Detonating At 6000rpm

[_MRR33]

Hey,

I've recently found that my car is detonating (sounds like someones got a handful of marbles and shaking it in there hands) at 6000RPM - Usually only happens when I put the throttle flat if I ease it it won't happen.

It sounds like it is coming from the rear of the car.

The car is a 1993 Nissan Skyline R33 GTS-T, current mods are as follows:

- K & N Pod Filter

- Custom Pod Enclosure

- Cold Air Intake

- Forged Pistons

- Strengthen Conrods

- Blueprinted

- Balanced

- Port Polished

- Metal Head gasket

- Spitfire Coils

- High Performance Timing Belt

- High Performance Spark Plugs

- Gready Turbo Timer

Everything else is stock, including the ECU.

Any ideas of what the problem could be? Thanks.

[khunjeng]

rear end u say?

stock ecu and turbo?

[recce]

Check your timing. Try retard your timing 5 degree to see if that still happen. Might be your fuel (use 98 octane)? What boost are you running? Maybe your compression ratio not right. There are heaps of possibility.

[_MRR33]

rear end u say?

stock ecu and turbo?

Yeah, it sounds like it's coming from the back of the car. Yeah, Stock ECU and Turbo.

Edited April 22, 2007 by ThugishPimp

[_MRR33]

Check your timing. Try retard your timing 5 degree to see if that still happen. Might be your fuel (use 98 octane)? What boost are you running? Maybe your compression ratio not right. There are heaps of possibility.

I'm running 98 Octane at the moment, have run 100 Octane (V Power Racing) never anything below 98 Octane however. I'm running stock boost at the moment also.

[wolverine]

if you know it is detonating then you need to look at engine management.

aftermarket ECU and tuning is the best answer.

Edited April 22, 2007 by wolverine

[_MRR33]

if you know it is detonating then you need to look at engine management.

aftermarket ECU and tuning is the best answer.

Yeah, thats what I need to do. I've got a 3" Cat-Back Exhaust, Bleed Valve and SAFC2 sitting here ready to get installed and I should be buying one of the Front Mount Intercooler Kits from one of the Forum sponsors. Then get it all tuned, and dynoed - I think thats my best bet.

Might even chase after market Fuel Pump.

[fEkuaR]

Aftermarket fuel pump is a good idea mate. That could even be causing it to detonate if the standard pump is failing to supply at 6grand wot +, when did you change your spark plugs last and to what gap?

[Abo Bob]

Check your timing.

[Risking]

^^^^^ couldnt agree more

[_MRR33]

Aftermarket fuel pump is a good idea mate. That could even be causing it to detonate if the standard pump is failing to supply at 6grand wot +, when did you change your spark plugs last and to what gap?

Spark plugs are fairly new, I think it's 0.8 I'm not 100% sure but it's the NGK Platinum ones.

Check your timing.

Will do

Thanks for everyones help.