New Exhaust Manifolds

[swell610]

Dear Fellows

350SE with new manifolds fitted in 2000. Unfortunately the position of the exhaust pipes and the holes in the head ......do not correspond. Hence, the rather nasty tractor like sound and the inability for new gaskets to silence the aforementioned. The downpipe also rests on the chassis - giving a non soothing clunking sound at tick over!

The head was gas flowed by RT Racing many years ago - leaving less material to 'join' to - but I guess enough - for as long as the holes match up.

Do I (1) need to get someone to make new manifolds? if so can anyone recomend or (2) can I buy new / secondhand items off the shelf (and will they fit / adapt to my aftermarket ss exhaust system?)

Any help much appreciated.

[leorest]

Other than the sealing problems are you happy with the quality/look of the manifolds? If so then you might be able to get them modified to fit properly. This would be a lot cheaper than making from new.

[swell610]

Very happy with the look. Would just need somebody to do the fix - any ideas

[sphs2]

The manifolds are a very close fit to the chassis if everything is perfect, so for example are your engine and gearbox mounts ok? if these have half collapsed it may well cause the manifold to hit the chassis, which would then cause lining up problems.

[swell610]

I did ask the garage to check these - and they reckon they are fine. I think the telling thing is that some allign - and some do not.

[rev-erend]

Depends on the misalignment on the head - might be possible to file any bolt holes that are a very tight fit. These exhausts are always tight in places and have to be presuaded to fit .. read into this large 4 lbs hammers and big lever bars.

Good luck with it.

[swell610]

Thanks for that - I'm in the Cambridge area - do you know of any hammer weilding bar toting exhaust men about?

[rev-erend]

I would take each manifold and make sure that it's an easy fit on an old RV8 head - out of the car .. file any that are tight.

Then it will fit much easier when in the confines of the engine bay.

[TVRleigh_BBWR]

maybe a bit far to come. but if you want I can lend you a 350 Head.
be easier to see why it's not fitting.

[djc100]

Many Wedges do have a dent {via the hammer) in the down pipe as it passes the chassis.

David

[adam quantrill]

Guy - I live in Sawston - you could swing by and I could take a look.

Even if the engine mounts look OK you can get 1/2" extra clearance by loosening the bolts, jacking up the engine under the sump, and tightening again. Worth a try.

[Comadis]

you trust your garage? is there a prove that they really checked the engine mounts? often garages tend to say "everything ok" and type an invoice instead making their fingers dirty!!!

before i would use the "hammer-method", i would buy some new engine mounts, change them and see what happens. the parts arent expensive and even when they do not solve the actual problem they will give you some improvement anyhow!!

[swell610]

Thanks very much all you guys. ACT have been helpful and alerted JP exhausts who apparently make all the stainless manifolds. Sebring are going to take the manifolds off and send them to JP for checking. I guess JP will either sort the existing ones or send me a new pair. At the same time we will double check those engine mountings and very possibly put new ones in - can't be a bad thing and may help the downpipe snagging the chassis.

Thanks once again.

[GRIFFONMARK]

My 350i exhausts touched the chassis and I had no problems with the exhaust. However, I do agree that there is a slight amount of play in the bolt holes of the engine mounting blocks so I would definitely look at loosening them off, jacking the engine and then retightening. I don't know why the exhausts don't line up with the head though, there should be plenty of room. Most of the manifolds I've seen have holes much bigger than the ports. I have seen one set of manifolds with round holes which obviously were no good for rover heads. The other problem is if the gaskets are the small ones or fitted incorrectly. It's easy to fit them the wrong way round. Also, you need to be careful fitting the manifolds, I think the middle bolts need to be nipped up first otherwise you get problems lining everything up. It took me 2 or 3 goes last time I did it. Regards, Mark

[swell610]

Thanks guys for all your responses. Just to let you know what happened. ACT performance were very helpful indeed in organising (FOC) for JP exhausts (who apparently make all the ss manifolds) to check out my existing manifolds (again FOC). JP exhausts did this and found the manifolds to be piss poor. Luckily I have been able to source a new set and the car is back on song. Literally.

Big thanks to all you guys, ACT Performance and JP exhausts - and of course Matt @ Sebring who has to put up with me!