L98 Headers
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
L98 Headers
OK, I am thinking of throwing a set of headers on my L98 as I hear this is the FIRST improvment that makes sense on these motors.
A couple of questions:
1. Will any small block headers work?
2. How hard are they to put in? Do you go from the top down of feed from the bottom up.
3. will they line up with my existing cat back system I already have installed, will I have to make any mods to this system? It's a Power Effects system, and I like it.
How hard a job is this? I've done exhaust before, Just never on a C4. Figure I am 1/2 competent with enough tools to be dangerous and some decent knowledge about engines and such.
A couple of questions:
1. Will any small block headers work?
2. How hard are they to put in? Do you go from the top down of feed from the bottom up.
3. will they line up with my existing cat back system I already have installed, will I have to make any mods to this system? It's a Power Effects system, and I like it.
How hard a job is this? I've done exhaust before, Just never on a C4. Figure I am 1/2 competent with enough tools to be dangerous and some decent knowledge about engines and such.
Thread Starter
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Originally Posted by bill mcdonald
1. no, they need to be for a C4
2. not too hard. Feed from the bottom up.
3. I highly doubt they will line up perfectly.
2. not too hard. Feed from the bottom up.
3. I highly doubt they will line up perfectly.
OK,
1. Where do I find C4 specific headers, any suggestoins
2. OK
3. If they don't line up, is there enough room to custom bend and intermediate pipe to bring them into line? do I have to scrap the whole thing and start from new? The system was $1200 and is still new. I'd hate to scrap them. It was done by the previous owner.
I expect that I would need two high flow cats, any problem with O2 sensors?
On these motors is there and O2 sensor before and after the cat, or just before?
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
They'll line up pretty close because there's not much room under there for anything to go anywhere else. If the headers you buy don't come w/ connector pipes, any compentent muffler shop can make the connection for you. I have L98 headers on my Lt1 for now and they lined up well to my stock cat back. I made up connectors from pipe from another stock system I had lying around, belled them and installed collector flanges on them. Some of the aftermarket headers have slip fit collectors which is a better set up IMO due to the close confines under there and because they are less prone to leaks.
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
What about the cats, I know they are $500 but I'd like to keep them street legal. Is there enough room between the X pipe and the header for the cats?
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Large Impressive Member
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by jsup
What about the cats, I know they are $500 but I'd like to keep them street legal. Is there enough room between the X pipe and the header for the cats?
Drifting
Joined: May 2003
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From: Lakeport CA
There are a couple of brands of headers, Hooker, TPIS & others will chime in I'm sure. I have the TPIS, drivers can go from the top, passenger, bottom only. Get the car as high as possible. I go top pin on my jack stands & set the rear tires on these steel boxes I have from an old fashion set of drive on ramps. Car sits level that way. TPIS comes w/ a new Y pipe that does away w/ pre-cats. Fits right to the stock main cat. Depends on your smog requirements if you keep that or gut it or X-over etc. Starter can stay but you need to pull the K-brace on that side & then re-install BEFORE you get the header fully mounted. Otherwise one bolt is impossible to get to.
Have fun!
Have fun!
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
In searching for headers I cam across some performance cats that were 3" and $500 a pair. Didn't say that was the answer, just the first ones I saw. I'd probably go the NAPA route too. $65 per, why not?
Obviously, I'll eliminate the pre-cats,kinda pointless. I was thinking of going the two cat route after the headers. I havn't seen a resonator mentioned, are you referring to the X pipe?
What about O2 sensors? 1 or 2 per side?
Obviously, I'll eliminate the pre-cats,kinda pointless. I was thinking of going the two cat route after the headers. I havn't seen a resonator mentioned, are you referring to the X pipe?
What about O2 sensors? 1 or 2 per side?
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Originally Posted by Trog
There are a couple of brands of headers, Hooker, TPIS & others will chime in I'm sure. I have the TPIS, drivers can go from the top, passenger, bottom only. Get the car as high as possible. I go top pin on my jack stands & set the rear tires on these steel boxes I have from an old fashion set of drive on ramps. Car sits level that way. TPIS comes w/ a new Y pipe that does away w/ pre-cats. Fits right to the stock main cat. Depends on your smog requirements if you keep that or gut it or X-over etc. Starter can stay but you need to pull the K-brace on that side & then re-install BEFORE you get the header fully mounted. Otherwise one bolt is impossible to get to.
Have fun!
Have fun!
Racer
Joined: Sep 2002
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From: Alma AR
No, They're long tube. You'll probably need heated O2 sensors. There is also a question of what size primaries you want. The TPIS and Hooker's are 1 5/8". !. 3/4" are supoposed to be better, and Headman and Stainless Works (I think) make those. The best bargen is the TPIS since you don't need to buy the front Y pipe. It comes with the kit.
