ok i have an L98 with a zz4 cam,shorty headers,custom Y and 3inches out the back, i have a built 700r4 with a 2000 stall, 2000 ss 3.42 rearend. with moderate driveing(not hard but not easy) bolth freeway and street im getting 8mpg do i need a dyno tune for my car????? thanks

 

Your car is out of tune. Your stock tune is not compatable with your new combo. A custom tune will give you more power and improve all the overall drivabilty of your combo.

 

A new chip with a custom tune is a must. Without one, it's actually possible to damage the engine because the fuel mixture is so far out of whack.

 

thats what i was thinking just wanted to clear it up and its carbed by the way

 

Are you still using the stock CC distributor? If so it will be stuck in "limp home" mode. You need a vacuum advance distributor. And welcome to the world of high performance engines. That cam isn't going to get you but 15 or 16 MPG with a good tune. If you have a non-cc distribuor then check the carb. Which one BTW?

 

There is CCC hack information on the DIY PROM board here.

Also zz4 cam isnt really wild at all, the CCC stuff should be more than adequate to make it run rather well.

How ever it has to be in proper mechanical and electrical tune.

I would tend to think you have something else wrong that you think you dont.

Anyhow you tune a CCC carb just like any other carb on the secondary side.

Give us what info you can.

For what its worth GM had a complete ZZ$ swap kit available for the thirdgen at one time, chip included :-)

later
Jeremy