Should I change timming?

bullhded01 · 10-08-2008, 06:35 AM

After changing from a 2bbl smog comliant carb and intake on my 302, to a 4bbl edlbrock and wiend intake without smog crap should I change the timming from the 8 degrees that was stock, and to what? Also, my vacume advanced is running off of the drivers side port (constent draw/normal draw) off the carb, and if I put it to the pass. side (timed port) it backfires up through the carb. Is this a timming issue, or a carb issue?

mark v · 10-08-2008, 08:06 AM

Leave at stock and adjust as necessary.

cjones · 10-09-2008, 01:47 AM

the vacuum hose should only have vacuum during load (venturi vacuum). should have NO vacuum at idle.

set timing at 8* BTDC with vacuum hose disconnected and hose plugged.

you should also adjust the carb per instructions if you haven't done that already.
after setting timing and putting vacuum hose on correct port. you can bump the timing up in 2 degree increments and test drive car to make sure there is no detonation (pinging). if you are running 87 octane gas then 8* maybe 10* would be max, most carbed mustangs are 10*.

bullhded01 · 10-12-2008, 07:19 AM

Thanks guys, I already had it set up at 8* and the truck was running o.k. I just wasn't sure if I could maybee get a little more out of it, and also making sure it wasn't just plain wrong at stock settings with new bolt on stuff. Although I did have the vac advance on the wrong port. Thanks again.