Exhaust Manifold Adaptor Flanges

[silman]

I've just purchased a cast for my RB25DET in a 180SX setup. (not on the road yet)

The manifold is designed for IHI/Apexi Turbo's and a Greddy Type R External style wastegate.

I have a GCG Garrett GT30/40R (.63AR) Turbo, and a Tial 38/40 External Wastegate though, and need some assistance with adaptor flanges.

Can anyone advise where i could buy such adaptors?

Is it likely that i'll have to buy a 38mm tial adaptor, and a (??mm) Greddy Type R Adaptor and have them welded together to make it join up?

Thanks.

Edited November 4, 2007 by silman

[BHDave]

In a nut shell yes. Though you can get your exhaust shop to make up custom flanges for you to if your in a bind and cant find any off the shelf

As the manifold is cast it isn't as easy as lopping off the flange and welding on a new one.

It does look like the wastegate flange already has an adapter on it as well which you should probably remove to tidy the whole thing up a bit.

Where you will benefit though is by having the adapter you can cutsom make it to fit the wastegate pretty much where ever you want to mount it.

And atleast you know the manifold won't crack.

[Craved]

most tials come with flanges when you get them, an exhaust shop can get a laser cut flange done custom pretty easy (for the manifold end of the wastegate feed - had to do that for exhaust flange on my turbo) then weld up a pipe to position the wastegate lower in the engine bay.. to keep some of the heat away from other gear

prob quicker and easier to just get them to do the mod on the turbo feed too.

[paulr33]

i would have thought a genunie apexi one would have been better designed than that

[silman]

i would have thought a genunie apexi one would have been better designed than that

Are you really in the moderators group?

what's so wrong about this manifold?

keep in mind the flange sits back to keep the centre of gravity towards the middle of the car. The wastegate points straight down to avoid heat issues. What exactly is so bad about it?

[paulr33]

yeah i am in the moderators group, how come?

nah sorry i should have re-said what i meant

i expected tuned lenght tubular style instead of log style

no real reason why, i just expected that i guess

[silman]

to brutally honest, your first reply was not helpfull, and didn't answer any of the questions i asked and either has your second. I'd expect more from a moderator.

thanks to the rest who replied, i'm going to look at selling the tial and purchasing an hks w'gate.

As for the turbo, i rang gcg today to ask if they have any experience with using an apexi/ihi turbine housing on any of there gt range turbo's to which the answer was no. Will have a custom flange built up to retain the current turbine housing i have.

[paulr33]

right and so because im a moderator im expected to instantly answer everyone's questions?

i dont think thats the case at all. its an open discussion forum for exactly that, an open discussion. i never said the product was good or bad, i just commented on it. sure it didnt help. it's not like this place is an online helpdesk system, its an online discussion board.

sorry if you were given the wrong impression.

[Craved]

just noticed that this manifold would fit both RB26 and RB25 ..

wouldn't see it as being as efficient as a tube style, and the wastegate feed is in an opposite direction to the gas flow..

but still would beat any modified std log manifold with external gate flange welded on.

interested to see how much room you have for the dump pipe too, with the turbo sitting so far back, will be tight to the firewall in a sylvia/180 i would think.

check your prices for HKS wg's too, very pricey, might be cheaper to get the flange made than swap to HKS unit. dont go the cheap copy, they suck balls

[silman]

Yep, also fits RB20. I agree it wouldn't be as efficient, but i weighed that up against not having to worry about a cracking manifold. The dump pipe will be a very tight fit indeed. I buy everything from Greenline. Yes definitely wouldn't risk my setup on a cheapy hks copy.

[Craved]

my std cast manifold cracked, so it can still happen but less likely.

good luck with the conversion!

[BHDave]

I didn't comment on the turbo inlet flange before, but it looks to be common t3 sized so you shouldn't have an issue.

You can always wander into gcg or garrett with the manifold and ask to trial fit a t3 flanged turbo.

check the centre to centre spacing of the studs, T3 is 86mm/43.5mm (long/short side), T2 is 73/38.5.