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Hang on sec, this is a different dyno sheet? This shows a noticable difference in where peak power and RPM is at. encouraging.... Now, this is the important bit, is this representing the same engine and what was changed to get this rpm/power spread gain, just the plenum? If it is, this is the data I'm after!

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Hang on sec, this is a different dyno sheet? This shows a noticable difference in where peak power and RPM is at. encouraging.... Now, this is the important bit, is this representing the same engine and what was changed to get this rpm/power spread gain, just the plenum? If it is, this is the data I'm after!

Sorry I thought I had posted that dyno sheet in this thread.. There's currently a similiar discussion over in the rb30det thread. :(

All that was changed was the plenum and injectors. Boost was left the same, ignition was left the same and afr's were obviously set back to 12:1 due to the larger injectors. Time wasn't wasted tweaking to see how much ign could be used to bring up the mid and peak power.

Do note the plenum used was a short runner/gtr style large plenum. Its not one that utilizes the std runners.

I haven't seen one such as the plazman be used on a 30det (how retaining the std runners and only changing to a larger plenum affects power).

EDIT: come to think of it I 'think' I remember seeing a VL RB30DET with a plazman plenum on it that retains the std runners at Boostworx. I will have to check and see how that went.

Unless the dyno operator has calibrated the dyno's indicated speed for the vehicle the speed shown will be out.

Which is evident with the dyno sheets I posted above.

oh, that throws a spanner in the works doesnt it lol

And it only takes about 30 sec, although i have found that there is some discrepency when setting up the ratio tacho on the dyno, when doing a power run with heaps of grunt, there is some tyre slip, it only takes 3 or 4% slip to throw out the numbers significantly

dudes give me a break lol

I street tuned the car myself and then hired my mates dyno (for a very good price) and he was not even there to help me set the dyno up (took me 15 mins how to work out to get the ramp runs working properly) hehehe its been over a year since ive operated a dyno last and i forgot!

it was 7000rpm when i backed off - i backed off when it hit limiter.

keep in mind that was only 15psi (engine can do 25psi cos of low compression) and it was 38 deg in the room SOOO hot. so i did not like pushing the engine sooo hard.. i let it cool down a bit and ran this number which is pretty good but i backed off cos it was knocking over 50 because it was wayyy tooo hot.

dyno1.jpg

The Standard RB25 inlet manifold is fine, very good even! We have RB30/25's with GT3540 .82 making 350kw @ wheels on 20 psi pump gas no problem. Power peaks at around 7000rpm and hangs on nicely. The gains are to be had on the exhaust side. 3" aint gonna cut it at those power levels. A lot of GTST guys run into trouble as they slowly upgrade. Bigger injectors, bigger turbo, 3 litre bottom end, all supported by bolt ons (intercooler, exhaust etc) only ever intended to make 200-250kw. Check the VCT is working correctly and the cam timing is correct also.

Cheers.

mine has a 3" exaust and it does not cause me any issues.. i am looking for around 320 - 350rwkw

Power curve is looking nice.

See how it goes as you wind up the boost.

When you have 350rwkw and NO knock, let us know........... :P

Edited by RPMGTR
Power curve is looking nice.

See how it goes as you wind up the boost.

When you have 350rwkw and NO knock, let us know........... :P

RPMGTR,

What are your experiences with the R32 RB25DE Non-VCT head (as the above dyno sheets were of)

hahahaa =) not bad for a street tune.. i did not touch the tune on the dyno i only used it for 30 minutes to run it up and check the tune and everything was fine.. I just wanted to put the power figure to paper... was not using shootout mode...

if this saturday is cooler i might run it up again with more boost see what happens

ohhh it was boiling hot in the workshop.. the dyno sensor was in the air (no where near the engine bay) and it was reading 38 deg so i was not really interested in pushing it anymore

Mr. Squiggle.

Lol Guilt-Toy.. Top stuff. :happy:

Edited by Guilt-Toy

Are you trying to say the engine wont make that much power without knocking?? i need a fuel pump upgrade and boost controller upgrade before i chase anymore then 320rwkw anyway and im not spending anymore money for at least 2 years :happy:

Power curve is looking nice.

See how it goes as you wind up the boost.

When you have 350rwkw and NO knock, let us know........... :P

RPMGTR,

Regardless of power being made.... What your findings are is the RB30DET regardless of the power it makes requires a 3.5-4" exhaust and aftermarket exh. manifold if you don't want power to nose over at 5500rpm?

Its a pity I don't have the dyno sheets but there are a couple of RB30DET's running the VCT head, std exh. manifold 3" exhaust that even though they are only making 180rwkw-220rwkw with std and highflow turbo's they STILL nose over at 5500rpm.

Those that run with a plenum regardless of the power they are making don't nose over early. On the dyno I run on. :S

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