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Tweakit 3076r Rb25 Bolt On


Depta
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Contemplating whether to get this turbo, looks like the one from horsepowerinabox and tweakit are very similar except tweakit has these for like $300 cheaper. Does anyone have either of these installed, whats boost like, laggy/spike?

Planning on running around 14-16psi with supporting mods, want 270-280rwkw, is this possible?

I want the bolt on option because already have a new dump and ex. manifold.

Any advice would be much appreciated before i fork out the dough.

Thanks.

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Try a couple of searches, but some threads over the past 6-10 months or so indicated people were having a few problems with adequate boost control. Comments were generally directed towards boost creep (rising with revs, rather than hitting a target and staying level). It may be an issue limited to particular turbine rotor : housing combination so you'd have to inquire with those users which particular spec cartridge was used with their turbo.

FWIW, the cropped 56.5mm version of the GT30 turbine comes in an 84T and 90T spec. I don't know for sure, but suspect the 90T would have better venting and flow capability than the 84T. But there is a fair bit of science in getting the match right between rotor and housing so that internal aerodynamics work ok.

Regardless of who you're buying from, the advertised "bolt on" units are evidently built around a copied version of the OEM Nissan/Hitachi OP6 turbine casting as used on the Neo RB25 and VG30DET. I believe there are other sellers in Aust besides those mentioned who are shifting the same product. Due to the mix'n'match of rotor and housing, it is viewed as a wildcat and there is not likely any technical info available from either the seller or Garrett.

Worth doing a bit of searching and maybe a PM or two to those owners to see how they ended up working out. Let us know how things go please.

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A huge grey are exists between black and white on this specific topic .

The sad fact of life is that a "bolt on turbo" is often a unit thats been compromised in an effort to make it "bolt on" in the std location .

I can't think of any production vehicle that ever came factory std with a Garrett petrol spec GT3076R , the fact that the water/oil/air plumbing is totally different to anything Nissan have on any of their engines tells me that they won't "bolt on" .

Generally the most difficult part of any non OEM turbo is making it fit between the std exhaust manifold and exhaust pipe/dump pipe . All sorts of bastard hybrid things are out there but few are designed to work as the turbocharger manufacturer intended them to .

Once you go to a non std exhaust (or compressor) housing you've changed the turbos configuration and it won't operate as the manufacturer advertises - in other words throw away all the compressor and turbine maps for that unit because they'd now mean zip .

To me staying with a std (or copy) Hitachi turbine housing has serious limitations if you want the best results . Really making a dump pipe for the Garrett IW GT30 turbine housings can't be that hard and at least then you'd know that the turbos turbine and housing are the critical matching set .

A real petrol spec GT3076R is an ~ 500 Hp capable turbocharger at its limit , I find it very hard to believe that the Hitachi 3 litre turbine housing (OP6 type thing) can handle anything like 500 Hp worth of exhaust gas so I can't see why anyone would want to go there with one .

Just a note on my expectations of that turbo , I mean 500 with its largest 1.06 A/R genuine Garrett GT30 turbine housing and don't forget it has the largest available (56T) version of their GT37 compressor wheel .

Now I can't say that the particular bolt on version you're looking at won't work , I strongly doubt that it would get anywhere its potential so hence the grey area .

One other thing I haven't mentioned on this board before , the only Hitach copy turbine housing I ever looked at was not real impressive compared to the real thing . When the waste gate flat valve was open its passage was partially blocked by what looked like like to me at the time an undersized main passage . How or why this is I don't know and I havent seen one since to see if they've improved . It's this sort of detail you can't see with the turbo in place .

Another problem I have is that those aftermarket housings have been "intended" for std and up to GT30 turbines and I can't see how they make a properly formed turbine nozzle function with different sized "holes" in the center of the housing .

To me turbine families are matched to turbine housings with internal shapes to suit that turbine family .

The stand out seems to be GCG's BB Hi Flows and no I don't know why , they are arguably one of the few bolt on Hi Flows that seem to work well - provided the rest of the engine is tuned to suit .

I think the bottom line is that if you truly want to run a GT3076R you need to run Garretts matching GT30 IW T3 flanged turbine housing (3 A/R sizes available BTW) . Really the only extra thing to make is the dump pipe because everything else besides the mounting flange is non std anyway .

Cubes , Mafia here and a few others have done it and there are some long threads about it here too .

As Nismoid would say do a search , cheers A .

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Thanks for the input guys, and just so that u kno, i hav ran various searches and spent hours reding through info on the turbo. I just wanted to see if anyone has used one of these turbo's from either of th suppliers and the results/problems that they got from it.

Thanks again.

Now my next question would be would i be better off re-building and hiflowing my standard turbo than buying one of these?

Or do i cut my losses, sell the dump that i just bought and buy a garrett turbo with the original housings and get a dump made up?

The latter seems to be the better option its just a matter of who do i get to make up my dump pipe, or are there people selling dumps to suit the garrett turbine housings?

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