Yay.. It runs.. But what timing should I set it to??

onefastmustang · #1 (**permalink**) 03-07-2009, 12:33 PM

So I got my car all back together and running.. I have it currently set at 6 BTDC per california law...

What should it really be set at for this cam???

CHANMADD · #2 (**permalink**) 03-07-2009, 03:31 PM

Which cam??

392cobra · #3 (**permalink**) 03-07-2009, 04:10 PM

I guess 34 TOTAL

Initial depends on how much centrifugal you have.

vettestr · #4 (**permalink**) 03-07-2009, 04:26 PM

We need more engine specifics to get you close. The old school rule says as much as she will take and then back the mechanical out so she does not exceed around 36 to 38 degrees total. I would guess mast hot cam, carb'd, pump gas engines will take 16 to 18 degrees initial at most.

onefastmustang · #5 (**permalink**) 03-07-2009, 04:51 PM

Here is the cam card... I just did like 25 miles and it runs awesome.. Sounds good too.. turned a few heads.. I think I will make a video...

Its a 351 stroked out to 392 (395 with the larger bore). Right now I am running a 4 barrel but will be putting my webers back on.

blykins · #6 (**permalink**) 03-07-2009, 05:03 PM

How much mechanical advance is in the distributor?

Also, to make a real logical guess, we need the compression ratio, how much quench you have, and what cylinder heads you're running.

On a a very efficient chamber, you usually don't need as much total advance.

eschaider · #7 (**permalink**) 03-07-2009, 06:08 PM

I generally turn the distributor around twice and lock it down. Occasionally its a little overkill but still pretty impressive!

Ahemmm.

The rest of the time I subtract the mechanical from 35 and use that number.

Ed

onefastmustang · #8 (**permalink**) 03-07-2009, 08:44 PM

I will have to dig into the mechanical advance tommorow.. too tired now..

But here is a quick clip...

http://www.youtube.com/watch?v=KMfzMIL6UTc

eschaider · #9 (**permalink**) 03-08-2009, 07:09 PM

Quote:

Originally Posted by onefastmustang

I will have to dig into the mechanical advance tommorow.. too tired now..

But here is a quick clip...

http://www.youtube.com/watch?v=KMfzMIL6UTc

Your car starts easily and sounds OK. If you have 6 degrees BTDC the engine will sound a lot more ferocious if you kick up the initial timing and add a little fuel. Suddenly you will start to get that thunder in the exhaust at idle that sounds so good.

You will also get more heat in the engine so be sure your cooling system is working right. If you don't have a high torque starter and the starter grunts when you start the car you might want to upgrade the starter.

Check for starter grunt after the car is up to running temperature and you shut it off. When it is hot and you try to restart it is when the starter will work hardest because it's hot too.

Good looking Cobra. You did a real nice job!

Enjoy.

Ed

onefastmustang · #10 (**permalink**) 03-10-2009, 08:35 PM

So based on all of the tips I have gotten from here and from Keith Craft I have done the following..

I have set my initial timing to 14 degreees. I have set my MSD distributor with the blue bushing, silver light and blue light spring. This should bring all of the advance in by 3000 RPM as recommended by Keith. However my timing light says it is stopping at 21 degrees or so by 3000 and not going any higher. Any thoughts on this?

wtm442 · #11 (**permalink**) 03-10-2009, 08:49 PM

14 initial. If there is any hard starting when engine is hot (and its not gas percolating), reduce the timing to 12 degrees (or upgrade starter as mentioned).

Fill tank with highest commercially avalable octane (93?)

Total advance - set at 36 degrees. Find a highway with a hill. In 4th or 5th gear at about 60 MPH, accelerate slowly and listen for any pinging. If there is any pinging, reduce the total advance to 34 degrees. Still have pinging - need higher octane gas or less advance.

When setting initial at 14, you might have some of the mechanical advance already into the dizzy. Reduce the idle RPM and see if the 14 degrees changes. 2100 RPM is a little low for all of the advance.