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TR4/4A No Clearance for Exhaust Manifold Header Pipe

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KVH

KVH

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There is literally no clearance between the exhaust header pipe coming off my exhaust manifold and the lip of my oil pan.

The pipe sits so tight against the oil pan that there’s even visible abrasion on the pipe, which is, of course, cast-iron.

I’ve been unable to make any adjustment, and I’m wondering how typical this situation might be.

I could “ double up“ on the exhaust manifold gaskets and move the entire manifold and carburetors perhaps another 16th of an inch distant, but I’m not sure that’s much of a fix.

Has anyone else experienced this clearance issue?
 
It seems unusual that any pipe in the exhaust other than the header itself would be cast iron. Are you sure? If not cast iron, its shape can be can be changed.
Bob
 
It is the header. The head pipe right below the exhaust manifold. It’s the header pipe rubbing on the oil pan lip.

The prior owner actually used some kind of adapter and welded the front resonator (muffler) directly to the down-curving header pipe.

My concern is is that somehow the welding distorted the header pipe.

I’m going to look again, but if I’m going to fix this, I may have to simply cut this entire unorthodox system out of my car and have something closer to stock reinstalled.

(FYI, my car has only a front resonator, and no rear mufflers. I’m not sure I’ve ever seen such an arrangement. Further, as I’ve stated, all connections are welded. There is nothing for me to take apart after the header is disconnected at the manifold. Welding gone wild)
 
Here are some pics. In the second two, can see the header pipe welded directly to the resonator. I think that’s the original header and it seems to be cast iron. Could it be an after market replacement, is there an easy way to tell?

The first pic is the back end of the resonator, just so you can see it welded there, too. I have no other mufflers. Just this forward one, which I believe is clearly an add-on of some sort. Called a Blue Bottle?
 

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I’ve seen a recent TR3 with just the resonator. Sounds a touch louder and a bit more raw/throaty. People do that for a peppier/racier sound and maybe an extra hp!
 
RichB4493 said:
I’ve seen a recent TR3 with just the resonator. Sounds a touch louder and a bit more raw/throaty. People do that for a peppier/racier sound and maybe an extra hp!
Click to expand...
Yes I think that is what someone did. It’s so “throaty” that I “putt-putt” through my neighborhood to avoid complaints from the usual cast of characters.
 
Quite the modification. A good muffler shop could fix that for you ( cut and reshape ) maybe adapt a muffler at the same time….without taking the manifolds off.
Fern
 
I've attached two photos that might be of some help. First is my cast iron split manifold that are found on TR4A's. The second photo is of the exhaust pipes and mufflers used on early TR4A's (including the dual downpipe that attaches to the exhaust manifold).

TR4A Exhaust Manifold.jpg


TR4A Exhaust System.jpg
 
Yes that looks perfect. It also appears from the Moss catalogue, if the same, to bolt up with standard pipe clamps. My current setup has chrome tips on each tailpipe at the rear bumper, tack welded in place, so I’d try to save or replace those. Thanks.
 
KVH said:
Yes that looks perfect. It also appears from the Moss catalogue, if the same, to bolt up with standard pipe clamps. My current setup has chrome tips on each tailpipe at the rear bumper, tack welded in place, so I’d try to save or replace those. Thanks.
Click to expand...
Okay...Since it is the 4A's manifold you're using, if you change to the original downtubes, you'll have that needed clearance to the sump (see attached photo)....and I use chrome tips too. They've got a slight downturn which keeps the bumper clean of soot.

TR4A Exhaust.jpg


TR4A pipes.jpg
 
KVH said:
Looks great. Are your chrome tips tack welded?
Click to expand...
Hey thanks. No they're not tack welded. Found some old 1 5/8" inside diameter chrome tips that were about 8" long with set screws. Cut them down to little less than 4" long. With the slight downturn, I just pushed them on the pipes till they hit the bend. Good tight fit with no movement.
 
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