing is not the same nor the reasons totallly for their sizing. 350's back in the day came with spread bore carbs for the most part. 450-550 CFM ones to be exact. People like me used to add cams to these and other work to take them from 5500-6000 RPM motors to up and over 7000 RPM motors.When you up the rpms you will up the CFM thats needed along with the fuel amounts. But this is another whole new ball game which I'm not going to get all the way into because it DOES NOT APPLY.

Now the HPP3, a stupid little toy.
Federal law, which to be in business and sell these as CARB compliant says you cannot go into the fuel curves and alter them under closed loop operation. Besides the fact they cannot on a handheld for one, second the closed loop section of the factory tune has locks in it which wont allow a handheld to do something like this.
What they do is alter the timing curves by falsifying the IAT to TPS and MAF curve. 87 octanes or step ones add one degree of timing to the curve. 89 tunes, 2 degress, step 2's and 91+ octane 3 degrees. On the fuel in only in PE (WOT) can they attempt a fuel change, its 5%, thats it. If you think that isnt true just look into the operation of a ECM. Its set to run 14.7:1 not matter what in closed loop. Thats and 02 sensor controlled item. I have never seen anyone ever that could remap 02 readings or even have a clue as to how. Now to add again to this, run the HPP3 unit for a few months, reset the computer to square one the proper way and tel me whats happens. I will tell you now cause I know what will happen, it'll run like a raped ape against what it just was running a day ago. WHY? because most of the changes the HPP2 unit did were caught by the ECM as being bad for emissions and it tuned it out, learned new trims and resetting it makes it go back and learn it again.

If you guys ever paid attention to anything, have you noticed how most 4 barrel carbs open in opposite directions! WHY, to push are to the front and rear runners of a better shaped plenum that still has the same problem. Yet you trying to tell me he defuser and rear ramped TB we have isnt doing that and the defuser is a restrictor to make you make less power.?????????????????

You have a set of heads good for 300 h.p. that cant be flowed enough better no matter what you do to justify the cost. 12-15CFM is all the best professional head builders can get outta them.
You have a TB bore allowing enough air in for 275+ h.p.
You have a MAF that will read and allow enough air for 275 h.p.
You have a cam ground only to allow well under 275 h.p., works at 1500-3800 rpm
You have and intake that pukes at 4400 RPM

You have every piece of info, links, theory etc etc etc all in front of you that was done either by professionals, GM itself and a host of others, yet you think you can do it one up better. You have no limitation in any part of the intake tract that will hold you under 275 h.p., yet you think you can one up that also. Talk about a ricer mentality!

[jrock262]

Rpm x displacement

__________________

3,456 = cfm


i know what im talking bout im 18 i know when it wont work or its pointless 2 do

[Old Man]

You have a CC motor and if you figure it out to cubic inches which is 1/12th of cubic feet, where does that leave you? Reattending math class again! Cause you sure dont have a cubic foot motor!

[Old Man]

262 cubes x 5400=1414800/ 3456=409 at 100% VE, 80% VE would be very good at 5400 and that it wont obtain, but we will say its so. 409x80%= 327 CFM

Since horsepower is a direct result of air and fuel mix combusting and at 4400 rpm a dyno run will show a 4.3 puking all over itself, it'll never be over 80% over 4400. The reason it dropped is it ran out of air.

So 262 Cubes x 4400=1152800/3456=333 x 81.48% <( % of 4400 against 5400)=271 CFM @ 4400

Peak horsepower RPM is where the motor will use the max air. The reason dyno charts fall off in horsepower is lack of air either by the cam profile or other things, which is a dropoff in VE. In our case its more the intake than the cam, but the cam wasnt designed over this rpm.

[jrock262]

i still get 454.86 , i didnt want to have to do this for you

262 cid * x 6000 rpm = 1572000 / 3456 = 454.86

[Old Man]

Cant get 6K, redline is 5400. Its not 100% VE and your and idiot!

[Dimematters]

This is one long thread...

Mirage, I will say again, I have done these mods they are helpful but the computer just retunes and then they are useless. I suppose you could find a way to reset the computer from the cab. MAybe with a bypass switch/breaker switch of somekind to disconnect and recconect the battery.

To answer your early question; YES just save up. a supercharger, programmer, headers, exhaust, and possible an electric fan. Would have you at roughly 275hp. The maximum that the 4.3's fuel system can maintain.

