turb'ed 455

Making Boost

QIKAZEL
Joined
Jun 18, 2006
I was wondering how much hp a 72 455 block could handle. Would stroking it out lessen the strength. I was kicking the idea around but I want to at least keep it all buick.
 
I'm no expert by all means but I wouldn't think it would be any stronger than a chevy small block. Even they need a little help with just conservative boost and blowers, although you can get by without. If I remember right all the production 455s were all 2 bolt, I think, maybe its pontiac I'm thinking of:confused: . Anyway I would think TA performance could help out if no one here has the answer-but I'm sure someone does;) A built 455 would be killer-a turbo running with about 6-8 lbs would be the cat's @ss! Gotta get out of here, I'm starting to brainstorm naughty things for my limited:eek:
 
455

The main webs on a buick are very thin and are prone to breakage. You would definitely need to girdle it. The main journals were increased to 3.25 by Buick engineers to add stability to the weak thinwall block castings. Later 74/75 blocks are much stronger and have less incedence of core shift. You will still need to girdle it though. Also the oiling system on those motors are poor at best. For a wealth of knowledge pick up "How to build high performance engines" by Steven Dove Hope this helps I messed with one of those motors before buying my LSX
 
Close, the 75-76 block are the stronger ones with the 5/8" oiling. There are roughly 4 generations of BBB's. THe 67-69 400/430 blocks, the 70 and 71 which are near the same just with oiling through the pushrods instead of the deck, 72-74, which have some improvements but not a whole lot, and the 75-76 blueblocks that have the better oiling, more nickel, and heavier walls.
 
Also, don't forget the 75-76 455s have ultra low compression!

With a set of forged pistons, low compression = more boost allowed, right?

Not sure, I'm new with the turbo thing. I'm not new with the N/A Buick thing, though, and I've got a 76 455 that is going to get it!!
 
75 and 76 have the most ping and detonation prone heads ever made on a Buick. They are huge open chambers with 0 quench. You'd be better with a set of '74 heads and be careful on the piston selection. The best way to do it is custom forged pistons and some of the early heads or the new Aluminum heads from TA or Edelbrock with the smallest chambers as possible and put all the volume in the piston so you have the greastest movable surface area.
 
Isn't that simply corrected by polishing the chambers and creating the heart shaped contoured chamber? That, along with flat faced valves (instead of scooped out tulips) and a mild shave should make them good pieces, right?
 
I was wondering how much hp a 72 455 block could handle. Would stroking it out lessen the strength. I was kicking the idea around but I want to at least keep it all buick.

Hot Rod mags featured a bandit car with twin turbo 455 fully streetable in the low 9s check it out.
 
My trans builder is running mid nines w/ his gs. His shop is trans pro out of lansing IL. 1-708-895-0003 he is running n/a no power adders.
 
Isn't that simply corrected by polishing the chambers and creating the heart shaped contoured chamber? That, along with flat faced valves (instead of scooped out tulips) and a mild shave should make them good pieces, right?

Not even close. An open chamber means that the chamber walls are as wide as the cylinder bore. To "close" an open chamber you'd have to weld in the chamber and then remachine them to a closed chamber profile. Flat faced valves will help marginally with chamber volume but not really a lot. Shaving the heads would help but I don't know how thick the decks on the heads are and you need rigid heads to contain booste. Get better heads, a set of 72-74 shouldn't be expensive since they are aren't very desireable.
 
I apologize, I probably wasn't quite clear enough.

I meant to say this, "Won't the polishing and reshaping fix the pinging/detonation/zero quench problem?"

I'm not going to shave the heads out of this world, just enough to flatten them. I am going to use these heads first just to see what I can get out of them. I have some high compression 430 heads I can use later.

So, what do you think about the pinging problem? Why are these heads prone to that?
 
Open chambers create little charge motion. No charge motion means little detonation resistance. Pinging is spark knock, you have too much timing for the chamber. I'm no expert on how to fix these issues, just know what they are and some of what causes them.
 
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