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Hey guys just looking at upgrading to GT RS on my rb26 and i am woudering if anyone has them fitted (or ss)so i can come for a ride to feel the lag/power they are making.

Cheers guys.

Would prefer in an R32 gtr as thats what i am comparing it to.

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Wow big difference between the RS and the SS. From everything I've been reading, unless you have increased capacity don't go the RS. I asked a similar question when I was tossing up the 2860R-5 (also known as GTSS) to the HKS GTSS and got no response. I ended up with the 2860R's

Every car is slightly different but I can take you for a spin.

Wow big difference between the RS and the SS. From everything I've been reading, unless you have increased capacity don't go the RS. I asked a similar question when I was tossing up the 2860R-5 (also known as GTSS) to the HKS GTSS and got no response. I ended up with the 2860R's

Every car is slightly different but I can take you for a spin.

That would be great man, i have hks 25/30's ATM and they arnt to bad. The RS are ment to spool at the same point as the older 25/30s due to its newer bearings or somthing. But thats just what i have heard, and if its true i will be useing the GT RS.

However i suspect that the RS's are more laggy its just how much.

Cheers John.

Edit: We should go paintballing again. That was Fun. :D

Edited by BNR32t
That would be great man, i have hks 25/30's ATM and they arnt to bad. The RS are ment to spool at the same point as the older 25/30s due to its newer bearings or somthing. But thats just what i have heard, and if its true i will be useing the GT RS.

However i suspect that the RS's are more laggy its just how much.

Cheers John.

Edit: We should go paintballing again. That was Fun. :D

I have a direct comparison graph between RS's and HKS 2530's...nothing else changed...will scan and post.

I have a direct comparison graph between RS's and HKS 2530's...nothing else changed...will scan and post.

This is only a turbo change but not direct comparison as i now remember they were at different boost levels with different fuels used but you can see that with NOTHING CHANGED they are laggier.

Now the engine was designed and built with HKS 2530's in mind, so the GT-RS's were not able to stretch their legs or come on harder earlier...a GT-RS engine has to be done completely different (you build an engine similar to that if you were running a big single..massive cams porting etc)

also anyone who says they need a larger capacity to be fully effective is just guessing, and not speaking from experience.

post-23582-1200740063_thumb.jpg

My advice...if you have plenty of $$ go the RS route and build a proper engine to suit, they are an awesome set-up on a big $$ GTR engine...or...if its a basic engined street car, go the SS's

also anyone who says they need a larger capacity to be fully effective is just guessing, and not speaking from experience.

I don't think anyone was saying exactly that, what they were saying is that they are laggy without an increase in capacity and your graphs, particularly the first one shows it. On a rb26 motor not specially designed for them they are a lot laggier. Once you build a motor specifically for any add on's they obviously run better.

Not that different dyno runs tell the full story, thats why Keith wanted to test in real life the difference.

I don't think anyone was saying exactly that, what they were saying is that they are laggy without an increase in capacity and your graphs, particularly the first one shows it. On a rb26 motor not specially designed for them they are a lot laggier. Once you build a motor specifically for any add on's they obviously run better.

Not that different dyno runs tell the full story, thats why Keith wanted to test in real life the difference.

both engines are RB26 mate...identical capacity...but 1st one had small cams and little to no head work...not a good match for the turbines...with correct cams and head work you can get these to be just as responsive as 2530's...as now the power comes on almost 1000rpm earlier...and makes power all the way past 9500rpm. Also has a big flat fat 5000rpm max torque curve...did you notice how peaky the 2530's torque curve was?

What im trying to point out is if you only change the turbo's then YES they will be laggier...but if you know what your doing and are going to build an engine to suit them then they can be awesome and responsive...WITHOUT an increase in capacity.

Now we get to the crux, thanks for the input and experience DiRTgarage

I think we are saying mostly the same thing here, but maybe a difference on what acceptable lag is.

1. The GTRS are slower to spool up than the 2530's (you just said that above)

2. The 2530's are slower to spool up than the GTSS (see rb26 forced induction thread)

3. Changing/modifying the head and particularly cams can lower the RPM where the turbo's become effective

The original question of the op is the difference between the GTRS and the GTSS, a huge difference you have to agree. With cams or an increase in capacity the turbo's can spool up sooner, what ever turbo's they are. GTRS for maximum power, drag racing and lagier. GTSS for everyday driving and track work, more response.

From my perspective, I do not consider with all that head work etc and the turbo's coming on full at 5000rpm to be acceptable, I would be looking for 3500 to 4000rpm. With no work done to my engine the turbo's come on strong at lower RPM and with lower PSI. If I could lower my RPM where the turbo's come on that would make me much happier. Cams can only go so far, increasing capacity seems to be the next logical step.

I never say I know a lot but I do read, so has this forum led me to the wrong conclusions above? Everything being the same, would increasing capacity lower the point that the turbo's make power?

I have HKS GT2530's and dumps on my 26 at the moment.

Engine mechanically stock except 260 poncams and cam gears not dialled in, plus all the usual support stuff.

I get around 17psi at 5000rpm, and I think thats 1000 rpm too late, comnpared to R33N1's anyway.

I'd be checking out where your torque band would be too with GTRS compared to GTSS. With 2530's I've lost a fair bit of torque in the 3500 to 5500 range. I've had no real indication of what I should dial cams in to.

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