Superblue87Formula

Well I got everything hooked up and tried to start the car and it was backfiring through the exhaust. I popped the carb off and turned it around 180 degrees and dropped it in and wired it up. Now I have it backfiring through the intake. What am I doing wrong??!

I figure I should probably rotate the engine to TDC and double check the rotor position, only.. how do you find TDC on and assembled engine??

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-=1987 Formula 350=-

Member Greater Cincinnati F-Body Association

Superblue87Formula

BTW: my setup is

-ZZ4 cam, performer rpm, holley 750 vac.
-Summit Distributor w/ internal coil
-Carter street pump (self regulating, pulling through stock pump)


I am getting fuel (fire pouring out of carb/exhaust..) and sparked (checked with timing light and I've been electrocuted a few times by it

Smasher

I had this exact same problem when I reassembled my engine after my cam swap.

From what you describe, your timing is WAY off.

Heres what you do to fix your problem:

Rotate the engine to where the #1 cylinder is on the compression stroke. To do this, pull the #1 spark plug and plug the hole with your finger. Disconnect the 12V source to your distributor(assuming HEI). Rotate the engine until you feel air escaping past your finger. If you're unsure, rotate it just a little more since the exhaust valve closing will push a little air as well as the intake valve. Once you're sure its on compression stroke, pull out your distributor and pop the cap off. Rotate the mechanism thingy(sorry forgot what its called) until it is just slightly counterclockwise of the 6 o'clock position(if you were looking at the engine standing directly in front of it). Drop the distributor back in but if it won't seat all the way down, don't force it. I had that problem, so I rotated the engine by hand just a hair and jiggled the distributor a little(make sure the rotor is still slightly left of 6 o'clock) and after doing this a couple times, the distributor seated all the way down. Once its in, reinstall your plug, hook up your distributor wires, and you should be able to fire it up. It'll probably run rough due to off timing, and if it dies, retard your timing a little and start it again. Once you get it to where it idles, you can set the proper timing and thats that.

HTH

sleeper

What Smasher is saying by the "6 o'clock" position is that the rotor should be pointing directly at the #1 spark plug wire/terminal when the cap is put back on the distributor.

When the backfire is through the carb then the ignition is firing too early... therfore you need to retard the timing by turning it clockwise.

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1986 Trans Am
carbed 350 - .30 over with 9.75:1 comp.
+- 315hp/390ft lbs.
700-R4 with 2500 stall
3.27 (ick!) gear
SLP 1 3/4" headers w/MAC catback and cat.
96 5 stars
SFC's, braces, arms, and a bunch more expensive stuff
no timeslips yet

Superblue87Formula

thanks guys, the dist was about 90* off (which is why going around 180 took me from too much retard to too much advance) I got it going after following smashers instructions. Thanks again.