I just installed the zz4 cam, lunati hydraullic roller lifters, 7.8" pushrods, cap, rotor, plugs, and it still hesitates. I removed the AIR injection and AC and two of the pipes are still open. Would this cause it? Also no matter what I do it seems my valves still rattle when I run the car. How do I set them so that this doesn't happen?

 

i dont know...but would like to know!! TTT!!!

did you set the valve lash properly and did you preload the lifters?

 

OK, im getting really frustrated. I just took out the lunati lifters and new pushrods and replaced everything but the cam back to stock. and now I can't get the damn thing to start again. I've built engines before but never with a computer, is there anything special I have to do with the timing or anything before this thing starts. Pretend like Im a newbie and tell me everything. PLease, i need the car to go back to school and its been out of commission for two weeks.

 

I see you are running CV secondary rods. Did they help with the hesitation or exascerbate it?

It could be that you need something like a B hanger to compliment the rods. This will pull the rods higher out of the secondaries and allow for greater flow.

If you installed the cam straight up, this should result in about 4* of advance, as this is how cam manufacturers design them from the factory. If the valves seem to be rattling maybe it is a tiny bit of detonation. Try retarding the ignition by 2* and see if that helps.

A lumpier cam increases airflow through the engine and thus demands more fuel. I think richer rods and hanger is the correct way to attack this. QJets will bog your engine if they aren't happy with the amount of flow on the secondary side. There is a good Tech Article on this site dealing with making your cc QJet hum right along.

 

Wait a minute...aren't 7.8" pushrods for a FLAT TAPPET cam and 7.3" pushrods are for ROLLER cams?


Is it are simple as that? The pushrods aren't allowing the valves to close?