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Discussion Starter · #1 ·
on my 72 scout, I can either notch the firewall and run the exhaust down beside the trans, or bend a flange out of the way a little and run it over the top of the trans and back. if I wrap it with header wrap, do you think the trans tunnel will still get real hot? my buddy thinks it will heat the inside of the scout too much. I just figured i'd wrap it and then put some aluminum sheild spaced 1/2 away from the body sheetmetal to help dissipate the heat.
 

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Your plan sounds great! You could even double-layer the wrap.

The shield with the air gap will help a lot.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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On my Scout I cut and made a tunnel for the down pipe on the passenger side. Routed the exhaust down behind the bell housing and under the trans. The pipe was wrapped with high temp tape to prevent heat transfer. The pipe then follows the factory routeing alone the drivers side. A real PIA. Had I thought about it before buying a right drop transfer case, I would have changed over to a left drop axle and transfercase and life would have been a lot better.
 

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Discussion Starter · #4 ·
yea i've looked at your pics, and was gonna do it that way, but then I saw I had enough room to run it over the top, which will keep it out of the rocks, and not interfere with my smooth belly skidpan I wanna build. anyone else?
 

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hope this thread ain't dead

I was just getting ready to post this exact same thread and saw yours. I've mounted my 4b, trans and t-case and am ready to drop the body back on the jeep (CJ-7). I left as much clearance as possible between the turbo and firewall. However, if I drop on the passenger side, I have a passenger drop T-case and would have to cross over. No room for that under the tranny... don't want to do a stack out of the hood.. and am wanting to cross behind the head of the block.

Is that what you ended up doing on your scout? If so, how's it working and if not, why?

Am I missing an option? Also, if I wrap it (which I would), don't you have to change the wrapping every few years? That stack is starting to look pretty damn tempting!
 

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From where the flange face meets the turbo to the back of the 90* I made here is 4.75", much tighter than the breadtruck exh, making something like it could help.



 

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Yeah, that would be perfect if I had something to do with my exhaust once it was turned down. Do you think that 4.75 would be tight enough if rotated to go behind the head and above the flywheel housing?

Hubjeep, how's the clearance on the front of your engine? I'm running the CJ/wrangler flex-a-lite duel fans and will be trying to cram the break truck's massive inter cooler in front of the radiator. I'm anticipating some fab work on the grill, but it already looks like it could get somewhat tight if I'm not careful.

Also, by eyeballing it, it looks like I could run into steering shaft issues between the column and the box. Any pics of yours? Tight but still fits?!??? (i hope) You're my new 'go-to' guy on this... so get cozy! :smokin:
 

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Routing over the trans to the drivers side is what I and another landcruiser guy have done. I have plans to wrap my downpipe but have yet to do. It does get hot if it is not wrapped. Don't have a pic and i am off on vacation for a week but i'll see if i can post when i get back.
 

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I too am running the downpipe over the tranny so I don't run into my driveshafts. I took a long hot trip without my downpipe wrapped and it was hot. I'm not running carpet but have coated the inside and underside of the firewall/cab with heat stuff and on a hard pull the floor by the downpipe was too hot to touch. I then wrapped it and while it gets warm, it made a big difference. If you wrap, heat shield, and are running carpet inside you won't notice anymore than what the gasser put out.

raw wrap



painted with recommended hi temp coating



This is pre wrap. The scuffs on the firewall are from taking it out and putting it back in a bunch of times. Firewall is coated with spectrum firewall.



 

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I then wrapped it and while it gets warm, it made a big difference. If you wrap, heat shield, and are running carpet inside you won't notice anymore than what the gasser put out.
How many times did you wrap it (layers)? A buddy at Napa says that they sell a wrap he uses for about a dollar a foot. Hi-temp coating specific for heat reduction or just heat resistant to protect the wrap? I'm not running carpet (yet) but the inside and underside of my tub are both rhinolined... including the lower part of the firewall.

So far I'm gathering that I should:
Wrap, coat the wrap, run some sort of a heat shield on the firewall and maybe even think about carpet (which would help with noise and heat).

I just want to start driving the damn thing!!!:)
 

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Just one layer and I generally overlapped by 1/4-1/2" inch. I bought a 50' roll and have about half left over. This is what I found at the first place I searched so I bought it instead of deal hunting.



If you want to drive it then go for it. Then you'll know what you want to focus on first. ;)
 

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I use 5/8", Zero clearance, high density, Ceramic Blanket with heavy foil face. Its rated to 1800 degrees. Its available in Furnace Supply houses and approved in NY State for zero clearance. You can hold you hand on the foil side of a hot exhaust pipe and she is barely warm. Its not cheap, but it sure works.

Paul
 

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Discussion Starter · #13 ·
I used that same wrap and it seems to work great. took it out wheeling for a day and never got hot inside, but I didn't drive it there, we trailered it. I will leave it alone for now as it works.
 

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Just one layer and I generally overlapped by 1/4-1/2" inch.
I always overlap more than half the width.....the stuff works best that way, since you effectively have two layers at all times. So, if you use 1" wide roll, overlap 1/2" or more, and 2" wide roll overlap 1" or more.

For coating the tape, I used the high-temp spray paint (white) on my Ranger 5.0 and that engine gets way higher EGT than a diesel will. No problems after 7 years.
 

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a well-thought out heat shield will do wonders, its hard to believe. Guess that's why so many OEMs use them....
 
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