Exhaust question?
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Melting Slicks
Joined: Mar 2003
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From: Franklin IN
Exhaust question?
Does anyone know if I can use a early front "y" pipe like a 87 on a 93? Will the flanges fit the LTx manifolds? Is it wide enough to fit around the engine? Why do I want to do this? I want to get the catalytic convertors from the engine compartment. The heat is so high that the factory wrapped the engine mounts in heat reflective material. I think I would use a Cat but I would use a high flow cat further back like the earlier models or the Random Technology units. Looking for suggestions thanks!
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From: Lacey WA RVN 68-69
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The OEM cats do get the area hot, but the insulation is there to prevent things from getting so hot, they melt or dry up and crack.
The OEM 87 Y-pipe has pre-cats and that pipe connects to a "main" cat where your LTx exhaust has a resonator. If you look at the 93 exhaust pipes, you will see one has a flange for bolting to the resonator input and the other is a slip-fit. They are also not equal lengths.
The 87 Y-pipe uses slip fit connections and they are equal length. The 87 pipe is also smaller in diameter. IIRC it's 2 1/4" where the 93 pipes are 3". So the flanges are going to be different and they probably won't clear the starter on one side and the oil filter on the other. It's hard to say if there will even be clearance around the bellhousing based on the trans in the car.
You didn't say if you have to have the car smogged, but some states won't even let you relocate a cat, much less use a single cat where the OEM provided two cats. And a reputable shop won't remove working cats. It's a violation of federal law and the fine (if they get caught) can be in the 5-figure range.
The OEM 87 Y-pipe has pre-cats and that pipe connects to a "main" cat where your LTx exhaust has a resonator. If you look at the 93 exhaust pipes, you will see one has a flange for bolting to the resonator input and the other is a slip-fit. They are also not equal lengths.
The 87 Y-pipe uses slip fit connections and they are equal length. The 87 pipe is also smaller in diameter. IIRC it's 2 1/4" where the 93 pipes are 3". So the flanges are going to be different and they probably won't clear the starter on one side and the oil filter on the other. It's hard to say if there will even be clearance around the bellhousing based on the trans in the car.
You didn't say if you have to have the car smogged, but some states won't even let you relocate a cat, much less use a single cat where the OEM provided two cats. And a reputable shop won't remove working cats. It's a violation of federal law and the fine (if they get caught) can be in the 5-figure range.
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Your gonna lose HP with a Y pipe. I think its different enough to not mate up.
Since your gonna spend that kind of money how about long tube headers, bullet cats and dual exhaust with maybe an x pipe instead of the resonator?
Since your gonna spend that kind of money how about long tube headers, bullet cats and dual exhaust with maybe an x pipe instead of the resonator?
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Let me get this straight. You would like to remove the OEM cat system which has heat shields from the cats all the way to the end of the tranny. You are thinking about using a L98 tubing which is smaller or Random Technology cats which comes without heat shields.
The OEM cats with heat shields are the cooler set up out there. Trust me on this one, I installed hi-flow cats without heat shields and ended up wrapping them up with heat wrap and with the heat wrap they were not cooler than the OEM set up.
To each it's own.
The OEM cats with heat shields are the cooler set up out there. Trust me on this one, I installed hi-flow cats without heat shields and ended up wrapping them up with heat wrap and with the heat wrap they were not cooler than the OEM set up.
To each it's own.
Thread Starter
Melting Slicks
Joined: Mar 2003
Posts: 2,512
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From: Franklin IN
What I'd like to do is to eliminate the CATS but I can't find any test pipes. I don't have to have the car smogged so that is not a concern. I have considered LT headers but 1500.00 is to me is out of the park. And if I do I couldn't run the stock CATs anyway. I would prefer to run straight pipes to the resinator. I'm looikg to see what others have done.
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From: Lacey WA RVN 68-69
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There is no real reason to remove the OEM cats if you are not going to go with LT headers. The factory cats actually flow very well and keeping them on (smog testing or not) will help the air. The OEM exhaust size is 3" and that helps with exhaust flow. I don't think there are any "test pipes" available through the catalogs like there used to be years ago.
Radiant heat is not an issue as the engineers have handled that. Unless you have some of the heat shields missing, you should not have a problem with interior heat from the exhaust.
What you should consider is a cat-back system. Some systems will provide a HP/TQ gain and provide a nice exhaust note with very little cabin resonance or drone.
Radiant heat is not an issue as the engineers have handled that. Unless you have some of the heat shields missing, you should not have a problem with interior heat from the exhaust.
What you should consider is a cat-back system. Some systems will provide a HP/TQ gain and provide a nice exhaust note with very little cabin resonance or drone.
Thread Starter
Melting Slicks
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Let me get this straight. You would like to remove the OEM cat system which has heat shields from the cats all the way to the end of the tranny. You are thinking about using a L98 tubing which is smaller or Random Technology cats which comes without heat shields.
The OEM cats with heat shields are the cooler set up out there. Trust me on this one, I installed hi-flow cats without heat shields and ended up wrapping them up with heat wrap and with the heat wrap they were not cooler than the OEM set up.
To each it's own.
The OEM cats with heat shields are the cooler set up out there. Trust me on this one, I installed hi-flow cats without heat shields and ended up wrapping them up with heat wrap and with the heat wrap they were not cooler than the OEM set up.
To each it's own.
