Both the cars I have recently purchases have cracked exhaust manifolds which have worsened. UK blob wrx 03 and 2 litre JDM twin scroll GTB. I am happy to replace with stainless steel if that is best option. Can anyone advise on part numbers or best after market replacements? Ta!

 

Cracked or leaking gaskets??? The bottom joint on the up pipe is also a favourite to go.
UK "manifold"

 

Thanks for info. Impreza sounded like a tractor and is cracked. I'll check with mechanic where tomorrow. Legacy, I started to notice a tick and oils is leaking but yet to be looked at properly.

 

why would oil leak out of an exhaust??

the original Impreza manifolds are cast iron so unlikely to crack although up-pipes and the central x-over pipe can crack on the flexi joints??

 

Manifolds are like £30 from a breakers.

 

I don't think the car has original headers. I don't have a receipt, but a note of upgrades saying upgraded unequal length headers. Car has been running well with Td0520g and front mount etc. Sounds like a tractor at the moment.

Looking on ebay there are manifold kits with uppipe and gasketsfor around £300. Hayward and Scott twice the price which you would expect. Hadn't thought of one from breakers. Am I really going to notice much difference?

 

I think the crack is on flexi joint on both cars.

 

Not if they are still unequal. Buy some OEM ones and have them ported and wrapped

 

Must be cheap manifolds, I have a Japspeed one, been fine for years. As said of you don't want to pay crazy money do a said above standard and Polish and port.

 

factory cast manifolds with a suitable (e.g. "trick") up-pipe will be far better in general than s/steel aftermarket ones at sub 400bhp

even better if ported / flowed correctly