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11psi would only be safely achieveable with a FMIC...

Just FYI my tuner today said he reckons 12psi without a cooler and 14psi with a cooler is OK with the stock GTt turbo, so I guess what I said above was NQR.

Looks like its my ignition system that's now robbing me of power (i.e. and allowing to only run 9psi).

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Well I think you should find yourself a different tuner. 14psi with stock turbo is just asking for trouble. I guess he's hoping you blow it and then go back to him to install a new turbo. Extremely dodgy advice there.

To answer your previous question, I noticed no heat soak. Also the tune was done off the car.

No noticable heat soak? I take it you still don't have a FMIC...?

After that comment I'm really leaning against one. Maybe just fix my dodgy coil/ignition issue, get a Power FC installed and tuned and then re-asses. I know if I go a FMIC I'll cop another tune, but from your comment I can't really see the point (for me - as I just do the odd squirt and don't need consistent performance)?

Update - just picked up a Power FC.

Getting installed and tuned tomorrow.

Will do a little before and after write up with my R34 + full exhaust + Power FC with stock cooler.

I'll be happy if I get 190rwkw, but I'm secretly hoping for 200rwkw.

It's all happening so fast! I really need to take note tonight of the 'before' picture. What do we want to know? I can think of:

1. Boost (when it comes on, how it holds without an EBC).

2. Fuel economy

3. Driveablity

4. Idle / cold start

5. Power curve (low down, mid range especially)

6. Responsiveness

7. Heat soak on stock intercooler

8. Tuner review

9. Dyno graphs (before and after)

How about taking a 20 x 20 grid of your before and after ignition and injection numbers.

I've done that and it's interesting to compare your before and after results.

Make sure your tuner does ALL ranges, not just WOT.

The full tune should take a fair while on the dyno.

Don't be afraid to tell him to lean out the cruise to about 15:1 and make sure it's lean as buggery so you can get great fuel economy.

Make sure he tunes the 1-2-3-4-5-6 cylinders to be a little richer at cylinder 6 than at 1.

But yeah, doing a 20x20 grab of your numbers is cool,

Good advice. I will be speaking to him about that, I don't want a high max power with crap fuel economy. The tune will take 2 days, as the tuner said in order to do the cold start 100% you need to do a real life cold start. He said he could get it 99% right if it were just a 1 day tune.

Leaning out the cruise sounds like a great idea. I'm hoping he'll be doing that anyway, but it doens't hurt to re-iterate it. It's getting done by Ben @ Racepace, who has come highly recommended and has done some great work with friends cars.

Oooooohhhh so excited! :PBJ:

If you are getting it done by Benno then you will not have a single problem in the world.

Put in it the fuel you normally use.

Drop it off, don't call him, he'll call you.

He'll tune it very very well, he's the best. He's the only one who tunes mine.

Hahaha, that's good - cause I have no idea what you're on about!

I take it your happy with Ben's tune?

Edit: whoops, missed your previous post. Great to hear and thanks for the info.

Edited by McCracken

so adding a turbo back exhaust and air filter, it raised the stock boost to 12psi? and its bad for the car? and where did u buy the larger restrictor from? i currently have a pod and jap catback and my boost raised to 0.8-0.9 bar which equals 12psi already, i cant imagine how much it would go up when i get a dump and front...

From what I've read around here, on an R34, stock turbo and cooler 12psi is pushing it. I'd have mine at say 10psi max if you want some reliability. Yes, the exhaust made the car boost 'too much' and it started to misfire. A performance garage put the restrictor in.

Hey Mcracken, get your boost set to 10-11psi.

This should be low enough to be considered just below the danger limit. Of course, the choice is totally yours. You maybe happy with 9psi.

The retune might get rid of the dip.

Get him to check the fuel pressure on full boost..If a bit low, then back to 9psi for you I'm afraid... and a need for a bigger fuel pump!

Yes. 1 bar = 14.7 psi, so around 0.61.

Yeah, hopefully 10psi after tune, all going well.

Not 100% sure of the restrictor location. I thought it was to the wastegate solenoid or acutator spring or something. I really can't rememeber, I have a novated lease now so I leave all that stuff to the workshops now.

I'm looking forward to your graphs from Benno and his tune so I can compare it to my original PFC tune done by somebody else.

Make sure to post it, and ask him for a graph that goes up to 210 kph on the x axis. Make it easier for us to compare.

BASS OUT

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