ok so far everyone has helped us out and want to say thank you.so here is the next ? on the 396 402 1970 i have a hei dist. i just put in and set it up how the book said to .NO GO .got it to run but every time i bring the timing mark near were it needs to read it runs worse .the cap does not have a number one mark on it so i am playing guessing games with it how would any of you start fresh as if the engine was turned after dist .was out .thanks al

Albert,if your trying to set the timing to factory stock spec when using an aftermarket perf cam of any kind that can be the problem your having.

Stock factory timing is approx 0-4-6 deg btdc (depneding on motor/cam)and most aftermarket perf cams like 18 deg btdc base timing (3x-4x factory timing spec)for a good starting place for dialing in the timing.

So set it to 18 deg with motor idling low to ensure mech adv in dist isnt partially activated upsetting the base when setting it.

Due to perf cam requiring a lot more base timing then you need to have the mech in the hei dist recurved for approx 18 deg all in by 2800-3k rpm.

Then 18 btdc base + 18 mech =36 deg btd total which a good starting place,setup may even respond well to & tollerat 38 deg total but watch out /listen for detonation.

For street use you should also run a vac adv thats full activated at idle hooked to full vacuum all the time for even better idle & fuel economy with perf cam.

But if there is a bone stock gm cam in your motor and its running bad when setting timing to spec something else is wron like bad/inaccurate timing light,slipped outter ring on ballancer,using worng plug wire for checking/setting timing(use #1/1st cyl 2 front of motor on driver side),timing chain is off a toothe or has slipped a tooth due to being streeched,etc.

Scott

Scott

You sure the timing tab hasn't been changed?
http://macc.chevelles.net/images/dist1.jpg

thank you this will come in handy

thank you will try to set it up and lt you no thanks again al