Long tube header fit and performance
#1
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St. Jude Donor '07
Long tube header fit and performance
I am looking for information on how long tube headers fit on C4 LT1 cars. Specifically will the headers hang lower than than the stock exhaust system?
This is a T-1 car that sits very low already. I would not want to make the lowest part of the car the header pipe.
Also what kind of hp differences are there between long tube and shorty headers?
Thank you,
JOHN
SPDZONE
This is a T-1 car that sits very low already. I would not want to make the lowest part of the car the header pipe.
Also what kind of hp differences are there between long tube and shorty headers?
Thank you,
JOHN
SPDZONE
#3
headers
hi, i have the em long tube headers and the fit is great. i got the ones without the air tubes. i was able to put the car on 4 stands and the headers went right up through the bottom of the engine compartment with no problems. one thing i did was to turn the left side engine mount bolt where the nut is in the front for tube clearence. they do not hang below the engine. my car is lowered also and i have not hit anything that would dent the headers. i used the solid copper gaskets and torqued all of the bolts to 28 ft/lbs. you can even remove the starter with ease. see ya
#5
Melting Slicks
hi, i have the em long tube headers and the fit is great. i got the ones without the air tubes. i was able to put the car on 4 stands and the headers went right up through the bottom of the engine compartment with no problems. one thing i did was to turn the left side engine mount bolt where the nut is in the front for tube clearence. they do not hang below the engine. my car is lowered also and i have not hit anything that would dent the headers. i used the solid copper gaskets and torqued all of the bolts to 28 ft/lbs. you can even remove the starter with ease. see ya
#6
Melting Slicks
Not to hijack the thread but Hooker heads fit finish and added noise and heat in the cabin??? Thinking of the painted comp ones no air fittings?? The Borla exhaust sounds great but getting to the limit for a cruise over 100 miles..
#7
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First you need to decide your needs, a stock engine or near stock will get better performance w/ 1 5/8" primaries and a medium to heavily modded engine will do better w/ 1 3/4" primaries.
I have Hedman elites and love them, my car is stock so that is why I went with 1 5/8 primaries.
If you have a auto, you will might have a problem. I kept my stock catback system and put hi-flow bullit cats on and used a 3" connector pipe and welded it on.
I would suggesst what ever you do that you weld the system, everybody(including me) that tried to use ubolts, had leaks.
Hope this helps, also do a search. I saw a million and one threads on this subject.
I have Hedman elites and love them, my car is stock so that is why I went with 1 5/8 primaries.
If you have a auto, you will might have a problem. I kept my stock catback system and put hi-flow bullit cats on and used a 3" connector pipe and welded it on.
I would suggesst what ever you do that you weld the system, everybody(including me) that tried to use ubolts, had leaks.
Hope this helps, also do a search. I saw a million and one threads on this subject.
#9
Melting Slicks
First you need to decide your needs, a stock engine or near stock will get better performance w/ 1 5/8" primaries and a medium to heavily modded engine will do better w/ 1 3/4" primaries.
I have Hedman elites and love them, my car is stock so that is why I went with 1 5/8 primaries.
If you have a auto, you will might have a problem. I kept my stock catback system and put hi-flow bullit cats on and used a 3" connector pipe and welded it on.
I would suggesst what ever you do that you weld the system, everybody(including me) that tried to use ubolts, had leaks.
Hope this helps, also do a search. I saw a million and one threads on this subject.
I have Hedman elites and love them, my car is stock so that is why I went with 1 5/8 primaries.
If you have a auto, you will might have a problem. I kept my stock catback system and put hi-flow bullit cats on and used a 3" connector pipe and welded it on.
I would suggesst what ever you do that you weld the system, everybody(including me) that tried to use ubolts, had leaks.
Hope this helps, also do a search. I saw a million and one threads on this subject.
#10
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Adding a comp cams XFI 268 1.6 rockers custom intake GM fastburn heads have 3.07 gears but stock converter Borla exhaust magnaflow cat. 1 3/4 is needed to fit exhaust port alone.. I am looking for 400 to 425 at the crank under 6k rpm and hope it can be done without pulling the engine. I guess a we shall see thing..
Not to duspute you, but 400-425 hp from a L98 w/your mods seems high. 140+ hp gain w/bolt on's is a lot, but I guess it is possible, do you have stock injectors?
Also, were did you get those gear? Or are they stock, need to get rid of my 2.59's.
Almost forgot, OP after headers get a tune. Will help you get the most from your mod.
#11
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I didn't know any better about the heat and mine melted the brake booster, put a heatshield over the nbr 5 and 7 primaries so you don't do this.
#12
Melting Slicks
Thanks for the tip did you make a stainless heatshield or use header wrap? To the previous on poster the only parts i will have left that came with the engine is block crank rods and pistons and making me now wonder why not a 383 or 406... I did not want to pull the engine and starting to think it might actually save time than add to it...
#13
Melting Slicks
"Also, were did you get those gear? Or are they stock, need to get rid of my 2.59's. "
The 3.07 gears were a factory option I am not sure of the RPO code but sure someone here is up on it.
The 3.07 gears were a factory option I am not sure of the RPO code but sure someone here is up on it.