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Hey guys, just thought i'd let you know about a new manifold option for your RB25s. my stock one cracked and was warped so it was time for a new one. i had the deliema of all these stories of the any low mounts being shit (which they are until now) and obviously any high mount option would require fabrication of parts and intercooler pipes, posible a new manifold....quite a drama.

anyway i went to just jap to pickup an xforce high mount when i spotted the new HPI low mount manifold.

its super quality, the welds are just amazing, the flange that goes on to the head is one peice and very thick...its just a stunning peice of kit!

the pipe are also a lot thicker and larger than all other manifolds.

the biggest design change is that normally all the pipes head down and then up for any low mount design. here we have all the pipes heading up (where there is more room) and then into the collector...(which is made very nicley too by the way)

THIS WAS EXPENSIVE! over $1300-$1500 for this manifold...but you get what you pay for and whn i see quality like this its worth it. i dont ever want to go through this broken studd, blown gasket, warped bit thing again...and hopefully this will allow me to put this area to rest so to speak...

here is a pic of the manifold from HPIs site. its going on the car today so i'll keep you posted as to how the whole experience goes...

gallery_30866_2266_4827.jpg

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Any chance you took some decent pics while it was off the car? would be awsome to compare them to pics of the cheap manifolds that are out there.

Make sure to take some pics when its all fitted to, im sure lots of people would be interested to see what its like!

i would have but i didnt have time.... this manifold is the first one in the country and just jap only put it on their wall 2 days ago... its now in my car yeah baby!

i have seen lots of manifolds before and also looked at all the ones on just japs wall and have never seen anything so clean and acurate before...

this probably wasnt made by a human...its more machine than anything else....its too perfect!

PS the just jap guys took some pics before they gave it to me so i dare say the'll have some pics once they put their new web site up which they told me is comming soon

The manifold in the photo looks good...I wish you the best of luck with it...

I have had some very bad experiences with low mount tube manifolds in the past and got to the point where I gave up...

My first experience was with a cheap chinese shit manifold...I should have known better but I was a newbie...I am sure many guys have gone down this path. Anyway after about 2 months it cracked. I took it back to the guy who sold it (and fitted it). He able to TIG weld the crack with it on the car. It then cracked again underneath and it had to come off...I pulled it off again and it cracked again...meanwhile a couple of stripped studs new manifold gasket..

I was then given the details (though a major parts supplier) of an alleged brilliant fabricator (also a tech teacher) based in Rutherford (not Lilford exhaust) who could make one for $1200 (due to forum rules I wont name him but if you live in Newcastle or Maitland PM me BEFORE you talk to any guys about making one for you - he is a f**king shonk). He did a good job (thick flange etc) but told me it would be steam pipe and therefore (telling is not a guarantee apparently) that it would not crack...Well it cracked and warped...Once again off the car to be weled and straightened it. When he straightened it he bent one of the runners a very small amount but still noticeable. Anyway it didn't recrack where he repaired it and I thought all is good BUT it later cracked where the runner was bent...I went back to see him and he told me it was now 6 months old and the only thing he would do make another one at cost. He told me I probably didn't tension the nuts properly or put a hose on it WTF??..No way!! By this stage I had gone through 2-3 manifold gaskets and done countless thread repairs...Unfortunately it was a cash job so i didn't have much recourse - But once again PM me before you get anyone in Rutherford or East Maitland to make you one.

I now run an HKS cast iron manifold with seperate runners that for some reason HKS dont make any more. I bought this manifold second hand from wreckers in Japan and it is awesome...It came with 60mm HKS wasegate that fits to the top of the manifold via a flange that is made for that WG...Fitting it was easy even to the RB30DET...Just had to grind small amount off the base of the flange so it didn't hit the RB30 block.

Hopefully the HPI one is better...Part of the problem is that an RB25 low mount manifold is long and thin and the runners run longways. The main flange runs a lot cooler and the long runners esp at the front expand a lot more then the flange and they have no where to expand...High mount manifold dont have this problem..

My advice is go for a Cast Iron manifold for street or everyday use until the HPI manifolds are proven...

they are all good points....

you guys are lucky i am willing to be the gunnie pig to test this in a real world street environment...otherwise there is no way of proving them is there....without buying one...

No probs..

I suppose the point I was just pointing out what can happen if you are a newbie...

The HPI ones might be great and only time will tell. And your right ssome has to try them...Also Just Jap is a good reputable supplier and I am sure if you have any problems they will help you out..

yeah time will tell gents...

steam pipe is good but it will stiill crack...hell my cast manifold cracked!

steam pipe needs to be custom made and I don't think there is a low mount option.

so I would have to wait a few days or even weeks... leigh ws gonna make one quick for me which was very nice of him....still $1300 for custom but I think it was gonna be high mount. now I don't have to change any pipes so its far more cost effective.

Good thing about exhaust manifolds they generally fail just by developing slow cracks that are easy to see and detect so if you do have one fail it doesn't end up being damaging anything else...apart from your wallet for the cost of the manifold and a new Nissan gasket...

As far as pulling the manifold off and putting it back on I can now do it in my sleep I have done it so many times... Its a low mount though and every time I do it I swear next car I do will be a high mount!!!

Best of luck with it and will be quite keen on hearing how it all goes, so make sure you keep us informed.

i have also had bad luck with manifolds as after my original cracked i bought a SS through a reputible supplier, and had about a 20kw loss in power and only after a week i had blown a hole through it and when pulled it back off there were countless cracks through it, luckily they reimbersed me with a standard manifold and cost of replacing it.

ok update on this...

due to the fact that on this manifold the pipes come up instead of going down, the blow of return pipe has had to go as this was a hard pipe, so now its time to manufacture a new intake pipe, but at least this will now be metal so as to not 'crush' under high intake suction from the turbo...should flow better too!

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