Rynofasho

iTrader: (3)

So a friend and I were out tuning last night and I was seeing some knock from 4000-4800rpms. It was pulling about 3 degrees of timing at peak retard and it was at 27 degrees at the time. Josh and I heard something for sure, but it was difficult to be 100% sure it was actually knocking, especially considering we were commanding around a 12.5:1 AFR and we could sometimes hear a noise even commanding 11.7:1 AFR. Anyways, apparently there are NGK TR55's on the car, not sure of the gapping, but the previous owner told me that FLP (who tuned it initially) was seeing a bit of knock before the plugs were put on. What are some potential avenues to explore? I would think the injectors are alright since it is such a limited rpm range in which it is happening. I feel like it might just be that the exhaust is resonating in that rpm range and it is vibrating against something so its pulling timing. I guess I can find out for sure when I put it on the dyno Saturday. Josh advised me to clean my MAF, so Im going to start there, but what else would you all suggest?

Sorry, forgot to say it is a mild bolt on car. FLP longtubes w ORPs, lid, smooth bellows, 2OTL, and some suspension mods. I guess I could look around for some 100 octane but I dont see why it'd be knocking like so on stock internals and compression. Im running 93 octane currently.

calongo_SS

iTrader: (7)

Put in some 100 octane and see if it goes away. What are some detail ont he car?

calongo_SS

iTrader: (7)

What is the max WOT timing?

Rynofasho

iTrader: (3)

The highest we got was I think 27 degrees which isnt much at all and we backed it down from there between that rpm range.

calongo_SS

iTrader: (7)

It's most likely false knock from or bad gas maybe?? Who knows where it's coming from though...