Have you spent much time dialing it in? I know someone that had a stock, except for headers, ZZ4 in his 65 El Camino, he ran it with a 700R4 and a mid-3 series gear. It always ran 12.70’s-12.80’s. I’ve also seen guys at the track that couldn’t get ZZ4 equipped cars to run quicker than low-14’s, but that’s more about their lack of tuning and driving skills than the engine itself.Where are all the ZZ4 guys at? Im looking to upgrade possibly. From the stamping on my ZZ4, it appears to be aluminum l98 heads stock everything. Center bolt valve covers. Feels like a turd to me power wise and looking to upgrade with bolt ons.
I moved to the Blandon area from Douglassville, so you were pretty close. Wife still works in Boyertown. Where do you have your dist. vacuum advance plugged in? Timed or manifold vacuum? I run mine from a manifold port. Even after recurving my distributor, it used to hesitate with the timed spark vacuum port.
To be honest with you, I dont even know what your talking about when it comes to vaccum. I understand the concept but have never worked with it before. Ive never even set timing on a motor. Im going to attempt the timing today once I find a gun.what is your initial timing?
That doesn't mean to leave the vacuum advance disconnected permanently.This is the part that everyone questions
"Set spark timing at 32º before top dead center (BTDC) at 4000 RPM with the vacuum advance line to the distributor disconnected and plugged. This setting will produce 32º of total advance at wide open throttle (WOT). The HEI vacuum advance canister should remain disconnected. This engine is designed to operate using only the internal centrifugal advance to achieve the correct timing curve"
I have a local restoration shop with a dyno. Will give them a call tomorrow. Going to a car show tomorrow as well. Maybe I will run into someone with more knowledge than me. Shouldnt be a hard task...lol.The Hot Cam and Springs are a great upgrade....but you're not ready for that YET.
Instead, find a local dyno shop that still works on carbs and have your carb AND ignition tuned.
You have a real 350 HP V8 and 3.73 rears gears. You should be shredding tires at will off the line. Either your motor has a fatal injury....or your tune just sucks. Hopefully, it's the latter.
Just the cam and the LT4 valve springs. Funny thing was after the cam swap the 1405 Edelbrock was the best carb on that combo but seemed a little soggy on with the ZZ4 cam. On the ZZ4 cam, the 670 Holley seemed better, used it with the new cam but the Eddy would pull to 6500rpm and the Holley was not even close. I did not even try a set of 1.6 rockers and that's supposed to help the LT4 cam even more.You didnt change anything else? Literally just swapped cams?
"The HEI vacuum advance canister should remain disconnected. This engine is designed to operate using only the internal centrifugal advance to achieve the correct timing curve"That doesn't mean to leave the vacuum advance disconnected permanently...
You're right. I looked it up - GM did say to leave it disconnected."The HEI vacuum advance canister should remain disconnected. This engine is designed to operate using only the internal centrifugal advance to achieve the correct timing curve"
That is how I read it, seems pretty clear in their intent to me.