Real Garrett Gt3071r (-23 Chra) On Rb25det Results Wanted .

[Simon-S14]

my 3071r gets a tune tomorrow... but its not a -23 CHRA sadly.

still should do alright!

[BHDave]

I'm interested to see how your's goes Simon. I was very impressed with a mates 2835proS and am interested to see if you end up with similar numbers and boost response

[Simon-S14]

the GCG rear housing is a copy of the Pro S rear housing, so in theory i have a HKS turbo lol.

So far seems reall responsive! time will tell.... i'll post up results soon

[Dale FZ1]

My understanding is that the casting is a copy of the OP6 housing. And that was from the source.

A photo of the dump flange area including the wastegate should assist.

Either way, you won't have a dog. Interested to see how it goes.

Edited December 7, 2007 by Dale FZ1

[Cubes]

the GCG rear housing is a copy of the Pro S rear housing, so in theory i have a HKS turbo lol.

So far seems reall responsive! time will tell.... i'll post up results soon

Unfortunately not.

As Dale has said its the OP6 housing which has an a/r of 7. according to Bill down at ATS anyway.

I've attached a couple pics of the outlet of a GT3037ProS and a GT2835ProS.

[discopotato03]

Thanks Cubes , the viewers at home will be able to plainly see the difference in the size and location of the turbine outlet hole . Just in case last night was a big one look at how close the outlet hole in in relation to the sealing groove on the 3037 Pro S (right hand pic) . It really drives home the difference in exducer size between the cropped and standard GT30 turbines . I really would have liked a good second hand 3037 Pro s housing in the smaller 0.68 A/R size but can't locate one for reasonable money , and thats why I'm looking at 2835 Pro S housings and the cropped GT30 cartridges in smaller than 56 compressor trims . At least the 2835 IW housings are availabe 2nd hand from time to time .

As a heads up Geoff Raicer (Full Race in the US) sent me a message yesterday about a twin scroll GT3071R (-23 version) he supplied to a "drift professional" along with his manifold and gates for an RB25 powered R33 . The customer had been using a GT3582R on some form of HKS manifold but was really wrapt with the spool response and torque of the new components . Geoffs been asking for dyno graphs but has none yet .

Anyhow great news but no use to those not wanting to spend lots or use external wastegates .

Cheers A .

[Simon-S14]

my results.... 283 rwkw!

been a LONG day and just about every thing that could go wrong, did go wrong... Got there at 10 and i left at 430 lol... poor Jeff had his work cut out for him but the result is an amazing 283 rwkw's with 11.5 AFR's, 20 psi boost (ouchy i know... overboost issues) and the surprise is... still stock injectors!!!!! Using a malpassi rising rate FPR which bumps the rail pressure up a bit.

started off making 240 rwkw straight out the box... no tune etc, then we hooked up the fuel flow/pressure tester to set up the malpassi... found that the flow was dropping right off as soon as you load it up...the pressure was there but the flow was dying off.

Got a walbro in there atm, which is rated to 500 hp didnt think this would be the prob, but after checking voltages, and changing the fuel filter which was dirty as f**k (looks to be the orig japanese filter) the bullet was bit and a Bosch motorsport was put in, did a few more dyno runs after Jeff changed all the settings and it started going from 250, 260, 270 rwkw after each change... incredible stuff!

boost is spiking to 20psi and theres dick all i can do about it atm.. even with the gate flap held open it stil goes to 1 bar ish. I know a lot of people have had overboosting issues with the GT3037r as they have a tiny wastegate flap, however mine has the much larger flapper and a different rear housing (.71AR) so not sure whats going on there, its not the dump pipe as the flap is opening right out so i think the only thing i can do is to bore out the gate port some more. or external gate.

i also snapped the wastegate actuator arm.... more dicking around on the dyno, umm few other littler things went wrong lol had cooler pipes pop off every 2nd run... fixing that right now, just got home and waiting for the car to cool down lol.

All in all, jeff is tops, turbo tune blokes are awesome, and 25's with 20psi bloody PULL HAAAAAAAAARD!

[_Ryan_]

Great news Simon, congrats!

Is there a thread where i can find full details on your car?

What is response/boost threshold like?

Is there a 3076 that would have good response without the overboost issues, whilst remaining internally gated?

-Ryan

[stolen_s15]

Nice work Simon, sound like a nice little weapon!

Any chance you could post up a dyno graph.

Nick

[Cubes]

Simon.

Awesome result!!!!

My guess is the split dump setup isn't helping boost creep. The flap opens and partially blocks the usual 2" pipe.

The only way to get around it is to either run a bell mouth OR design the split dump as HKS do and match the waste pipe inlet to the flange.

When I get home I'll post a pic of a HKS split dump and you'll see the difference in design.

With my GT3076r (gt3037) I was warned by Sean (boostworx) to run with a bell mouth otherwise I would most definitely run in to boost creep issues using the usual 2" wastegate pipe without massaging it out to the flange which is almost impossible with the xr6t rear flange. I went with his suggestion and its all good. No creep.

[Cubes]

And the HKS dump.

Thanks to the bloke here on SAU that shared these pics with us.