[Kenny]

Okay I was gonna just leave this alone but... Once the computer was reset after my last mod, it never needed resetting and the times and MPH remained dead consistent up to 60k miles when I sold it. The problem with the GM MAF usually comes from the owner over-oiling the air filter. To say that mixture distribution is a problem is just retarded. the reason I say this is that the deflector is only effective up to a max of about 1/3 opening. This mod is great for part throttle passing and such. Old man, you asked me to post numbers and proof and I did, you offered your theories again, you always make sure to properly chastise anyone who disagrees with you. You offer no real life evidence. Racers always tune at the track, the VE % and mathmatical have been shot to shit years ago, it only gives a starting point, the rest is up to testing data(reality). Again you pass misinformation about cylinder heads. The last set we finished did 272 in/198 ex(no test pipe)@ .500 valve lift VS 224/148 stock, all tested@ 28". What really stands out is, that as the expert you failed to mention that some of the late vortecs have a near 90 degree throat which have to be opened up to a larger valve size allowing a 70 degree throat for a good form to have the best low lift flow. Reading out of a magazine or book is fine, but sooner or later you have to test and prove your theories. I'll say it again Old Man, the more replies you post, the more obvious it becomes you have no practical experience. How many trophies and class championships do you hold? What times do your trucks turn? I know, I know just because it's faster......... doesn't mean it's faster, where you live. If you want to swap theories about Helmholtz tuning, infinite pressure waves,and chamber entry activation( swirl) that's fine, I can dust off the old engineering degree, but you need to get more accurate books to read before I'll bother. Or we could meet up, and I'll race you with my 93 TBI truck.....I'll spank you like a little girl!

[jrock262]

i dont have a tack in my truck but my moms bravada revs to 6 grand a lil bit passed then the limiter starts

hpp3 feture raise rev limter *

an all of our horse power is made at 5200 somethin like that

so the volume efficency drops at 4400

how do we make that 180/190 horsepower at 5200 rpms than ?

mirage worst than you can do with the maf is drop it , i used an razor to cut it an just peeled the rest off

[97zq8]

Hey Mirage, I've been reading what these guys have been saying and they sound pretty convincing, I know Old Man is serious about what he is saying because he has gone over this many times on s10planet a while back.

What Kenny has said sounds valid as well....
All I can say is, I did the throttle body mod and have run over 80,000 miles with no problems.

[97zq8]

I forgot to add, thats 80,000 miles over a 4 and a half year time period

[Old Man]

First we have Jrock and immature little punk spouting things he just doesnt know, or can even read. A factory 4.3 hp ratings are at 44oo rpms for peak, redline is 5400 and is locked by the ecm. SO just shut up!

Kenny is another jerk that is just spouting illbackable font. Anyone can type anything so we are to believe it.
Everything I have put up is on the net and available to all. From the air flow numbers and VE of motors, which havent been shot to death years ago or even today. The head data is from Quick Novas, Vortec heads, hi-performance chevy mag, Lingenfelters shop and a host of others. Nobody in there right mind would attack head that currently can outflow and power they are making or injectors that cant fuel what there limit is in the first place.
I too can run around pretending I'm doing all kinds of building from day to day claiming to be a bracket racer and the whole nine yards. You couldnt prove or disprove if I was or not just like Kenny, but again what I put up isnt just me typing like Kenny is, its on the net, magazines and so fouth which is proveable or not!!

Kenny I went through the same exact scenerio with Bill Mach and the ATI guys. They had all kinds of typing data and the whole shabag and in the end who was right???? The guys just typing or the sole one person that could readily take data from the net, mags etc and use it?? What you claim to be doing hasnt been accomplished by over 30,000 board members, so you now the new god?? Highly doubt it!!

[Kenny]

I'm kinda confused..... I was the one offering to prove what I can do. I kinda feel bad for you

[bill 4.3L 5spd]

ok i'm gonna lock this now,


mirage, old man has a maf he offered to send u for shipping that has the screen removed so you dont have to worry about messing yours up/not liking it.

i will say this i gutted the maf and ended up going back to a stock one and the truck runs 10x better than when i had the gutted on there.

i did the tb plate mod and i liked it but want to try a stock one for a bit see if i notice a diff