Can't get OEM twin scroll manifold to line up, bent?
 

Almost a year ago I bought an used twin scroll exhaust manifold from a member and got it shipped to me in Sweden.

Now when I'm doing my build I noticed that the up pipe is impossible to line up with the turbo bracket. The up pipe doesn't come up high enough and it's too much forward too so it actually touches the bracket. I also had to force the manifold onto the head studs so already there it was obvious it wasn't a perfect fit.

I have tried probably all ways of tightening the manifold/up pipe, only thing that works is first tightening the turbo to the bracket and the up pipe to the turbo. That gives a gap of about 8mm between the up pipe and manifold that I have to force together by tightening the bolts. Can't be good, feels like it will crack that way. It would also be a nightmare to replace the turbo if needed.

So what do you think? Has it been damaged during shipping? Can't see anything obvious but maybe it's hidden under the heat shields. I really can't think of what the problem could be otherwise? The turbo bracket is brand new and I find it unlikely to be the problem (the manifold didn't fit great on the heads either as I said).

https://cimg7.ibsrv.net/gimg/www.sco...d37ce970ac.jpg

Hi I think the sump needs changing aswell when putting equal length twinscroll manifold on as its DIFFRENT to the sump on the unequal length manifold :thumb:

Yea usually need this !!

http://www.importcarparts.co.uk/part...ll&searchPart=

Thanks but I already have the twin scroll sump. I wouldn't have been able to bolt the manifold to the heads with the old one :)

You didn't mention the sump and you was having problems putting the manifold on, what about the spacer kit that's available on eBay maybe that could help?

The problem was that the holes on the manifold's exhaust flanges didn't line up perfectly with the studs on the heads. The holes were slightly off meaning I would have to stretch out the halves of the manifold just to get it down on the heads, as if it's not wide enough to fit on the engine.

I'm more and more convinced it must have been hit during shipping. Perhaps the flex section under the heat shield has been crushed. That or a repair where it's been welded up somewhere under the shields.

Will look into the spacer kit but I'd rather prefer to try another manifold I think. I can't think of anything else being wrong unless my engine is crooked :D

Sounds like it could be bent,are you sure it's not just the heat shields that are fouling?
I have the twin scroll set up on my classic,has the oem manifold and up-pipe.
No shields on mine tho as I've wrapped them,they are a perfect fit tho and all line up very well.

No it's not the heat shields as far as I can see.

I've been trying to look at pics of JDM STI's twin scroll engines and I really can't see anything obviously wrong. Neither is there any obvious damage or dents anywhere on the heat shields or piping. It seems that if I would put an extra flange as a spacer between the up pipe and manifold it would fit decently.

https://www.jspecauto.com/images/Eng...3_DSCN4893.jpg


https://cimg4.ibsrv.net/gimg/www.sco...2a8f96a0af.jpg

The difference in height

https://cimg7.ibsrv.net/gimg/www.sco...dfd5870f1b.jpg

Don't know much about the differences but there was a thread a while back about the legacy and impreza twin scrolls being a different fitment. Try and find it.

I was gonna suggest that, seeing as earlier you said there was a constant gap. Not ideal, maybe...but needs must, and all that. :|

I read about the Legacy manifold and it seems that the flanges have a completely different shape between the manifold and up pipe but also at the turbo so I'm sure it's the right manifold.

Removed the shields today but all looked fine so put them back on. How much of a gap is acceptable to force together by tightening the bolts? Put everything back on and had about 6 mm. I think I will leave it bolted together like this for a while and see if it reshapes a little bit.

Odd problem, I think I will try another turbo bracket as it must take quite a bit of force to bend the manifold or up pipe out of shape.

Just got a reply from the member who sold it to me:

"When he fitted them on his engine stand the new bracket made fitting a little more difficult than usual. He fitted everything loose including the bracket and then tightened all the pieces together. He thought it a little odd but when tightened sequentially everything was fine. He never thought to mention it to me as it never troubled him throughout the time it was driven afterwards. Hope this helps you."


I guess it will work just fine but I'm a bit too picky for my own good so I'll see if I can find another manifold cheap to compare with ;)