What heads came on 89 350?
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From: okiehoma
Car: 1970 Chevelle SS 396
Engine: 414ci Big Block Chevy
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What heads came on 89 350?
Whats the casting number for the heads on a 89 Iroc 350 TPI? They were never changed so anyone have an idea?
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The full number is 14101083. For reference, the 87+ 305 TPI heads are 14101081.
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They're stock heads.
There's LOTS of variation from one head to another, and one cyl to another. Even if you got "the flow numbers" that somebody else measured, there's no way to know that they're the same as yours. Or really, even very close.
Most of them flow in the very low 200s (like 200-205) on the intake and high 130s to low 140s on the exhaust.
There's LOTS of variation from one head to another, and one cyl to another. Even if you got "the flow numbers" that somebody else measured, there's no way to know that they're the same as yours. Or really, even very close.
Most of them flow in the very low 200s (like 200-205) on the intake and high 130s to low 140s on the exhaust.
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Originally Posted by GreenChevelleSS
Thanks guys,
Anyone know where to get the flow numbers for them?
Anyone know where to get the flow numbers for them?
Looks like sofakingdom was really close with his recollections. I'm not sure how the iron head compares, but the aluminum L98 head doesn't seem to be the greatest performer, even for stock heads... (You'll need to scroll down a bit)
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From: okiehoma
Car: 1970 Chevelle SS 396
Engine: 414ci Big Block Chevy
Transmission: Muncie Turbo Hydromatic 400
Thanks guys The Desktop Dyno's not real accurate anyway Id just like to have an estimate at what we are hitting. Ill use the flow numbers for the aluminum and reduce it alittle to get about what the cast Iron heads should be.
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Re: What heads came on 89 350?
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Re: What heads came on 89 350?
Sbc pattern will bolt up on exhaust side. But if the headers were in a different application no they won’t work
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Re: What heads came on 89 350?
side note: I can’t believe someone actually responded since this forum is from like 15 years ago haha.
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Re: What heads came on 89 350?
The 083 heads are very modest in stock form.
But get very good when fully ported with bigger 2.02x1.60 valves.
The lowest cylinder head parameter in DTD models a stock 083 head. Flow is just under 200 cfm stock.
can go 235-240 ish full port w/1.94" valve.
Can go 260 cfm w 2.05 and full effort port.
If you want to go fast spend your time porting the heads not playing on DTD.
But get very good when fully ported with bigger 2.02x1.60 valves.
The lowest cylinder head parameter in DTD models a stock 083 head. Flow is just under 200 cfm stock.
can go 235-240 ish full port w/1.94" valve.
Can go 260 cfm w 2.05 and full effort port.
If you want to go fast spend your time porting the heads not playing on DTD.
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