Why is it pinging??

[crowey]

As the subject says.... Why is it pinging??

I had the engine done only about 10k ago, and if i dont run it on Premium, it pings. and on a hot day it will ping on premium!

Can anyone suggest anything?

I tried to check the timing but couldnt find the mark.
Other than that i have just replaced the O2 sensor, plugs and leads.

[murcod]

Try retarding the timing a bit more- like try running 1-> 2 degrees BTDC instead of 3. Hot weather and hills in 2nd and 3rd gear will cause it in mine. Also, don't floor it in hot weather up hills.

You could try disconnecting the sub vacuum advance and blocking it off. The distributor has two vacuum advances on it- one operates off the manifold vacuum; the other is taken off the throttle body (near the opening of the throttle butterfly) and increases the timing at slight throttle openings to improve response. My theory is that when you floor the throttle, the sub vaccum advance doesn't retard the timing quick enough- causing the detonation. I've been meaning to disconnect mine and see what happens.

Another option is to run water injection. I've got a system on mine three quarters finished, just need some time and motivation to finish it off and see how it runs.

PS: Are you using normal premium or 98 octane? Try BP Ultimate- I've found that the best. Also check your spark plugs are the correct heat range.

[built4thrashing]

what he said.


timing marks are a pain in the arse to see but if you put a white mark on both the marker and timing mark on botom pulley its alot easier