Jump to content
SAU Community

Recommended Posts

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 :)

  • Replies 55
  • Created
  • Last Reply

Top Posters In This Topic

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 ?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Yup. You can get creative and make a sort of "bracket" with cable ties. Put 2 around the sender with a third passing underneath them strapped down against the sender. Then that third one is able to be passed through some hole at right angles to the orientation of the sender. Or some variation on the theme. Yes.... ummm, with caveats? I mean, the sender is BSP and you would likely have AN stuff on the hose, so yes, there would be the adapter you mention. But the block end will either be 1/8 NPT if that thread is still OK in there, or you can drill and tap it out to 1/4 BSP or NPT and use appropriate adapter there. As it stands, your mention of 1/8 BSPT male seems... wrong for the 1/8 NPT female it has to go into. The hose will be better, because even with the bush, the mass of the sender will be "hanging" off a hard threaded connection and will add some stress/strain to that. It might fail in the future. The hose eliminates almost all such risk - but adds in several more threaded connections to leak from! It really should be tapered, but it looks very long in that photo with no taper visible. If you have it in hand you should be able to see if it tapered or not. There technically is no possibility of a mechanical seal with a parallel male in a parallel female, so it is hard to believe that it is parallel male, but weirder things have happened. Maybe it's meant to seat on some surface when screwed in on the original installation? Anyway, at that thread size, parallel in parallel, with tape and goop, will seal just fine.
    • How do you propose I cable tie this: To something securely? Is it really just a case of finding a couple of holes and ziptying it there so it never goes flying or starts dangling around, more or less? Then run a 1/8 BSP Female to [hose adapter of choice?/AN?] and then the opposing fitting at the bush-into-oil-block end? being the hose-into-realistically likely a 1/8 BSPT male) Is this going to provide any real benefit over using a stainless/steel 1/4 to 1/8 BSPT reducing bush? I am making the assumption the OEM sender is BSPT not BSPP/BSP
    • I fashioned a ramp out of a couple of pieces of 140x35 lumber, to get the bumper up slightly, and then one of these is what I use
    • I wouldn't worry about dissimilar metal corrosion, should you just buy/make a steel replacement. There will be thread tape and sealant compound between the metals. The few little spots where they touch each other will be deep inside the joint, unable to get wet. And the alloy block is much much larger than a small steel fitting, so there is plenty of "sacrificial" capacity there. Any bush you put in there will be dissimilar anyway. Either steel or brass. Maybe stainless. All of them are different to the other parts in the chain. But what I said above still applies.
    • You are all good then, I didn't realise the port was in a part you can (have!) remove. Just pull the broken part out, clean it and the threads should be fine. Yes, the whole point about remote mounting is it takes almost all of the vibration out via the flexible hose. You just need a convenient chassis point and a cable tie or 3.
×
×
  • Create New...