What do ya'll think?

[Telemarshallman]

My Uncle recently gave me a 1986 Buick regal with a newer 305 SB (40k mi). First off I know nothing about buicks. I know I like Grand Nationals but thats another topic and another motor.

I was wondering if you think it would be worth it to try a swap with a 305. I don't have any funds to modify the motor other than exhaust headers and a vette radiator so if I put it in my truck it will still be a stock 305.

Also, I haven't heard much about Buick V8s. Is this because it is the same as a Chevy V8 or is this because it sucks? Does anyone know if the regals came with a 700R4 or something else.

[steve]

I think it is the same as a chevy 305. And I don't think it is worth your time and effort doing that swap unless your truck has a bad motor already and you are going to use the 305 for only a short time with future plans of putting a 350 in it. The 305 never impressed em much, but what the hell do I know I am crazy enough to build a 2.8 stroker.

[Telemarshallman]

What all would it take to turn a 305 into a 350 or a 383? Wouldn't a 305 boared out .30 = a 350 (with new pistons and such) so then couldn't I use a 305 block boared .30 and a 400 crank to make a 383?

It would be a project then, but I think I can find all the parts I need rather cheap at a junk yard, and I know of a couple good machine shops around here.

Something to think about I guess.

[67Truckin]

Go talk to your machine shops and get their opinions on a buildup for the 305. I thought HotRod did a stroker on the 305 but I don't remember what cubic inch they ended up building. I think they used 6" rods, forged custom pistons and a special ground stroke crank.
I don't believe the 305 can be made into a 350 due to cylinder bore size. All 327 and 350's use a standard 4.00" bore.

[Danny_SS]

no you cannot just bore a 305 to make a 350. The difference in bore is a lot bigger than.030". besides tha 350 crank is different.
You are better off finding a 350 and work on that if you want a 350.

[mdmilburn]

modifying the 5.0 liter tbi v-8 (http://www.goingfaster.com/spo/modthel03.html) this site really shows how the 305 can shine but it needs a T.B.I. to do it

[mdmilburn]

http://www.goingfaster.com/spo/modthel03.html this site explains the potentail of the 305

[mdmilburn]

try this one http://www.goingfaster.com/spo/343hp305.html from what i can gather the heads are the main down fall for high rpm power but there torqe potential and m.p.g. are hard to beat for a v-8

[steve]

Don't the 305 have 2 bolt mains? And you are talking about 300-400 horsepower out of a 2 bolt main engine? That sounds like a bad idea. I do not know the exact stress load those 2 bolt mains can take, but I would bet you are pushing them pretty hard by putting 300+ horses to them.

[mdmilburn]

information is power er is that knowledge ...........how many big block chevys from the first ones in 1965 on up through the years easly made that stock from the factory with 2 bolt mains

[big dave]

With a little care in assembly, you can easily push a 2bolt main smallblock to 500hp safely; some folks even take them up to 700 or so (they're cheaper and it's ok if they blow up after the race)

[alscrimp]

The 305 and 350 small block crank are the same. And yes a 2 bolt main will hold up to a 300-400 horsepower engine if properly built for it. I use to race one. You can also bore out a 305 .125 to make it bigger. The problem areas of this 305 are the heads. This was designed to be a "smog (emissions)" engine, not horsepower. but with a few modifications it would be a worthy opponent.

[jkrick]

i beg to differ on the crank being the same. i can tell you for a fact that the crank is not the same in a 305 to a 350.

[Danny_SS]

the 305 crank IS NOT the same as the 350 crank allthough they both do have the same stroke.
A big problem with the 305 is that since the bore is smaller you cannot fit most performance heads with 2.02" valves and a Big cam or the valves will run into the cylinder walls.
If you have a 305 and you do not want to sell it and you do not really want too much power from it then a 305 is ok, but if you want power in the 350-400hp level then it will be best to have a 350. 2 or 4 bolt main does not really matter.

[Dimemaster]

If you have the 305 and want a V8, go for it. 305 beats most any stock S10 engine, anyway. Further down the road you can shop around for a 350 core, build your 383, and swap it in.

Forget building a 305. While it IS possible to make a 400hp 305, it's so much cheaper to build a 400hp 350 you can buy the 350 core and still have money left over.

