Jump to content
SAU Community

Recommended Posts

  • Replies 95
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

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...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Input shaft bearing. They all do it. There is always rollover noise in Nissan boxes - particularly the big box. Don't worry about it unless it gets really growly.
    • For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
×
×
  • Create New...