Engine popping out the exaust constantly on moderate deccelleration. Hearing a slight pinging wene accelerating from idle (occasionally), Died 3 different times throughout the day wene I blipped the throttle in neutral. This was all noticed Saturday. Still has good power, strong as ever on the dragstrip. Thinking maybe just slack in the timing chain. Any second opinions or tips before I tear into it this weekend would be appreciated.

 

sounds like your lean i know on my z when i got my pipe with the stock needle i was at a 190 main to keep it from being lean i got the jet kit and a 25 pilot jet and put the needle on the 3rd clip and have a 160 main runs perfect and does great in drags suprises alot of 450's if you have the stock needle in it i would check your plug

 

Thanks for the reply but I already tried a new plug. And I choked it on deccel to see if richening the mixture helped, it didn't. My sons z is set up identicle and doesn't have any problems. We've had this setup since january with zero problems. Anybody else heard of these symptoms?

 

yea i had those symtoms before but not very bad. I just adjusted the fuel mixture screw and it seemed to work out better. Plus, I think depending on the humidity and things the air and fuel ratio could be off a little bit.

 

I'll do some tinkering and let you guys know. Thanks for your help!

 

Finallygot some time to mess with it today. First I checked the valve clearences, then plug gap, then carb cleaner on intake while running to check for leaks. Nothing worked. So I turned the air mixture screw out 3/8 of a turn and wah-lah, problem solved. I can't figure out why, I've had it set at 2 1/2 turns out for 6 months and never a problem. Looks like you were right bk8800! And you too Stewbing. Thanks Guys! [img]i/expressions/face-icon-small-wink.gif[/img]