2-bolts are fine until about 400hp/400lbs/ft. More than that and bearing life decreases exponentially. You probably could build a 2-bolt block that would make 700hp. Once. And very briefly before spinning a bearing or breaking something.

That said, I build all my smallblocks starting with used 2-bolt blocks. Sonic degrease, solvent flush, rod, solvent flush, sonogram, magnaflux, deflange, true surfaces, center bore with torque plates, Milodon splay-bolt 4-bolt mains, main girdles, align hone, screw-in oil plugs, brass freeze plugs, chase all threads, solvent flush, paint outside only.

Good enough for 750hp engines in a off-road unlimited trucks that have to live 1000 miles, or 60,000+ miles of being beaten as a 460 hp street/track roadrace engine that gets the occasional 225 shot. Yes, you can make big power from a 2-bolt block, but expect to fork over $2,500 or so to prep one.

[steve]

I stand correct about the 2 bolt mains. I was always under them impression that if you plan on building a motor over 300 horsepower or so and driving it hard and often, you would want 4 bolt mains for durability. The 2 bolts would not hold up on the long haul. But I guess I am wrong.

[Dimemaster]

I don't think you understand. 2-bolt mains will not hold up to high rpm and/or output because they allow the crank to flex, meaning the bearings wear very quickly and either a main spins or the crank breaks. The block usually doesn't weaken up enough from the flexing to break until 3 or 4 cranks have broken in it.

My high performance engines begin as 2-bolt mains and are converted to 4-bolts, and the bolts are not parallel. In a race engine, a 350 built from such a block can easily turn 10,000rpm and more. This is well beyond the capability of a factory 4-bolt main production block and a little beyond the capability of the nodular iron block with straight mains. A nodular iron block with splay-bolt mains and a girdle is the strongest of all. Figure about $6,000 just for the prepped block, and that's pretty much a requirement for a 1,000hp 350.

I once built a blown 302 with splay-bolt mains and that sucker was shifted at 11,600rpm. Peak horsepower was right at 940 or so. It ran Sunoco 260, 106 octane, with alcohol injection to cool the intake charge. Also, the intake manifold was packed with ice before each run. The engine was used for several years in a number of Bonneville cars, and beat several class records with first runs into the wind, but never managed the required backup runs without breaking something. The longblock was never a problem, but the car owner was.

The only time I use 2-bolt mains is when building an engine like Yesenia's 268. It isn't going to make all that much horsepower, 240-250hp@3800, 270-280 lbs/ft@from 2000 to 5500rpm, so anything more simply isn't going to make a difference.

[steve]

Dimemaster I wrote that post before I read yours. I understood your first post and how it back up my belief that 2 bolt mains were not strong enough to support high horsepower reliably.

[Dimemaster]

Okay, sorry. I apologize. Old habit. Just keep in mind that there used to be this guy named "steve" that came in here and didn't have a brain or something. He actually believed anything he read on the internet, if he wanted to believe. I kind of miss him because he was so much fun to abuse. Obviously, you're not the same guy because you know how to spell, capitalize, punctuate, and string together two thoughts in a coherent manner. Maybe Mike will let you change your knick to "new steve" so we know it's you.

[steve]

Is that good old A-Hole Dimemaster back??? Just when I was starting not to despise you, you had to go and screw it all up. And just to let you know… I choose not to reply to any of your posts that I believe to be B.S. (there has been a lot of them) or just wrong in general (been a few of them too). Because I decided you are not worth an argument. For that reason I am no longer going to reply to this thread.

[Dimemaster]

Welcome back, steve. BWAAHAAHAAHAAHAA!!!!!

[eriks98s10]

Dimemaster, what do u mean your main bolts aren't parallel? You mean like the bolts on one side of the cap are like adjacent to each other? And that strengthens the caps so the crank wont flex while it's spinning, right?

[Dimemaster]

All 4 bolts for one cap are still in a line. The two inner bolts in each main cap are just like the factory 4-bolt caps, perbendicular to the block/main cap mating surfaces. The heads of the outer bolts are tilted in towards the crank. The two outer bolts are tilted almost parallel with the outer wall of the block. This pulls the lower portion of the block together and reduces cracking of the main webs. Not necessary for less than 600 horspower, though.