Chevy and GMC Duramax Diesel Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
why lower compression of your diesel when you start building power for racing

and why not have streetable 8 second truck if you have EFI

why not use multiple small turbos
 

·
Premium Member
Joined
·
2,905 Posts
if the comression is too high when you start adding a ton of boost, it will mostlikely blow... also allows for higheer rpms
 

·
Registered
Joined
·
2,899 Posts
Higher compression ratio with high boost is not good, it creates excessive cylinder pressure. The head gasket and bolts will never be able to hold it together.

8 second is not easy to run especially on a 7k lbs truck, you're gunna have to do alot of gutting.

Multiple small turbos will be good for the low end to mid range but will not be able to keep up the top end when running on big power, that's why they use large turbos for the upper end because it delivers more volume. Another reason is space.
 

·
Vendor
Joined
·
3,529 Posts
What would you consider "small" turbos that would get you into the 8 second range?

I recall IdahoRob mentioning he drove Max'd out on the street that runs mid/high 9's in 4wd form.
 

·
Stupid Has The Balls
Joined
·
2,515 Posts
why lower compression of your diesel when you start building power for racing

More RPM's and so you can increase boost without going :blowup

and why not have streetable 8 second truck if you have EFI

Because even strictly racing trucks including the fastest duramax can't do 8 seconds :rolleyes:

why not use multiple small turbos

You will starve the engine of air, they wont support like a big charger will
Hope this helps
 

·
Registered
Joined
·
915 Posts
why is the sky blue??
 

·
Stupid Has The Balls
Joined
·
2,515 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #8
thank you for answering my questions
and multiple meaning one per cylinder
 

·
DuramaxForum Veteran
Joined
·
4,506 Posts
thank you for answering my questions
and multiple meaning one per cylinder
the problem with this is packaging. it would take a lot of space.

The lowering of compression has already been explained. Simply to allow more RPms and more boost.

Many of the NTPA Pulling tractors run around 11:1 on motors that were at 18:1 stock. But they are also running in excess of 200psi of boost, and over 6500RPm on a motor designed for 25psi and 23ooRPm.
 

·
Registered
Joined
·
2,320 Posts
why lower compression of your diesel when you start building power for racing

and why not have streetable 8 second truck if you have EFI

why not use multiple small turbos
Try it and let us know how it turns out.:D
 

·
Registered
Joined
·
14 Posts
Discussion Starter #13
everybody thank you
 

·
Registered
Joined
·
622 Posts
why lower the ratio thought to run more boost wouldnt you achieve the same overall pressures between slightly more boost and regular compression ration as opposed to lower ration and more boost
 
1 - 14 of 14 Posts
Top