383 head choice question
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Drifting
Joined: Apr 2002
Posts: 1,720
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From: Manhattan Beach Ca
383 head choice question
I want my next engine to be a stroked 383 but I was wondering if you still use stock heads (186) would you see much gain in torque and hp over a base 350? I dont know if I could afford new heads and my stock ones are completety redone but not p&p. Already have intake and cam.
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Re: 383 head choice question (Surfer69)
The rule is a certian amount of head flow cfm = a specific potential hp.
So with all things being the same except an increase of cubic inches. HP will stay the ruffly the same and only at a lower rpm peak and TQ will increase in a ratio simular to the additional C Inches.
Your main problem will be that your going to have to use dished pistons with the 383 to keep the C/R sub 10.0
So with all things being the same except an increase of cubic inches. HP will stay the ruffly the same and only at a lower rpm peak and TQ will increase in a ratio simular to the additional C Inches.
Your main problem will be that your going to have to use dished pistons with the 383 to keep the C/R sub 10.0
Melting Slicks
Joined: Sep 2000
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From: PITTSBURGH PA
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Re: 383 head choice question (gkull)
those 186 heads are worth 6-7 tenths over a set of smog heads and a afr 195 is worth 6-7 tenths over them 186 heads i know from expierience :cheers:
Melting Slicks
Joined: Oct 2000
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From: Heidelberg PA
Cruise-In V Veteran
Re: 383 head choice question (CORKVETTE1)
But, if you go with afr 195's - get the Competition porting.
if you decide later - it will cost you $1100. Ask me how I know this :D
if you decide later - it will cost you $1100. Ask me how I know this :D
Race Director
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Re: 383 head choice question (Surfer69)
A 350 and 383 of identical configuration (other than stroke, of course) will produce about the same peak power at the same mean piston speed, but the 383 will achieve peak power at lower revs because the power peak mean piston speed will arrive at lower revs due to the longer stroke.
The 383 will produce more peak and average torque over its operating range, and it will also produce more average power across the range, but it won't produce more peak power. Peak power won't necesarity be exactly the same, but the difference is not a signficant amount.
This issue is discussed in Taylor's IC engine textbook, and you can verify it with any simulation program by just varying the stroke on any engine configuration and observing the resulting power and torque curves
Duke
The 383 will produce more peak and average torque over its operating range, and it will also produce more average power across the range, but it won't produce more peak power. Peak power won't necesarity be exactly the same, but the difference is not a signficant amount.
This issue is discussed in Taylor's IC engine textbook, and you can verify it with any simulation program by just varying the stroke on any engine configuration and observing the resulting power and torque curves
Duke
