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Hello there,

I am running R33 GTSTS2 with 14PSI of boost.

I am using the standard ECU, not retune has been done.

(But Nistune + Z32 ECU will be installed soon)

At current the car is making 300HP at the cluch.

However there is a bit of a strange behaviour.

Sometime when I floor it rapidly it feels as if the engine has been shut down for a few seconds.

It's quite violent, but no misfires or stuttering.

Then after a second or so the engine comes back to life and everything is back to normal (I have to ease off the pedal though)

In contrast when I floor the pedal a bit more sensitive everything is fine.

For example I can go to top speed with no problem whatsoever ..

Is this R&R?

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Yep that sounds like R&R, 14psi is too much for the stock ecu and you will need a tuned/new ecu to fix that (or lower your boost right down)

Hi!

Thanks ..

Nistune Z32 ECU + AFM is here for the rescue.

I have no idea how R&R feels ... I thought it would be kinda smoother effect.

(It feels like the ECU is actually shutting down the whole engine for a moment)

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I'd be more worried about how long that standard turbo is gonna last at 14psi .. :wub:

(Sidenote - how do you know what power you have at the 'clutch'?)

Hi there,

I 'know' about the power because of the Dyno .. the 300 figures is obviously calculated.

(It's 250HP rear wheel)

post-33912-1278511354_thumb.jpg

post-33912-1278511367_thumb.jpg

post-33912-1278511384_thumb.jpg

Edited by Torques
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Ummm that is a chassis dyno, therefore it's "300hp" @ the rear wheels dude.

Although 300 is a bit dubious.

You can clearly see the big flattening off in the first graph, R&R mode kicking in. Plenty of results around that depict this.

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Ummm that is a chassis dyno, therefore it's "300hp" @ the rear wheels dude.

Although 300 is a bit dubious.

You can clearly see the big flattening off in the first graph, R&R mode kicking in. Plenty of results around that depict this.

Hi!

Thanks for pointing this out ...

But it is definitely is not 300 rear wheel.

At the Dyno they first plotted the higher figure, I guess to impress customers.

Here's (attached) what they said it is RWHP

(I wish I had 300 at the rear)

post-33912-1278510887_thumb.jpg

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Ummm that is a chassis dyno, therefore it's "300hp" @ the rear wheels dude.

Although 300 is a bit dubious.

You can clearly see the big flattening off in the first graph, R&R mode kicking in. Plenty of results around that depict this.

S_HP is predicted flywheel horsepower...

but thats ok because you have never been wrong

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I'm honestly stunned a tuner (and really, anyone who uses a dyno) would even bothering to use the 'predicted horsepower' feature given how inherently inaccurate it's going to be ... it's just going to confuse the owner, really. (But hey it gives a higher figure for the warm fuzzies, right?)

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S_HP is predicted flywheel horsepower...

but thats ok because you have never been wrong

Guess i should open the attachment fully next time to read the fine print, never to worry though when there are people like you are on hand!

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LOL,

This has really become a fun thread.

I like ->

'He is from England'

:whistling:

But ... I am half German, so only interested in real and precise numbers.

I don't know about the inherent formula to calculate 'clutch hp' but it can not be too far off from the truth.

Anyhow, I am aiming at HP 350+ at the rear and hope Nistune was a good investment to eventually get me there.

Cheers from the land of clutchpower,

Andrew

Here are some pictures from last weekend:

Jap Event

Guess i should open the attachment fully next time to read the fine print, never to worry though when there are people like you are on hand!
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Hello there,

I am running R33 GTSTS2 with 14PSI of boost.

I am using the standard ECU, not retune has been done.

(But Nistune + Z32 ECU will be installed soon)

At current the car is making 300HP at the cluch.

However there is a bit of a strange behaviour.

Sometime when I floor it rapidly it feels as if the engine has been shut down for a few seconds.

It's quite violent, but no misfires or stuttering.

Then after a second or so the engine comes back to life and everything is back to normal (I have to ease off the pedal though)

In contrast when I floor the pedal a bit more sensitive everything is fine.

For example I can go to top speed with no problem whatsoever ..

Is this R&R?

It could be that you have reached the Air Flow limiter or "Boost cut", if that's the case its easy to sort out with nistune just open up your bin file and scroll down the bar on theft till you reach "TP Load Limit" set these to "255" or if your using the hex editer set them to "FF" this is maximum sume set it a lower so just above STD

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It could be that you have reached the Air Flow limiter or "Boost cut", if that's the case its easy to sort out with nistune just open up your bin file and scroll down the bar on theft till you reach "TP Load Limit" set these to "255" or if your using the hex editer set them to "FF" this is maximum sume set it a lower so just above STD

Thanks for pointing this out.

I will resolder/rewire the Z32ECU this weekend and dive into the abyss of Nistune :whistling:

I will definitely have questions!

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