So how do you determine how much boost an engine can handle?

[WishIHad$$$]

I assume it has something to do with the materials made, cfm, displacement, etc. I would like to know if there are any formulas for a project I am doing. Please don't respond with "trial and error", I can't afford to buy two engines. [img]tongue.gif[/img]

[phoenix64]

All engines have millions of tiny flaws, and each engine is completly different. Some 3.8's will hold 600hp stock. Some will die at the 200hp level. Only way to find out for sure is to break it.

As a general rule with 3.8s anything over 9psi creates lots of blowby. 6psi is fairly safe though.

You can get away with more boost if you run an intercooler, and/or higher octane fuel.

[WishIHad$$$]

I'm not looking at the 3.8L engine.

[phoenix64]

Well in that case pick up Corky Bells book, it has some really good sections on increased engine wear, as well as some tables that relate Compression ratio to maximum boost pressure and octane of your fuel.

[White95]

If it makes you feel better I plan on running 10-15+psi of boost on a T70 turbo which will put my little 3.4L some were in the 400+HP range

[Turbo V6 Camaro]

when you brake it down it all come down to chamber PSI. to high and one of these things will happen

you'll lift the head off the block, blow out a gasket, crack your pistons and/or shatter rods/crack, or have some vavle flow and show vavle through the head lol

[Jerriko's Garage]

Originally posted by phoenix64:
Well in that case pick up Corky Bells book, it has some really good sections on increased engine wear, as well as some tables that relate Compression ratio to maximum boost pressure and octane of your fuel.

Any idea where I can get a hold of this book?

[AlienInv8r]

Book store, it's a pretty common book for just about any decent sized book store to carry. Amazon and other online bookstores have it too

[Jerriko's Garage]

Originally posted by AlienInv8r:
Book store, it's a pretty common book for just about any decent sized book store to carry. Amazon and other online bookstores have it too

Cool, thanks. I will have to check that out.

[Arctc Wolf]

depends on a lot of stuff. Most important, compression ratio and fuel octane. too much compression or too little octane and you'll get detonation. other things such as cam(design, specs, ect.), heads(ported/polished, thermal coated, cryo-treated), pistons(forged, cryo-treated, thermal coated), crank/rods(cryo-treated, balanced, shot-peened), spark plus(gapping, heat-range), intake manifolds(ported/polished, gasket matched), exhaust manifolds(port matched, low-restriction), as well as other little things will affect the amount of boost you can run. usually, a motor with a better flowing top-end can hndle more boost, lower compression and higher octane can handle more boost, and cryo-treated parts can handle more boost.

[Turbo V6 Camaro]

its not they canhadle more the can take more abuse

long as you don't KR thats the big killer and high temps from heat soke hurts too and cause's KR

you can only fit so much air into so much space, sometime something is going to give lol

RPM is a big factor too

if engine speed is increased 3 fold, the internal load is 9 times as great!

- corky bell

[Mighty Thor]

A non-intercooled has done well at 9psi. but above that, it gets dangerous.

With the intercooled one you could go 10-12 and still be OK.

Anything above that on a stock engine, you're pushing it.

[WishIHad$$$]

Thank you for the replies. I should've picked up "Maximum Boost" and read it before I posted [img]graemlins/stickpoke.gif[/img] but I will be getting it in a few weeks.

Oh, and for the confused people who don't read, this is not for an L32 or an L36 engine :mad: [img]tongue.gif[/img]

[Turbo V6 Camaro]

Originally posted by WishIHad$$$:
Thank you for the replies. I should've picked up "Maximum Boost" and read it before I posted [img]graemlins/stickpoke.gif[/img] but I will be getting it in a few weeks.

Oh, and for the confused people who don't read, this is not for an L32 or an L36 engine :mad: [img]tongue.gif[/img]

natures laws apply to all motors

[WishIHad$$$]

Originally posted by viper04af:
</font><blockquote>quote:</font><hr />Originally posted by WishIHad$$$:
Thank you for the replies. I should've picked up "Maximum Boost" and read it before I posted [img]graemlins/stickpoke.gif[/img] but I will be getting it in a few weeks.

Oh, and for the confused people who don't read, this is not for an L32 or an L36 engine :mad: [img]tongue.gif[/img]

natures laws apply to all motors </font>[/QUOTE]

Originally posted by Mighty Thor:
A non-intercooled has done well at 9psi. but above that, it gets dangerous.

With the intercooled one you could go 10-12 and still be OK.

Anything above that on a stock engine, you're pushing it.

[img]graemlins/stickpoke.gif[/img]