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On tuesday picking up my r33 gtst after weeks with the mechanics. Had a turbo upgrade did pump and injectors etc... I have done everything that is possible to make this setup run at its optimum, only thing is that i cant get my power fc tuned for approx 10 days. My question is is it safe to drive with standard computer on 7psi boost till i get it tuned? can i still give it a bit when driving, dont want to run lean...

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When I upgraded my turbo, on the stock ECU the motor would ping as it started making boost (because the surge of power was much more sudden I assume, as well as more air at low boost etc etc messing with the maps). I had to knock around 5 degrees out of the base timing to stop the pinging, which made it not real nice to drive, but got me by until I swapped the ECU shortly after.

BUT... you've done the injectors too. Depending on how much bigger your new injectors are, to the best of my very limited knowledge the car will be a pig to drive and will foul plugs in no time. If you give it any stick, it'll piss black smoke out of the exhaust, and your fuel economy will be terrible. If they're a lot bigger, the car probably won't run. You say you have a PFC though, I cbf looking up the exact wording but there is a setting (something like 'Ign Inj Corr' I think) you can adjust to play with your base timing and compensate for injector size. If you absolutely must drive the car, adjust the injector duty cycle down until it runs acceptably (but be careful not to lean it out too much). Keep in mind that you'll need to do this every time you drive the car, as they're reset to zero when you turn the key off.

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You could take it for a run and put the PFC into monitor mode (where you can see the readings for rpm, injector duty cycle etc on the screen). After you've given it a strap, press UP on the controller, which will show you the peak values. If the number is higher than, say 30 or 40, back the timing off. The warning light (check engine light flashes ~10 times/sec) doesn't come on until about 60, by which time it's audible.

You should be able to drive it around, but take it easy and keep an eye on it.

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