Shorty headers
#3
Le Mans Master
Member Since: Oct 2002
Location: Las Vegas - Just stop perpetuating myths please.
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Summit racing only shows one mfr of shorties for your car - Hedman. Though i'm sure there are others. But Hedman does make good headers - i like'm. And let me say any headers with separate tubes is gonna be better than stock manifolds as the separate tubes can provide some amount of scavenging where cast manifolds can't and create backpressure on adjacent cylinders.
I my book exh tuning is a full science by itself and most cannot afford to fully optimize it - just to much detail and effort. Maybe a sponsored race team with a generous dyno budget but not any hobbyist.
Hope this helped.
#5
Drifting
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I know short headers are not great but there are some better ones than the stock ones.I have to keep the cats on my Vette so I'm not expecting a lot,Just better. I have not Seen the Hooker iron one who carry's them?Thanks for the reply's guys.
#6
Team Owner
I have the stock cat but NOT the precats on my 91. Using TPIS long tube headers. Do you have to keep the pre cats or just the big one?
#7
Team Owner
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C7 of the Year - Unmodified Finalist 2021
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I'd generally say that they are not worth the expense unless you live in Commiefornia, but i don't know who makes anything useful anymore either.
If you don't have to pass a visual but must still pass smog then you could put in a better dual system front to back and use new cats, and you will likely still pass smog if the engine is heated up before you go over to the tester.
If you don't have to pass a visual but must still pass smog then you could put in a better dual system front to back and use new cats, and you will likely still pass smog if the engine is heated up before you go over to the tester.
#9
Race Director
Don't know what block you used to build your 400 or what config you "need" for AIR hookup.
That said:
https://www.corvetteforum.com/forums...hlight=headers
That said:
https://www.corvetteforum.com/forums...hlight=headers
#11
Melting Slicks
[QUOTE=856SPEED;1593578999]
I was told headers are optimized for a certain RPM to achieve optimal exhaust pulsing for scavenging (or not) at that RPM. Design considerations include volumetric flow, too. A pal did SEMA testing long ago and actually proved that too-large tubes actually decreased power output because of lost velocity (reduced scavenge).
Shorties, I believe, offer little if any advantage over stockers, as was said in the cost/benefit posts. I had a set of short SLPs, long ago, but sold them before mounting.
I was told headers are optimized for a certain RPM to achieve optimal exhaust pulsing for scavenging (or not) at that RPM. Design considerations include volumetric flow, too. A pal did SEMA testing long ago and actually proved that too-large tubes actually decreased power output because of lost velocity (reduced scavenge).
Shorties, I believe, offer little if any advantage over stockers, as was said in the cost/benefit posts. I had a set of short SLPs, long ago, but sold them before mounting.