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ok - as pm'ed to Sydneykid:

Firstly, I will describe my car:

Series1 R33 GTS25t

Mods:

HKS EVC4

3" Turbo back zorst

CAI pod filter

NGK coppers @ 0.788gap

Cleaned induction system - AFM, TB etc.....

Ok, when boosting at 3000rpm/0.82bar i get a slight ping, only audible between those concrete barriers on the highway. I turned it down to 0.76bar and its ok. Whats causing the ping at low rpm? I've done a search on SAU and can't really find any specific info applicable to me. The problems i can think of are:

1. Dirty injector(s)

2. Tired fuel pump

(dont think it the first two coz it seems to be ok up high @ 0.76bar)

3. Turbo is getting hot at those low rpms (fix with FMIC)

4. Just bad fueling/timing coz of stock ECU (temp. patch with adjusting the CAS or get an SAFC as a temp. fix)

5. Blow by gasses leaning it out?

6. Try a colder plug (what do you reccomend for my application)

Could I just reset the ECU so it will learn the increased air flows?

Ross, Are you 100% it's a ping? I run BCP7ES plugs, there a heat range colder than the 6's, gapped to 0.7mm. Stock pump could be going, but you'd expect it to happen under full-load. Might be worth getting injetors flow-tested. Blow-by is more likely to happen at high-rpm.

I'd get it on a dyno, and make sure that it is a ping, then look at the AFR's there the most likely indicators:D

Thats the only time it audible - when the sound bounced off a wall. What else could it be? I think your suggestion for a dyno si the best, that way I can see EXACTLY what the problem is. Hate to buy an FMIC and find out it was just a dirty injector eh.....

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