Longtubes
Thread Starter
Racer
Joined: Jan 2001
Posts: 322
Likes: 0
From: Liberty Township OH
Longtubes
I have a '96 LT4 & am trying to figure out what it would take to put on some longtube headers. I plan on getting 'collector plates', so, could I just eliminate the cats? I think I would need an x-pipe, but am not sure. Should I get headers with the smog fittings or not? Anyone have any idea what the entire conversion would cost me?
Racer
Joined: May 2001
Posts: 320
Likes: 0
From: TX
Re: Longtubes (Polar LT4)
You can run long tubes to a standard cat-back exhaust with some minor fabrication. If you do not run cats, you need O2 simulators which run about $100. Other than that all you need are the headers. I got my Hooker 2151s for $290 shipped from Summit. You need to add the O2 bungs to the headers. They cost $5 each from a muffler shop. Get the smog fittings if you think you need them. I can get away without having such stuff and it makes the install a lot easier.
The install is not terribly difficult but there are a couple pitfalls. The spark plug wire holders do not work in the rear because the holes are blocked. It takes a little fabricating to get them to work. The AC bracket does not line up perfectly, but we added a washer to act as a spacer and there are no problems.
The install is not terribly difficult but there are a couple pitfalls. The spark plug wire holders do not work in the rear because the holes are blocked. It takes a little fabricating to get them to work. The AC bracket does not line up perfectly, but we added a washer to act as a spacer and there are no problems.
Instructor
Joined: Sep 2001
Posts: 130
Likes: 0
Re: Longtubes (Polar LT4)
Here's another approach. I used TPIS headers. Fit was good. I only had to grind some off the bottom of the 2 rods that go to the AC bracket. Maybe 1/8" or so, easy work with a 4" grinder. I also shortened the bolts for the spark plug wire brackets. The headers are already drilled and tapped for this. I am reattaching the Air injection tubes, though it would be easy to leave them out and cap the header ports. Life is great if you can leave out the cats, I'm going to use bullit cats for visual inspection, and to quite the exhaust note down some. If you are going to do other mods to the engine, instead of O2 sims, I am going to turn off the second O2's using LT1Edit. For exhaust, I got an X-pipe from Spintech, but that has not gone into the car yet. From the looks of mine, you could modify the OEM exhaust to met up to the header collectors.
Jeff
Jeff
Thread Starter
Racer
Joined: Jan 2001
Posts: 322
Likes: 0
From: Liberty Township OH
Re: Longtubes (kkonen)
Can I use stock cats w/ the longtubes, or won't they fit? If possible I would rather ratain the cats, but if it's not possible I can lose them. BTW - when I get the collector plates (& will not have to do e-check) can I get in trouble for dropping the cats?
Burning Brakes
Joined: Aug 2000
Posts: 984
Likes: 1
From: Cincinnati OH
Re: Longtubes (Polar LT4)
Can I use stock cats w/ the longtubes, or won't they fit? If possible I would rather ratain the cats, but if it's not possible I can lose them.
BTW - when I get the collector plates (& will not have to do e-check) can I get in trouble for dropping the cats?
[note:] no opinion of whether it's right or wrong, just reporting the facts :blueangel:
[Modified by Vince Ivanc, 2:19 PM 6/7/2002]
