383 engine build, comp help
Thread Starter
Pro
Joined: Mar 2004
Posts: 508
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From: N.W. CT
383 engine build, comp help
Hey Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Hey Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
Why 8.5-9.0:1 SCR? I mentioned in your other thread that if you are keeping the boost low, I would be targeting 9.3-9.5:1 SCR.
Instructor
Joined: Jul 2009
Posts: 121
Likes: 0
You should also be able to get a -31cc dished piston.
Check out this Golen Build:
http://www.gmhightechperformance.com...all/index.html
Golen ports stock heads (52 or 53cc LT1, 58cc L98) hence the piston dish size and design.
I think conventional wisdom suggests that with a wedge head design (23 degree Small Block) you go for a flat top piston and let the combustion chamber dictate your compression, so I think the more detonation resistant path is this way as I believe detonation can start in the quench area. I do not really know if this is the case with forced induction, but it is the case with normally aspirated.
The hard core guys machine the piston dish to mirror the heart shaped head shape for the ultimate racing engines. I know that is not your case here, but I guess it supports minimizing the dish.
For what its worth I have a -21cc dish 355 and 8lbs and no problems, but you are building from ground up.
I would also think a call to AFR would give you a good recommendation.
Check out this Golen Build:
http://www.gmhightechperformance.com...all/index.html
Golen ports stock heads (52 or 53cc LT1, 58cc L98) hence the piston dish size and design.
I think conventional wisdom suggests that with a wedge head design (23 degree Small Block) you go for a flat top piston and let the combustion chamber dictate your compression, so I think the more detonation resistant path is this way as I believe detonation can start in the quench area. I do not really know if this is the case with forced induction, but it is the case with normally aspirated.
The hard core guys machine the piston dish to mirror the heart shaped head shape for the ultimate racing engines. I know that is not your case here, but I guess it supports minimizing the dish.
For what its worth I have a -21cc dish 355 and 8lbs and no problems, but you are building from ground up.
I would also think a call to AFR would give you a good recommendation.
Hey Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
I am building a 383 and I want to keep the comp at 8.5 to 9.1.
Dish piston options avalible to me are -12.8cc dish or -20.4cc reversed dome. 6.0 rod on -12.8cc and 5.7 on -20.4cc.
4.060 bore
head options 65cc or 75cc
Also what head gasket would I use for 12 lbs of boost.
What combinations
Example -12.8cc, .046 inch gasket, 75cc head, = 9.5 comp ration.
Any advice would help. Thanks Guys
Thread Starter
Pro
Joined: Mar 2004
Posts: 508
Likes: 0
From: N.W. CT
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Thread Starter
Pro
Joined: Mar 2004
Posts: 508
Likes: 0
From: N.W. CT
