Novak Conversions Jeep Wrangler TJ engine mounts

Flowmaster Pre-Cats (oil pan clearance advice)

MikeE024

MikeE024

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I'm looking for some help from someone with the Flowmaster Pre-Cats installed.

I had to cut my exhaust right after the point where the pre-cats joint, so I don't know how close the pre-cats would sit to the oil pan when all buttoned up with the rest of the stock-style plumbing.

I need the flanges to line up for a good seal, the exhaust to clear the DS yoke, and the exhaust to line up with the turbo's piping.

A measurement or photo would be helpful to ensure I don't put the exhaust too close to the driveshaft where the yoke will smash it in.

Here is what I'm looking at...


Further from pan (closer to the yoke)

Screen Shot 2024-09-21 at 6.49.22 PM.png


Closer to Pan

Screen Shot 2024-09-21 at 6.49.47 PM.png



Photo of the cut plumbing

Screen Shot 2024-09-21 at 6.50.04 PM.png


Thanks for any help that you can provide.
 
Good luck with that. I have Flowmaster cats and no matter how close I got them to the oil pan the drive shaft yoke still struck them. It just “re-formed” the pipes (both of them) slightly. On the other side, the upper Curry control arm also hit the pipe going to the Banks turbo inlet also re-forming that slightly.
 
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TurboTJ said:
Good luck with that. I have Flowmaster cats and no matter how close I got them to the oil pan the drive shaft yoke still struck them. It just “re-formed” the pipes (both of them) slightly. On the other side, the upper Curry control arm also hit the pipe going to the Banks turbo inlet also re-forming that slightly.
Click to expand...

That actually makes me feel way better.

I thought I had mine fitted properly last time, but the yoke dented it in a good amount. I assumed I messed it something up, but I can only adjust things so much or the flanges won’t seal.

It didn’t help that the PO of the kit mangled the plumbing at the elbow.

How close is your up-pipe to the oil pan? @TurboTJ It would be super helpful if I could see your up-pipe as a reference to ensure I’m good there. Would it be possible to send over a pic or two?

I’m being a little apprehensive this time because I want to get it right so I can be good for a while.

I installed a new exhaust manifold, so this will complete the job.
 
My up pipe is stock Banks. That won’t work with a skid plate that has a right side strut to the chassis. So my installation looks a whole lot different from yours. I’ll try to take a picture of it tomorrow. In addition to the up pipe, make sure your control arm does not hit the turbo oil return port on the sump. Happened to me. I laid down an oil slick and smoke screen for the record books.

BTW, I’ve got about 8 years on the Banks system now. Yeah, there were some fit problems but with everything sorted out now (more or less) it has performed flawlessly.
 
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TurboTJ said:
My up pipe is stock Banks.
Click to expand...

Mine too.
TurboTJ said:
That won’t work with a skid plate that has a right side strut to the chassis.
Click to expand...

I have a Savvy skid. I bought angle iron and the heated and bent it so it would work with the up pipe in that corner.

TurboTJ said:
I’ll try to take a picture of it tomorrow. In addition to the up pipe, make sure your control arm does not hit the turbo oil return port on the sump. Happened to me.
Click to expand...
Thanks man I appreciate it.

And thanks for the heads up. I don’t believe my oil return been an issue…it’s a short run from the turbo to the oil pan. I have about 9 inches of clearance so I should be good.

IMG_4855.jpeg
 
I thought I had clearance too. But I didn’t. This was before I added any bumpstop spacers. Now I have about 3/4 inch spacers. I only have a 2 inch lift.
 
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TurboTJ said:
I thought I had clearance too. But I didn’t. This was before I added any bumpstop spacers. Now I have about 3/4 inch spacers. I only have a 2 inch lift.
Click to expand...

IIRC, Blaine's outboarding work with the Fox 2.0 sets my up-travel to around 5-3/8", so the bumps should be set to that limit.

I've been hard enough on the rig that I probablywould have broken that by now if it was in question (especially when scooting around in the whoops last month). Coming off the trail, my camber was -2.8*, PSC steering gear was damaged, and my locking hubs were ruined...eeek.
 
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Zorba said:
Are these Flowmaster problems peculiar to modified Jeeps, or are they an issue with stock as well?
Click to expand...

This wasn't meant to be a problem thread, but it's a fair question that I don't know the answer to.

I didn't notice my pipe dented in until more recently, but I also can't say when it happened. Someone who knows his stuff said that this was a known issue with XJs, so he wasn't surprised to see mine dented in by the yoke.
 
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Don’t know if these are of value or not because our setup is different. Oem precats. Dims are marked at the tightest punch points as a reference so I can see if anything has moved. Seals solid with clearance.

IMG_7557.jpeg


IMG_7558.jpeg


IMG_7560.jpeg
 
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Zorba said:
Are these Flowmaster problems peculiar to modified Jeeps, or are they an issue with stock as well?
Click to expand...

I first saw the problem before I had the Turbo. I had just replaced the OEM cats with the Flowmaster. The later installation of the Turbo didn’t make it any worse. I have a 2 inch lift and have left the factory track bar in place. This positions the front axle about half an inch to the left side which of course results in more clearance to the drive shaft yoke. It still hits though.
 
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