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I guess any 'larger than standard' turbos will perform better with an increased capacity bottom end but in discussing this topic I think that 362awkw with 800Nm is quite an achievement on a stock 2.6ltr - yes it is all up & over 5000rpm thru to 8500rpm so the larger bottom 'would' beef up the low rpm...

 

Marko.

Marko,

I wasn't intending to put your car down, far from it actually.

All I was saying was that GT-RS turbos on a standard capacity engine will result in the engine producing LESS torque than a standard turbo setup on a standard capacity engine. This is painfully obvious for some people, but many people won't actually realise just HOW MUCH less torque the engine will make with GT-RS as compared to smaller turbos.

Just as a comparison, the difference between low-rpm torque of Kabab's GT-SS and your GT-RS:

GT-SS GT-RS

70km/h - 2500N 2400N

90km/h - 3800N 2900N

110km/h - 5800N 3200N

Of course above 140km/h (5000rpm) the GT-RS come on song and make a tremendous amount of torque and power, but no-one is doubting that.... It's the LACK of torque down low (tractability off the line) that I was addressing.

I know you can say that ANY turbo upgrade can benefit in increased capacity, but I think it's pretty plain to see that the GT-RS will benefit a lot more than smaller turbo solutions :D

GT-RS turbos are a MAJOR upgrade for the RB26, and it is general consensus amongst the UK tuners who have had access to them for a few years now, that they need a stroker kit to remain tractable for daily driving and are not really suited for circuit racing... If you're just using the car for drag racing, then I guess increased capacity is a luxury, but not a necessity :P

I agree with you Merli, emails can be read in the wrong context :(

I would assume that the majority like bottom/mid range power whereas the minority (such as myself) like top end power which is the same group of gtr owners with single top mounts :)

Who cares at the end of the day really, as long as the car puts a smile on your face & has the capability of making you break into a sweat at times.

They aren't rated at anywhere near 800HP, but even 2530s are more than capable of a 10 second pass...

How come you say that? HKS rate them at 400ps each= 395 imperial HP. The compressors flow over 40lbs/min each. I think John Munro did a best of 9.45 @153mph on the 2835's. Abeit 56 trim compressors, the 52 trim GT-RS ones lose ~3lbs/min peak flow?

Granted they were highmounts but UAS John says that those bling Jap manifolds flow worse than his ported stocker specials, so maybe more could have been in it if the car was equipped with those instead?

How come you say that? HKS rate them at 400ps each= 395 imperial HP. The compressors flow over 40lbs/min each. I think John Munro did a best of 9.45 @153mph on the 2835's. Abeit 56 trim compressors, the 52 trim GT-RS ones lose ~3lbs/min peak flow?

Granted they were highmounts but UAS John says that those bling Jap manifolds flow worse than his ported stocker specials, so maybe more could have been in it if the car was equipped with those instead?

According to HKS's website, the GT-RS and GT2835 have the same size comp wheels :spcow:

size.jpg

I agree with you Merli, emails can be read in the wrong context :)

I would assume that the majority like bottom/mid range power whereas the minority (such as myself) like top end power which is the same group of gtr owners with single top mounts ;)

 

Who cares at the end of the day really, as long as the car puts a smile on your face & has the capability of making you break into a sweat at times.

You're absolutely right there :uh-huh:

Everyone is after something different from their cars... That's what makes it interesting!! :(

Yah, I built my car/Kabab's car for circuit racing and being tough street bully, so everything I did was aimed at getting as much low down torque as possible, whilst still having a respectable top end. Unfortunately I couldn't stretch the budget to accomodate an OS Giken 3.0L kit :) Sorry Kabab!

Granted they were highmounts but UAS John says that those bling Jap manifolds flow worse than his ported stocker specials, so maybe more could have been in it if the car was equipped with those instead?

I tend to agree with you on that statement Chris, 'bling factor' can soak kw!

LOL

Hahaha! Ok, so can we take it one step further to deduce that the Master Power turbos are copies of Garretts, and the GT-RS has the same wheel as the 2835, and Johnny's ported stock manifolds are better than Jap bling.....

To provide a mid-low 9 second car running on Master Power low mount turbos on the stock manifolds! 9's for $900! Bargain.

You're absolutely right there :uh-huh:  

Yah, I built my car/Kabab's car for circuit racing and being tough street bully, so everything I did was aimed at getting as much low down torque as possible, whilst still having a respectable top end. Unfortunately I couldn't stretch the budget to accomodate an OS Giken 3.0L kit ;) Sorry Kabab!

I'll hold it against you to the grave! :(:) :)

I plotted Marko's torque curve against mine just for interest sake...

Marko's might be alittle off but thats as close as i could match em...

The GT-RS's are making 1000nm torque more then the GT-SS as they are both dropping off which should give considerably more top end!!

torque_compare.jpg

The GT-RS's are making 1000nm torque more then the GT-SS as they are both dropping off which should give considerably more top end!!

thats interesting, the difference in top end kw between the 2 setups is 77awkw (approx. 127rwkw)

thats interesting, the difference in top end kw between the 2 setups is 77awkw (approx. 127rwkw)

The car has made 316awkw on 20-22psi (eBoost was fluctuating at anything over 20psi) on CRD dyno with the same setup plus cams.

Should be good for about 330awkw at 24-25psi with the 260/260 cams and proper boost control...

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