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The end all Exhaust/ Header thread!

Renix. Not bored

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OK, I can see if I still have a RENIX TB and bore it out straight, if you want to try it. Also, the RENIX has a bit lower exhaust ports and I think the cam is a bit milder. Not much. So, it might puke out a bit sooner than an HO. Still, I feel a bit of a taper off of power on my 2000 about 4000-4500 RPM.
I'd try it. How much do you want for it?

4500😳 mine never runs over 3000

I bought a ho gasket and soon realized I couldn't use it because renix ports are substantially lower.

I didn't measure but I think the ho ports at the head are smaller.

I also think the ho horse has less volume all around as ports are streamlined in a horse shoe.
Is this because.

Wouldn't less air mean its slightly richer or is it actually more air volume in the ho intakes?

It looks like gasket matching exhaust intake and head could potentially wake things up as ports could have a fair amount of material removed. Well maybe bigger isn't always better.

Can you knurel the throttle body bore maybe just the bore below the plate.

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If I can find the RENIX TB, I'll bore out the restriction, so 58mm. Then I'll just send it to you. I did look last night. I wonder if I put it in the Silver XJ.
Head ports are funny things as I understand. Larger size is not always the best. Also, shape plays a part and depends on what RMP range you are to run. At least that is what I read.
Thank you but you don't have to though it would be cool to see what kind of change there is.

My muffler gets here tomorrow so hopefully its better than my no flow through technology muffler.

I might also start searching for a horse shoe and gather throttle cable, tps adapter and the other needed things I can't think of right now. Maybe winter project

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I haven't found my RENIX TB, yet. My 2000 did a bit better with the JBA exhaust header. Still, hard to tell. I did make it to the Carlise or PA Jeep All Breed Jeep Show. I picked up a used Pace Setter header. It was from a TJ. I'll have to adapter the down pipe or buy one. Overall it looks OK. Its a Tri-Y design. The primaries are dia 1.5, so 1.375 ID. The secondary's are 1.970 OD. The collectors are about 2 inch ID. So, a bit small. It will go on a '98 I am going to sell.

Edit: I looked further at the Pace Setter XJ vs TJ. The XJ has slip fit for the cross over or down pipe. Though two pipes, unlike the older style. The TJ has the ball socket type like the 2000+
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Don't sweat it i just lost my jeep in a flash flood.
Well kidding kinda.

Mine is running pretty well noticeable power improvement after adjusting tps not sure what the exhaust improvement or not. It sounds better. Pipes are already all beat up

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Following up on the big exhaust theory write-up I added to this thread a while back (https://www.naxja.org/forum/showpost.php?p=246730884&postcount=44)

I'm finally posting detail reviews of the AFE Twisted Steel header in my build thread here:


Happy so far... A couple teaser pics just because:




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Very nice I think most welds look good that are better than I can do, most look good good.
Did you run it it yet.
From your pictures I assumed the manifold you are replacing was stock

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