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Was looking at exhuast manifolds and was looking at this hpi one at just jap priced for 1700 which says it keeps the exact stock postion. Now my question is is this a worthwhile to consider getting considering I got the usual mods turbo injectors ecu etc. 270kw , How much more benifet could I receive over the stock manifold?

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Was looking at exhuast manifolds and was looking at this hpi one at just jap priced for 1700 which says it keeps the exact stock postion. Now my question is is this a worthwhile to consider getting considering I got the usual mods turbo injectors ecu etc. 270kw , How much more benifet could I receive over the stock manifold?

Hpi make awsome stuff but 1700 for a stainless steel manifold seems like a bit much imo.

You could get a really nice steampipe manifold custom made for less than that and they are like 10x as strong.

Nice manifold but for that price, it better come with a hot japanese girl.

I'm running 315rwkw with the stock manifold, so I don't think this is going to help you much, other than make your wallet lighter.

Ive got a chinese 'copy' of the HPI unit, atm Im heat wrapping it before i install it.

was $300 delivered.

covered it in heat proof paint, and now thick thermal wrap.

inside we scoped it and there are no marks, burred edges, dodgy welds etc inside, very very clean !

nice porting work too inside the 6 runners, outer welds are high quality.

NO, I wouldnt pay $1700. Better off going with 6Boost for $1200 with steampipe.

stainless steel cracks around the T3 flange area after time, $1700 or $300 no difference.

IMO and based on my experience (I've gone through too much grief with them, both chinese SS and custom made heavy pipe) I would not go near any 'fabricated' low mount exhaust manifold on a six cyclinder engine (RB, 2J, 1J with single turbo) especially for street car. Esp the RB25 one...

Simple reason is that they are too compact and there is no where the thermal expansion can go. (ie motor flange runs at cyl head temperature and turbo flange runs at turbo temp. Big difference in temps and thermal stress is huge because the temp differential is high due to compactness of manifold (short runners)...doesn't matter how strong the material is, it will crack eventually...High mounts don't suffer this problem because runners are longer and don't run length ways with the engine flange...

For low mount set up on street car I would use stocker (extrude honed) or hunt down the HKS cast iron manifold. Hard to find but well worth it...

I'm in the same boat, and am trying to find what manifold will be best to upgrade to.

Does anyone know how far from the stock location, the turbo will move, when fitted on the 6Boost low-mount manifold?

It'd be good if I didn't have to alter my dump pipe and intercooler piping too much.

the one I have is only a cm out, 1cm further towards the front of the engine.

tuner was impressed with the unit for the cost,

however all SS manifolds eventually split around the welds to the flange

hence why Ive applied 2 cans of extractor/header 1200F paint, and dble wrapping with thermal heatwrap

.....hoping for a few yrs worth of use

xs-power

post-18854-1263867523_thumb.jpg

RACE MANIFOLD RB25/RB20DET 45MM PIPE DIAMETER

EXTRA HP/TORQUE FOR RB20DET STOCK REPLACEMENT T3 TURBO MANIFOLD

LOW MOUNT T3/T4 6 CYL ENGINES (GREAT FOR SWAP POWER!)

INCREASE YOUR HP EASY Give your car that sporty feel with a touch of class.

This Brand New Manifold will drastically improve your cars performance look and feel.

FITS RB20DET RB25DET

EACH RUNNER EXTRA BRACE, DOUBLE TIG WELDED FOR EXTRA STRENGTH

STAINLESS 45MM PIPES, T3/T4 FLANGE, TIG WELDS / POLISHED

IMO and based on my experience (I've gone through too much grief with them, both chinese SS and custom made heavy pipe) I would not go near any 'fabricated' low mount exhaust manifold on a six cyclinder engine (RB, 2J, 1J with single turbo) especially for street car. Esp the RB25 one...

Simple reason is that they are too compact and there is no where the thermal expansion can go. (ie motor flange runs at cyl head temperature and turbo flange runs at turbo temp. Big difference in temps and thermal stress is huge because the temp differential is high due to compactness of manifold (short runners)...doesn't matter how strong the material is, it will crack eventually...High mounts don't suffer this problem because runners are longer and don't run length ways with the engine flange...

For low mount set up on street car I would use stocker (extrude honed) or hunt down the HKS cast iron manifold. Hard to find but well worth it...

Sorry, my bad...HKS manifold moves turbo a fair bit...Still a low mount though...

I'm in the same boat, and am trying to find what manifold will be best to upgrade to.

Does anyone know how far from the stock location, the turbo will move, when fitted on the 6Boost low-mount manifold?

It'd be good if I didn't have to alter my dump pipe and intercooler piping too much.

But if you are using a turbo small enough to fit on the stock manifold do you actually need to upgrade it at all?

Edited by TiTAN
But if you are using a turbo small enough to fit on the stock manifold do you actually need to upgrade it at all?

If I can get a faster spool with the 6Boost manifold, it may stop me from doing a RB30 conversion. The extra torque is what I'm after.

If I can get a faster spool with the 6Boost manifold, it may stop me from doing a RB30 conversion. The extra torque is what I'm after.

Are you talking about the GTRS? Surely you don't find it to be laggy?

if you go for an RB30 you will more than likely find the GTRS is too small.

It would be interesting to see how the GTRS would go on the 3L, no doubt the .63 exhaust housing would choke it up something fierce and would max out probably around 5500-6000rpm. Still it would be interesting to see the low down power and drivability. If i do the 3.0L one day ill keep the GTRS on there to see what it does, but no doubt it wouldn't stay on there for long.

Edited by PM-R33
Are you talking about the GTRS? Surely you don't find it to be laggy?

It would be interesting to see how the GTRS would go on the 3L, no doubt the .63 exhaust housing would choke it up something fierce and would max out probably around 5500-6000rpm. Still it would be interesting to see the low down power and drivability. If i do the 3.0L one day ill keep the GTRS on there to see what it does, but no doubt it wouldn't stay on there for long.

The GTRS is good, as you probably already know, but it's not as responsive as a stock turbo (probably 500 rpm or so later). So if I can close that gap a little with a decent manifold, I won't complain.

I have the same thoughts on the RB30, I realise you should go a bigger turbo, but I'd be keen to see how it goes with the GTRS. Surely even being chocked up it won't make less power than my RB25, but with a heap more torque low down.

im sure people will be itching to shoot me down, yet ive got an RB30 in the garage ive basically abandoned as i doubt it will really give all THAT much more torque.

Sure enough the power will jump 30 odd KW yet spool characteristics are seemingly VERY similar from what ive seen.

and yes yes HPI expensive it manifold is

The 30 does give much more torque off boost. If someone will let you take a drive of one, you will be surprised how much nicer they are to drive off boost.

Spool wise, my 30 brings my GT35R (0.82 rear) onto 1psi @ 2300rpm in 3rd or 1psi @ 2000rpm in 5th and you get 15psi at 3500rpm.

There is no replacement for displacement if you want to get a turbo on boost nice and early.

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