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This may be a stupid question - but I like asking stupid questions .... :D Is there an aftermarket replacement for the std exhaust manifild ? I understand they are cast and restrictive - But for those of us who spend $$ on hi-flow turbos - can we get a better manifold, then ceramic coat it ??

Cheers :)

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What do you think I have just had made? I've got a tubular manifold made, flows much better, and is getting ceramic coated. Most tubular manifolds are made from either stainless steel or mild steel, but many stainless ones are prone to cracking. Cost about $1000 for a decent tuned length replacement.

I have gone for a larger turbo, hence the need to replace the manifold. The cast manifold is very squashed in it's design, and making a tubular manifold in exactly the same position would be pointless, but you can certainly have a tubular manifold made for the stock turbo and keep it low-mount, would just mean some minor alterations to both the dump and intercooler pipes.

I took the exhaust manifolds off the car on my old vehicle and wrapped them and got them back on in about 2 hours. The wrap stayed on there for 12 months before I sold the vehicle and I didn't have any dramas at all.

I've also helped someone wrap his exhaust on the car, depending on the vehicle it is possible, but not the easiest thing to do.

Dont the GT30 series have the same flange as the stock turbo's on the RB25DET? if so you could get a tuned length manifold made to use with standard turbo, til GT30 upgrade is made!

does this sound valid? should improve response from the standard turbo too right?

I dropped it at my local exhaust specialist on the way home yesterday (where I got my front/dump/cat done).

He suggested that if I wanted to turn my car into a race car that wasn't a daily driver and if I had plenty of money to burn then sure go for it. But if its a daily driver with light trackwork then all its going to do is shorten the life of the front/dump pipe down to about 8-18mths.

He's had many cases where the dump pipes only lasted from 8mths (RX3) through to only 18mths (R33) because the pipes could expand and contract properly with the heat.

benm... could you clarify your above post... i dont really understand the reason why it shortens the life of the exhaust.

As for a tubular manifold for the stock/hi-flow turbo, i think you would have a pretty good chance at making one to sit the turbo in its factory location using original water/oil/dump.

B-Man are you interested in trying to get one for your car?

Originally posted by Roy

could you clarify your above post... i dont really understand the reason why it shortens the life of the exhaust.

Sorry I can't because I didnt understand it really myself. I spoke with 1 of the mechanics at 'Cobra Exhausts' in Penrith on Mulgoa Rd just next to Westbus. Don't have the number on me but im sure its in the phone book if your keen.

B-Man are you interested in trying to get one for your car?

Tubular manifold for std/hiflowed turbo - YES definitely. When I ripped my turbo off the other day, the std exhaust manifold looked pretty ordinary - I reckon that there has to be more power/effeciency in a tubular manifold.

The problem is connecting the cooler, dump, wastegate pipes up as well - but saying that they are all in fairly standards positions.. ? (As GTS-t VSPEC pointed out)

Roy, do you know who does these ? They prolly are expensive hey ?

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