Rb30det, Tune On Stock Rb20 Turbo

[Cubes]

Hi ppls,

I got the RB30DET tuned up today running the stock RB20DET turbo on the stock actuator pressure.

Boost peaked at 12psi and made 100rwkw by 2000rpm, boost then quickly dropped to 11psi, held for a little while, then tapers off quickly, by 4800rpm boost was down to 9psi where it made 176rwkw.

Not too bad for 9psi.

The tune was only a 1hr tune. AFR's were adjusted to 12:1.

By 6000rpm the injectors were hitting 100% duty with 12:0 afr's.

Quite a bit of timing had to be pulled over 4800rpm, Shaun the tuner said it was due to the backpressure of the stock turbo.

The exhausts dump pipe is a little bodgy which wouldn't have helped the back pressure issue.

[Bl4cK32]

good to see.....now im off to get mine tuned

how does it feel...seat of the pants?

[paulr33]

thats an awesome result for stock turbo. at the same power you posted where yours made 100rwkw by 2000 my stock rb25 was making 100rwkw by 4500 with a total of 141rwkw

[Cubes]

Seat of the pants, it feels stronger everywhere and feels much much more rev happy.

Even though the dyno graph shows it dropping off after 4800rpm it still easily pulls and feels like it is still accelerating hard until 6000rpm.

Shaun told me to change just before 6000rpm.

Definitely quicker than the rb20det running 16psi.

[Bl4cK32]

Thats what i noticed first from the last tune i had, it feels a hell of a lot more rev happy now.....

Thats where he told me to change gears as well....i spose a set of cams will make all the diference

[Cubes]

Its the exhaust housing and compressor causing a lower peak rpm power.

THe compressor is obviously maxing out its airflow and diving in to choke, which is why it is dropping boost.

The exhaust housing is causing a massive restriction which causes reversion, hence reduced VE.

High back pressure in the exhaust manifold lowers VE/Cylinder filling.

Shaun had to pull a heap of ignition timing after 4800rpm as it was pinging really easy.

He said it was due to the small hotside.

Cams with more overlap i think will make it worse.

Hurry and get yours tuned darren. I am really keen to see the difference your larger turbine wheel makes to where peak power is made.

[Bl4cK32]

i meant with a bigger turbo obviously

[Cubes]

Even with a bigger turbo.. Sky30's with stock cams made 290rwkw at 6000rpm.

Thats fairly decent. Very close to where peak power is made on the RB20/25's (6200rpm).

[Cubes]

Unsure what the dip is in torque through the mid range.

Probably a sideaffect from a 1hr tune.

I think with a little more time spent on the tune and a RB25 turbo it will make 200rwkw without any problems.

Would also be interestering if boost drops off like it has with the rb20det turbo.

[Cubes]

I've got a little vid of one of the dyno runs.

Not too much. I was more so watching any tell tale signs of detonation.

[Bass Junky]

I bet you can't wait until you get a bigger snail!!!!

[Skyrine-Dave]

so who;s going to be the first to get their RB30DET tuned with a GT35R.... i want some results

Excellent result!

[mr_rbman]

i thought u had a gt35r joel? as soon as i have my engine stand i'll be able to get started on mine *hint, hint* joel, nah just kidding!

anyway great results on the dyno and its good to see that i'll still be able to have good results using the little turbo while i save up for a bigger and better hairdryer while running her in!

[Cubes]

No GT35R just yet..

I have the custom .82 exhaust housing that bolts up to the stock manifold and has provision for the connection of an external wastegate.

I've got a few things to get yet. Wastegate, CHRA, Comp Cover, Injectors.

I'm still holding off a little on the Comp cover as I am deciding what I really want.

Should I step down the Comp cover to a .5 and go the larger exhaust housing (similiar to the ford xr6t & improve top end VE) or should I go the smaller exhaust a/r with the larger comp cover.

I think the ford setup will suit my needs a little better. All I am after is close to 300rwkw.

280rwkw I would be happy.

I don't know.

[Campster123]

Cubes - Did you build this RB30 yourself and just get Shaun to tune it?

I really want to plunge into this whole RB30 thing as I love a bit of torque but unfortunately while I "know" a bit about mechanics I have really only ever messed with the basics in the real world and so I don't know how much I trust myself... And I don't have all the tools at this stage!

Seems to be a couple of SA guys on the RB30 bandwagon (mr_rbman I'm looking at you!). Maybe you could all teach me! Heh

[Cubes]

I had Chris Milton Engineering rebuild/port/polish the head, Andrew from City Dismantlers (who has now left) rebuild the rb30 bottom end and bolt the head on.

I pulled out the rb20det and dropped in the rb30det in my old mans shed.

I origionally was going to assemble the motor my self but to be honest the cost assembly was stuff all, the expense comes with machining, pistons etc..

[Alf]

so who;s going to be the first to get their RB30DET tuned with a GT35R.... i want some results

Excellent result!

I won't be the first that's for sure, still deciding on what box to use

An excellent result, gives the others going down the same path more motivation to get it done

[Cubes]

I popped out to grab some fried rice for tea. lol Thats my excuse anyhow.

For those interestered.

Boot down up to 4850rpm saw 90% duty cycle, 4.1v on the Z32 AFM and 13 knock.

She broke traction all the way through second twisting the car around when I came off the throttle to grab the next gear.

It definitely has some torque.

Alf.. That flamin' Alf Fisher avtar is shocking.. lol

[R31 POWER]

Hahahahahaha.Good results from that tiny turbo.Does the afm volts seem to not hit as high now with the tune?

[Cubes]

It hits .1v higher, now 4.1v.

Prior to the tune the most I saw was 4v.

Previously I wasn't reving it out, changing up around 3500rpm.

The stock AFM was hitting 4.98v. So basically the Z32 drops voltage by 1v at those airflow levels.

Standard cruise and idle airflow voltages appear to be the same if not very very similiar.

One thing I have noticed is with the Z32 it tends to idle and cruise slightly richer. With the stock AFM it was dead on 14.7:1 both cruise and idle.

Now it tends to sit on 14.2:1 on idle and 13.9-14:1 on cruise, I'm unsure if this small amount will affect fuel economy.

It could be my O2 sensor has decided to kick the bucket as I've fitted the Z32 afm.