Change From Gt2835 Turbo To Gt3037 R33 Skyline

[Al]

I reckon this depends a lot on dyno, setup etc. What dyno were you running this one? Do you have high mount manifold/plenum/cams? How much boost?

I must admit I have never seen what these will do on an RB25DET though I am most keen to try and push mine hard at some point. I have seen Hondas/Mitsis getting well over 400whp/300kw @ wheels with these on pump gas on Dynojet and Dynapack dynos and mine has made 280kw @ wheels on pump gas without even really trying.

I am quite confident that I'd crack 330kw @ wheels on the turbo I have (.82a/r GT3076R) on a hub dyno with a decent manifold, cams and a decent hit of boost but the way the dynos read in Oz I'd consider a GT3582R for 330kw really - as much as anything just because a GT30R will definitely be at the high end of its capability on 330kw @ wheels whereas a GT3582R would be humming.

I take it you're from America, the highlighted sentence should read; "but the way the dynos read in the rest of the world, I'd consider a GT3582R for 330kw really"

Americans have their own way of measuring HP, that gives higher readings than the rest of the world.

[Lithium]

I take it you're from America, the highlighted sentence should read; "but the way the dynos read in the rest of the world, I'd consider a GT3582R for 330kw really" Americans have their own way of measuring HP, that gives higher readings than the rest of the world.

No actually I am from NZ. Dyno Dynamics DO seem like they read lower than most other dynos anyone anywhere use - the others are all in far closer proximity in terms of results than the DDs. Mustang dynos (used in the US mainly) are pretty close to DD though. Majority rules, Oz are the odd one out.

Its not that Americans/everyone else have happy dynos, its that your ones are low reading - you'll find that the reason most people who can afford it who are going for hub dynos aren't doing so for the bigger numbers... if everyone measure using the same unit it becomes all comparable, the "bigger than dyno dynamics" measured numbers end up just making it like a different currency.

Because of the consistancy of the use of Hub dynos around the world I can get a good idea of what to expect out of my car - people have tried every set up under the sun in the states, its just a matter of finding it. I know that my turbo on C16 on a good setup can make 550whp/410kw @ wheels on a hub dyno - and I know what 280kw @ wheels equates to roughly in the real world so I can ascertain that its going to be good if I max it out. I know that people regularly get over 450whp on pump gas with a good setup, or ~335kw @ wheels on a hub dyno - and I know that people with similar mods to me are making around 250kw @ wheels on dyno dynamics.

If I were to use that to make a conservative thumb sucks I'd say the difference is at most around 12% between a DD and a hub dyno from the above comments. If that were so, 300kw @ wheels should be the normal target for a .82a/r GT3076R with a bit of head room on pump gas, or if you are going to be ruthless and put "race gas" into it and crank the boost you should be able to make 360-370kw @ wheels. Those readings would result in very happy cars

[super_s13]

I would be very interested in your 2835 if you were to upgrade.

[WARLORD]

I reckon this depends a lot on dyno, setup etc. What dyno were you running this one? Do you have high mount manifold/plenum/cams? How much boost?

I must admit I have never seen what these will do on an RB25DET though I am most keen to try and push mine hard at some point. I have seen Hondas/Mitsis getting well over 400whp/300kw @ wheels with these on pump gas on Dynojet and Dynapack dynos and mine has made 280kw @ wheels on pump gas without even really trying.

I am quite confident that I'd crack 330kw @ wheels on the turbo I have (.82a/r GT3076R) on a hub dyno with a decent manifold, cams and a decent hit of boost but the way the dynos read in Oz I'd consider a GT3582R for 330kw really - as much as anything just because a GT30R will definitely be at the high end of its capability on 330kw @ wheels whereas a GT3582R would be humming.

hope this answer what ive done.there is more that i have not listed yet.

as for dyno its a dyno dynamic at croydon racing developments

http://www.skylinesaustralia.com/forums/Mo...tml&hl=gtrs

[Cubes]

Interesting thing this up to and around 290-300 Kw . Obviously the RB25 factory exhaust manifold will only go so far flow wise and I suppose HKS intended those Pro S turbos to live within its capabilities . Personally I think a GT3037/GT3076R 56T has more in it than 320 Kw but like most turbos it needs large A/R turbine housings to run it to its limit .

Cubes I would be very tempted to beg/borrow/steal a 1.06 A/R IW turbine housing because I think your 3 liter would be more free reving and with more advanced timing should gain in most areas except the very bottom end where it shouldn't be lacking anyway , what low WOT torque it lost may mean less traction loss at the same time in a RWD car .

