pinking under load

[mojorider]

I am getting some pinking around the 4k rpm range when the engine is under load and its hot outside. I have tried various fixes via my TVR independant but it still seems to pink a bit.

The car is a 98 450 with 44k on the clock. It has been serviced, had a new stock cam and had the pre cats removed, new ht leads, new coil and a mildly modified chip from TVR power.

Where else do I look?

[shpub]

What fuel are you using? Try optimax.

[mav]

either using crappy fuel or it needs the timing retarding

[mojorider]

Have tried optimax, no change. Does not always pink, only on very hot days it seems

[philip_cooke]

If you are using a TVR chip, I suspect it is running fairly lean under heavy load. Try speaking to Mark Adams (do a search - sorry I don't have his numbers to hand) as he markets the TORNADO chip which allows for extra fuelling under load - usually requires a session on the rolling road to sort it though. The chip as fitted to the 500's (nearly) always runs lean at load around 4000 revs. I'm not sure how different the 450 chip is though.

Hope this helps. PS I'll be at Mech Repairs, Cheltenham on Friday to have mine setup on the rolling road with Mark Adams.