GTRS turbos on HKS 2.8

[sly33]

hi guys, im rebuilding my rb26dett with a HKS 2.8 step 2 kit, and having a hard time choosing turbos. Most people down here in Aus are saying GTRS's will still be too laggy for decent street use, but that you boys have been working with the GTRS's for longer than we have.

any feedback on these turbos on a 2.8 or even a 2.6 would be great. I also have access to some HKS 2530's which are probably my next choice if the GTRS's prove to be a bit large.

Single conversion is out of the question due to modifying laws in my state, so must remain low mount twins, and preferably HKS as i have all the HKS dumps/downpipe setup etc..

any recommendations for my setup regarding cams, compression ratio or anything else will be greatly appreciated!

thanks for any help, Allan

[blueskygtr]

All you need to know on this thread mate
Read and enjoy

disco potato

Jay

[sly33]

thanks, i read through it all, some good info and good links. Not really any info on 2.8l setups tho, and apart from some garret equivalents (which personally ive always steered away from) nothing on the GTRS.


Anyone got results of a 2.8Litre? esp with GTRS's??

cheers

[bladerider]

GTRS's are meant to have been optimised for the 2.8kit by HKS to overcome the laggy nature of the old 2540's they superceeded.

The way I understand it is they give the same response on a 2.8 as 2530's do on a 2.6 if that makes sense. So expect a bar of boost just past 3000rpm and 1.5bar by 4000rpm I guess - very little lag at all for a pair of turbos capable of 700bhp.

There are discussions about them on here if you try different search words Im sure you will find them.

J.

[sly33]

hi J,

where did you get the info that the GTRS's were "optimised" for the 2.8kit?? This is the first ive heard of it??

cheers, Allan

[hipogtr]

Originally Posted by sly33

hi J,

where did you get the info that the GTRS's were "optimised" for the 2.8kit?? This is the first ive heard of it??

cheers, Allan

From HKS directly at TAS when they were debuted about 2 years ago.

Cya O!

[bladerider]

^^^^^^^^^^^^^^^^^

What he said, although admittedly through a HKS dealer.

J.

[sly33]

That sounds great. Really just need a real life example to confirm this lack of lag! surely theres someone running this combo?

[drewby]

hi sly whot power are you trying to end up with, d

[sly33]

hi drew, im not so much bothered by a power figure, i just want a pair of turbos that will be well suited to the 2.8l engine. ie, looking for the equivalent of the GTSS's for a 2.8. Something that has good boost response for the street but not puff out early at high rpms..

cheers

[Cord]

Have used the GTRS's on a few 3.0 and they are really suited to the bigger capacity. Have also used them on a 2.6 and they weren't so good, boost threshold was quite high (not un-usable) but the main problem is with shuffle. A balance bar manifold does a lot to address the problem, but never cured it 100% on the 2.6. I think they will be good on the 2.8 (but would again have a balance bar manifold to be on the safe side). The 2530's are a great set-up and work brilliantly as a low boost threshold, but still good BHP, set-up for the 2.8.

I suppose either will work fine, just depends what your end goal is.

[drewby]

hi was just guna say they same as cord the 25 30,s on the 2.8 with maybe 264 cams will be very nice & should give you close to 600 hp on 1.4 bar, go get em, cheers. D

[sly33]

if you know who still has gt2530 stock, let me know! as greenline cannot get them anymore! i already have a pair, but they could prob use a rebuild, and ive promised them to a mate... surely there is still old stock of these out there? ive asked nengun, but seem to take ages to reply... anyone know other japan based parts websites?

hi cord, when you say shuffle, you are talking about compressor surge? how bad is it and what rpms does it occur? Is a balance bar manifold just like stock but with a pipe connecting the two before the turbine inlet? where do you get these? Thanks

[Cord]

Balance bar manifold is indeed a pipe joining the 2 manifolds together. HKS (among others) make them. Or you can simply weld a pipe between the two standard cast manifolds (if you're a good welder!) Shuffle is mainly in the mid range and occurs on very very light throttle, ie motorway cruising.

[sly33]

When i drive with my 2530's, i think i get shuffle??! say cruising at 110km/hr, i try to overtake using light throttle, i get this noise as soon as i start to back off, kind of like reversion, but not, wouldnt know how to type it!!! kinda sounds like "SSHH sshh SSHH sshh SSHH sshh" (sshh being a lower pitched sshh-sound, and SSHH being a slightly higher pitched sshh-sound! LOL)

Is that understandable!!? is that shuffle?? i run stock BOVs and i believe the sshh sounds to be coming from the pod filters (i think).
so with your GTRS setup, if your using some decent throttle, the car will come onto boost nice and smooth and wont shuffle?

does shuffle damage or shorten the life of anything?

thanks!