Once you reduce the turbine inlet pressure you shouldn't have the IW issues because its the pressure and velocity that goes against integral waste gates , pressure wanting to force the gate open and high velocity meaning the gas not wanting to make the sharp right hander and flow out through the gates hole .

Not my money I know but food for thought , cheers A .

BTW I'll be trying for as close to 9.5 static CR and Pon Cams in my 33 25 because this has not been tried and I think pump fuels and turbos can nowdays cope with it .

Traction really isn't a problem even with it making 200rwkw at 3500rpm and 256rwkw @ 4000rpm. 200rwkw with the vg30det turbo used to be a problem until I pushed in 12mm of cradle rake, new shocks/springs and better tyres.

Now once the tyres are a tad warm second gear only slightly chirps and third gear simply hooks up unless you hit section of road that is a little uneven.

I've had comments it looks like a 4wd the way it lunges away through second and when clicking third.

First gear sure it spins but thats what the 3ltr is for; slightly short shift it doesn't drop off boost it just picks up and goes.

It actually feels like if I were to shove a set of RA1's on the rear I would have zero traction problems and could do with some more boost through the mid.

The 1.06 will feel lazy creating traction problems in wet weather and loose that throttle response/control as the larger turbine housings tend to make all their boost within a smaller rpm window.

The .82 however windmills from basically off idle which makes brisk driving in wet weather and poor road conditions extremely easy.

All though I have not driven a GT30 with both the .8 and 1.06 thats my perception from driving both a GT35 .82 and 1.06 both on an RB30DET.

IMO for the 2.5 ltr .8 rear max for the 3ltr .8-.9 max regardless of the turbo size you are running.

I really think if I went a 1.06 the car under normal driving conditions would be slower. Sure big rpm launch at the drags it might be quicker but thats really not what I want out of the car.

If I want more than 320rwkw but under 390rwkw I've decided the GT35 .82 is not a big step away BUT it requires nice exhaust manifold, inlet and most likely cams with more lift if I don't want to run huge amounts of PULP unfriendly boost.

The way the car is now with ~20psi through the mid from ~3200rpm (when on road, loaded on the dyno it can see 20psi just under 3000rpm) is awesome; tougher actuator and push another 2-3psi in up top I believe it will pretty much max out the combination and should touch 320rwkw. Sure there may be another 10-20rwkw absolute max if I run the turbo well in to compressor choke.

10-20rwkw is not worth the quick spool, windmill and mid range power of the .82 especially if traction is not a problem.

With regards to compressor choke. the GT3076 comp map states ~525hp. 525hp is 391kw at the fly. Minus the usual 70-75rwkw drive train loss at this power level and we have 316-321rwkw. Close enough for me.

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Warlord,

You've spent a lot of $$ on little bits that probably didn't need replacing for your power level.

Mine was a budget performance bang for buck build. I did go a little overboard with having the head ported/polished and valve deshroud but I seriously believe it was money well spent as fuel economy is awesome even with the large cams and it seems to be making more power easier than other rb25det's and r32 rb25de heads on rb30 bottom ends with similar setups.

Hell I'm still running the std coils that were breaking down at 12psi until I siliconed them over a year ago. Now 20psi odd and they are still trucking.

They won't be replaced until I have to.

[WARLORD]

i guess you build to your bugged if its tight or not,

have you run your car down the 1/4 yet cubes

only reason i ask is ive got a private day on the 17-8 and was wondering what you get to compare.

[Cubes]

Unfortunately Adelaide is useless. We have no drag strip.

Budget/priorities it is. I've wasted too much $$ in the past on cars this time around I decided to do it for as stock as looking performance only. Lots of fan dangled bits this time around does not interest me.

Hence the build of the rb30 and R32 chassis to obtain absolute max average power in a light weight car and everything literally looks 100% stock.

As power goals continually increase and the car is just a weekender I'm really considering the purchase of a cheap tidy 4door R32 GTS4 and dropping an RB30DET in to that with a nice little GT4088r and setting it up for track only, it will be street driven but chances are won't last long as they are hot on defects here in SA.

I have yet to hit the dash with a vid cam @ 302rwkw as its still a little hairy but previously with a little over 260rwkw it would zip to 100km/h in a shade over 4secs by idling it off the line. No big rpm launches. It would then go on to hit 180km/h in ~9secs. Unsure if you run a Z32 afm but for reference mine is hitting ~5volts.

[SLY33]

cubes, we should meet up when im back at the end of the year, id love to check out your 3litre, might convert me over dropping a 26 into it!

would be good fun to do some rolling run comparisons as well, and hopefully my gtr will be on the road by then too!