[Simon-S14]

hmm still not convinced its the dump tho... i mean the split dump i have has had a lot of effort put into the wastegate pipe and the pipe and hole is much larger then the screamer, it comes no where near the flap also so the gas has plenty of room to make an exit.

im starting to think that the turbine housing needs to come off and die grind the gate port out more.

i need to get that boost down... 20 psi is a fair wack

[mad082]

ucd15r33 has the GCG version of this turbo with the .63 exhaust housing and he made 251kw at about 16psi, with stock injectors maxing out and only a basic tune on the emanage. he did suffer from a bit of a boost drop off at high rpm. but it was much better than 215kw we made a week or 2 before that when the rear honey comb of the cat has broken away and turned sideways so the cat was pretty much blocked. at open boost it would spool up to 17psi and by 6500rpm it was down to 12psi. the 215kw was made at about 5500rpm and 14psi.

[Cubes]

hmm still not convinced its the dump tho... i mean the split dump i have has had a lot of effort put into the wastegate pipe and the pipe and hole is much larger then the screamer, it comes no where near the flap also so the gas has plenty of room to make an exit.

im starting to think that the turbine housing needs to come off and die grind the gate port out more.

Sounds like you've done well then, not just the usual slap bang split effort.

DYNO SHEET OR BAN!!!

[Simon-S14]

[BHDave]

you've got to do something about that boost response Nice peak, now you just need to get the full 20psi in earlier and fill in the mid range hole.

If the early ramp up onto boost is anything to go by you should be able to gain heaps of midrange.

[Simon-S14]

yeah i know, the acuator is backed RIGHT off, as in its bearly holding the flap closed atm (no preload) as with preload it ramps up and spikes to over 20psi.. so this is the only way we can keep it safe atm.

once the overboost issue is fixed, prweload added, the thing is going to ramp up shitloads quicker..

however as it is, it drives well, and doesnt break traction at all lol

[Dale FZ1]

boost is spiking to 20psi and theres dick all i can do about it atm.. even with the gate flap held open it stil goes to 1 bar ish.

Looking at the graph, it seems to me that boost isn't "spiking" as much as taking a leisurely ramp up to 20psi where it's holding steady over a fairly wide band at higher rpm. The initial knee is pretty much the same shape as a stocker, which points to good/easy/quick response.

That it is holding so steady at 20psi (once it gets there) makes me think it's not necessarily "creeping" either - if there was a problem with adequate venting of waste gases then you'd be more likely to see it steadily running higher and higher. It makes me think that the control of turbine speed at that level is actually quite effective.

All of which leads me to ask: what is the actuator rated at; and what (if any) additional system are you using ie. turbotech pneumatic bleed, EBC, etc? Maybe there's some change necessary in that area? Like BHDave said - sort out that mid range area and it'd be hard to knock.

BTW, top result - the peak number is about 15 - 20kW higher than I'd have expected one of these units to achieve. I'd had comments from GCG that your specs should yield somewhere near 280ish, but I wasn't convinced it could. Thanks for sharing the results.

Now all I want to see is how Gary Dawson gets on with his, and for you to sort out that boost control with further feedback of on-road and on-track experiences.

cheers

Edited December 9, 2007 by Dale FZ1

[BOZ22N]

Just a quick question why isn't anyone running an external gate? this would solve your boost problems.

[AntsRB25]

my results.... 283 rwkw!

been a LONG day and just about every thing that could go wrong, did go wrong... Got there at 10 and i left at 430 lol... poor Jeff had his work cut out for him but the result is an amazing 283 rwkw's with 11.5 AFR's, 20 psi boost (ouchy i know... overboost issues) and the surprise is... still stock injectors!!!!! Using a malpassi rising rate FPR which bumps the rail pressure up a bit.

started off making 240 rwkw straight out the box... no tune etc, then we hooked up the fuel flow/pressure tester to set up the malpassi... found that the flow was dropping right off as soon as you load it up...the pressure was there but the flow was dying off.

Got a walbro in there atm, which is rated to 500 hp didnt think this would be the prob, but after checking voltages, and changing the fuel filter which was dirty as f**k (looks to be the orig japanese filter) the bullet was bit and a Bosch motorsport was put in, did a few more dyno runs after Jeff changed all the settings and it started going from 250, 260, 270 rwkw after each change... incredible stuff!

boost is spiking to 20psi and theres dick all i can do about it atm.. even with the gate flap held open it stil goes to 1 bar ish. I know a lot of people have had overboosting issues with the GT3037r as they have a tiny wastegate flap, however mine has the much larger flapper and a different rear housing (.71AR) so not sure whats going on there, its not the dump pipe as the flap is opening right out so i think the only thing i can do is to bore out the gate port some more. or external gate.

i also snapped the wastegate actuator arm.... more dicking around on the dyno, umm few other littler things went wrong lol had cooler pipes pop off every 2nd run... fixing that right now, just got home and waiting for the car to cool down lol.

All in all, jeff is tops, turbo tune blokes are awesome, and 25's with 20psi bloody PULL HAAAAAAAAARD!

Hey Simon

Are you still running a the R32 ECU or did you move to a power FC? I am just in the process of tuning my 25 with a 32 ecu also.

Cheers Ants