RB30 Which Turbo(s) For Road / Occasional Drag Use

[peatough]

Hi


Am about to embark building a RB30. Question is what turbo
to go for. Whether to keep existing 2530`s or go for something
like a T51.

Considered a T04Z but hearing that you can run almost as much power with
2530`s.

How does a T51 boost on a RB30 ? Car will have 272 I/O cams with some headwork.

Regards

Pete

[GT-R Glenn]

IMO the 2530's would spool up almost instantaniously but run out of puff at the top end.
might make mid 600's
To4z would be really good, spool up quick and make 700+
Dont know anyhting about t51's on 30's.
look on the au forums under "Forced Induction RB30"
should tell you everything you could ever need to know

[GT-R Glenn]

Rb30 Hybrid Upgrade, All Dyno Results - Skylines Australia

[peatough]

Glenn


Many thanks for the info - Appreciated

Regards

Pete

[Hugh Keir]

I have used the following turbos on my OS Giken RB30

HKS 2530's - great for driveability but ran out of puff when driving up the revs.

HKS GT-RS - great full stop - would spin all four wheels on a damp road at 90 MPH in 3rd simply awesome.

HKS 2835's - great turbos but I had now decided to chase the power and felt that they were still running out of puff at 8000 RPM.

HKS 3037S - now you are talking not that much lag and simply astonishing power in any gear. It accelerates in 3rd, 4th 5th and 6th in much the same stunning eyewatering way.

Check the vide on my signature to see how well the car drives off boost.

Cheers

Hugh

[R.I.P.S NZ]

Hugh, have you done the 3000rpm to 7000rpm in 4th test and the 3500rpm to 8500rpm in 5th test? Be interested to hear how quick you can do it with the 3037s.
Sparks TO4z RB30 did the first test in 5 seconds and Ludders GT42 RB30 did the second test in 10 seconds.

Both tests start by cruzing at the beginning rpm then nailing it, NOT nailing it at lower rpm and starting the timing as you pass the start rpm point.

Rob

[bazh]

Originally Posted by R.I.P.S NZ

Hugh, have you done the 3000rpm to 7000rpm in 4th test and the 3500rpm to 8500rpm in 5th test? Be interested to hear how quick you can do it with the 3037s.
Sparks TO4z RB30 did the first test in 5 seconds and Ludders GT42 RB30 did the second test in 10 seconds.

Both tests start by cruzing at the beginning rpm then nailing it, NOT nailing it at lower rpm and starting the timing as you pass the start rpm point.

Rob

Rob

What's the MPH values for the tests?

Barry

[Hugh Keir]

Rob,

I've not carried out the specific tests you refer to. I have not seen them discussed before so would not have been able to judge the results in any meaningful way.

For driveability mapping and ballpark boost mapping, I always get Rod at RB Motorsport to get the mapping right, his backside and experience make it hard to improve on, despite having made many attempts with dynos and road mapping, Rods road tuned map always seems to make the car feel right.


When doing the final full boost mapping on my car, I take a close look at the in-gear acceleration figures and overlay the datalogged runs before deciding on whether to change the fuel or the ignition.

Here is the sort of thing I mean. The runs were a few weeks apart, but it allowed me to look back at how the mapping has changed the results.

Clearly the car is faster on the black trace, but you can see that the ignition timing is erratic and getting towards the limit for that setup.

You also get time on the bottom of the trace, I record the data points 200 times / second so it would be pretty easy to get the numbers you refer to if the car was still on the road.

Cheers

Hugh

[peatough]

Hugh


Many thanks for the info regarding the various turbos
you have tried on your OS RB30.

The gt rs look appealing to me as these are said to be well suited
to the RB30. Hugh : Have you got any dyno data with the turbos you
fitted through development of your OS RB? 2835`s and 3037s also appeal but lag may be my concern especially for road use.

Rob : How does the t04z or t51 compare for drivability compared to gt rs twins?

Regards

Pete

[R.I.P.S NZ]

Originally Posted by bazh

Rob

What's the MPH values for the tests?

Barry

It depends on the car, the diff ratio's, tyre diameter etc but its usually about 50-120mph for the 3000 to 7000rpm test in 4th.

YouTube - R.I.P.S Stealth bomber 50 - 120mph in 4th in 5 seconds

To guage an engines torque and response its better to test it from a set rpm rather than a speed anyway.

Hugh, It would be great if you could try either of the tests, especially the second one as your power is similar to Ludders, he has the GT42 and you have the twin 3037s, be interesting to compare if you get a chance to do 3500 to 8500 in 5th.


Rob

[m6beg]

35/42's the way forward

great on the street.


Mick

[R.I.P.S NZ]

Originally Posted by m6beg

35/42's the way forward

great on the street.


Mick

Somehow I dought that Mick, and I know you are joking, lol, but when she's fixed do the 2 tests above and let us know how you get on.

I'd be doubling those times if I was a betting man, but your car is not built for response and torque, its built for high revving peek power so there's nothing to compare really.

Rob

[Lith]

Originally Posted by m6beg

35/42's the way forward

great on the street.

What on earth are GT35/42s? Do you have any details on the wheels etc? Ever since Mario ran "Veilside GT35/42s" I've not been able to work it out, it sounds like a strange combination.

[P3RV3RT]

Pete, when I get around to do my RB30 Ive been thinking about going single. Its alot easier to work on with the space and Im sure you will save a few Kg's LOL

Id also like to go for a 200mph run so I need to work out what setup I need allround to acheive this. My 32 will be mostly track prep'd but still usable on the road.

As for lag I will be wanting to keep it as close to standard as possible.

Bernies GT35R was out of puff at 6500rpm even though it was running 700bhp. Now thats no good for me as I will redline at 8000rpm, maybe higher as I will need the rpm to get higher speeds in each gear.
His new turbo (4094R I think) looks like it starts to run out of puff at 7000rpm, Id be concerned about the lag going any bigger on a single turbo but Bernie and John have said the lag is still minimal on the 4094R.

Hugh, what where better turbo's? The GT-RS's or 2835's? Also what was power and torque differences?

Baz

[Lith]

Originally Posted by P3RV3RT

As for lag I will be wanting to keep it as close to standard as possible.

Bernies GT35R was out of puff at 6500rpm even though it was running 700bhp. Now thats no good for me as I will redline at 8000rpm, maybe higher as I will need the rpm to get higher speeds in each gear.
His new turbo (4094R I think) looks like it starts to run out of puff at 7000rpm, Id be concerned about the lag going any bigger on a single turbo but Bernie and John have said the lag is still minimal on the 4094R.

OK you've given two things, what rev range you want and how much lag you want (as usual, minimal) and already it leans towards a bit of an unrealistic expectation where you want no lag and a huge useable rev range. About the most important thing which you have missed out is, how much power do you want? By the sounds you are shooting in the ~800hp area which is basically GT4094R or twin GT2871R or GT-RS territory.

The trick with wanting to rev to 8000rpm and wanting to make a certain amount of power is that you are running a big motor, if you rev it to 8000rpm without it dropping off then it will need a big compressor to be able to flow enough air to feed a 3litre revving that high. If you go for a big compressor, you are inevitably going to have a reasonable amount of lag.

I think you most likely compromise will have to be the rev range, basically your best bet would be to go for the GT4094R and accept that you will have pretty good response, make your 800hp, but you may not make it dizzyingly near 8000rpm (but then you may). Remember where your peak power is and how it holds on will have a lot to do also with your cams/porting/cam dialling etc - not just the turbo itself.