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by jsup
In searching for headers I cam across some performance cats that were 3" and $500 a pair. Didn't say that was the answer, just the first ones I saw. I'd probably go the NAPA route too. $65 per, why not?
Obviously, I'll eliminate the pre-cats,kinda pointless. I was thinking of going the two cat route after the headers. I havn't seen a resonator mentioned, are you referring to the X pipe?
What about O2 sensors? 1 or 2 per side?
Obviously, I'll eliminate the pre-cats,kinda pointless. I was thinking of going the two cat route after the headers. I havn't seen a resonator mentioned, are you referring to the X pipe?
What about O2 sensors? 1 or 2 per side?
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From: Athens AL
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L98s do not have resonators. You have two small precats on the front Y that feed into the Main cat, it is NOT a resonator, although its nearly as big as one. There is no X-pipe on the stock system.
I would get the Hooker 2149, ceramic coated, or TPiS likewise coated. You do not require a heated O2 sensor, though it will not hurt you if you decide to get one, only rarely do people have the need to actually switch to heated sensors. I would replace the O2 in any event, if its never been touched.
The longtube headers will force you to delete the two small precats, but they will bolt up to the main cat in approx. the stock location. It can require some banging with a mallet to fit perfectly though, and there shouldnt be any welding required anywhere if you buy parts for your year.
I would get the Random Tech or Car-sound main cat, they should fit with no problems and bolt to both the PE and the headers.
There is only 1 O2 sensor, on the drivers side just below where the exhaust manifold bolts to the front Y.
I would get the Hooker 2149, ceramic coated, or TPiS likewise coated. You do not require a heated O2 sensor, though it will not hurt you if you decide to get one, only rarely do people have the need to actually switch to heated sensors. I would replace the O2 in any event, if its never been touched.
The longtube headers will force you to delete the two small precats, but they will bolt up to the main cat in approx. the stock location. It can require some banging with a mallet to fit perfectly though, and there shouldnt be any welding required anywhere if you buy parts for your year.
I would get the Random Tech or Car-sound main cat, they should fit with no problems and bolt to both the PE and the headers.
There is only 1 O2 sensor, on the drivers side just below where the exhaust manifold bolts to the front Y.
Melting Slicks
Joined: May 2004
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From: Lufkin Texas
St. Jude Donor '05-'06
Not trying to hijack thread but where's the best place to get the TPIS headers? I thought I was going to get hookers but that fell through. Are the TPIS coated or is that extra.
TIA,
Dave
TIA,
Dave
Drifting
Joined: Aug 2004
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From: Oceansaide CA
Originally Posted by vader86
\
There is only 1 O2 sensor, on the drivers side just below where the exhaust manifold bolts to the front Y.
There is only 1 O2 sensor, on the drivers side just below where the exhaust manifold bolts to the front Y.
I was actually about to make a thread, called "Can't find my other oxygen sensor!"
So how come the L98 only has one? That's so weird!
Safety Car
Joined: Apr 2004
Posts: 4,532
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From: Lahaina Hi
The computer is not smart enough on an L98 and only one wire.
The lt1 has 3 and 4 wires the SFI needs it to mang the engine,the L98 just needs an 02 to tell the computer the pyro temp is right so it can richen and lean the engine.
The L98 has 9 injectors.
The lt1 has 3 and 4 wires the SFI needs it to mang the engine,the L98 just needs an 02 to tell the computer the pyro temp is right so it can richen and lean the engine.
The L98 has 9 injectors.
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
So if I'm reading correctly TPIS or Headman 1.75 tubes will bolt right up.
After the header, I can bolt on the 3" performance cats, without much modification, just a little banging.
And finally, that should land me in just the right spot for my current cat back.
The Driver's side is a top down thing and the passenger side is bottom up. The frame needs to be unbolted to get the passenger side in correctly.
There is only ONE O2 sensor in the whole car? Headers looked at seem to have provisions for O2 sensors already there.
Even thouth the car has less than 30K, I'll replace the O2 sensor, easy enough.
Do I understand it right?
After the header, I can bolt on the 3" performance cats, without much modification, just a little banging.
And finally, that should land me in just the right spot for my current cat back.
The Driver's side is a top down thing and the passenger side is bottom up. The frame needs to be unbolted to get the passenger side in correctly.
There is only ONE O2 sensor in the whole car? Headers looked at seem to have provisions for O2 sensors already there.
Even thouth the car has less than 30K, I'll replace the O2 sensor, easy enough.
Do I understand it right?
Safety Car
Joined: Jun 2000
Posts: 4,870
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From: Long Island, NY
My recommendation is the Hooker Supercomps 2149's.
They have all the O2 sensor and emissions hookups.
And, they will give a huge HP gain over the stock system.
Forum member, TA, just put them on and ask him how he likes them.
Vic
They have all the O2 sensor and emissions hookups.
And, they will give a huge HP gain over the stock system.
Forum member, TA, just put them on and ask him how he likes them.
Vic