when ever i hit 6k in any gear it feels like the car is bogging or missing, i also am running lean, i have platmun spark plugs, ive searched and i think i need colder plugs or somthing, can anybody help me out thanks

 

Make sure your timing is set, you will need an adjustable cam gear in order to make sure your cam timing is set to your ignition timing. (when you put on the cam gear, it will force you to rotate the cam 1/2 tooth to make everything line up).

a range colder plugs wouldn't hurt either.

 

I would get rid of those plugs and use some regular copper NGK's. If you compare the metal that provides the spark, the platinum ones hardly have any metal. They always seem like a weak spark to me when I have used them.

If you are running lean, then maybe you are running out of fuel at the higher rpm. Fix that. Check your fuel pressure. Check your timing.

If you used a Z6 head then your timing is off by 1/2 a tooth like d357r0y stated. Cam gear.

 

i have a adjustable cam gear, its set to 5 degrees retarded, how do i know if the plugs are colder

 

1. set the gear to 0°
2. set your ignition timing to stock.
3. go to the local parts house and ask them to look up the spark plugs for the head you have.
4. ask for 1 heat range cooler (and get the copper like 4drEF suggests, they put out a fatter/hotter spark). The cooler plug will help in preventing detonation.