Chevy Nova Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter #1
I installed a Summit HEI distributor with a multi-spark CDI Ignition and rev limiter box and can not get the thing to work right. My motor idles fine, runs rough from 3,000 rpm, and backfires on deceleration. The thing ran beautifully the day before I installed it.

I installed it according to Summit's instructions, and even caled their tech support people to clarify my understanding of the instructions. I taped the un-used trigger wire, twisted the pair of wires that go to the distributor trigger, connected the power directly to the battery.....ugh I hate electronics.

Any ideas?
 

·
Premium Member
Joined
·
630 Posts
Check to make sure the rev limiter is not set to low and that you have 12 volts at the coil.
Check your base timing and your total timing. Just stuff I would check......:)
 

·
Registered
Joined
·
1,474 Posts
Double check your connections to the pickup coil ; you may have the polarity backwards..... screws up the timing.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #4
Yea, I'm baffled. I have 12 volts at the coil. Timing is right where it was before I changed the coil but it feels like it is a little more advanced initially because it is kind of hard to crank.

Tell me though, would it run at all if I had the wires to the pickup coil reversed? The wires are green and violet (according to the directions) and I'm color blind. They look right but I can never be sure with color coded wires. I know I have the wires to the coil right because they are labeled and I spliced them to re-use the original connector to make sure they don't arc or anything.
 

·
Registered
Joined
·
1,474 Posts
Yea, I'm baffled. I have 12 volts at the coil. Timing is right where it was before I changed the coil but it feels like it is a little more advanced initially because it is kind of hard to crank.

Tell me though, would it run at all if I had the wires to the pickup coil reversed? The wires are green and violet (according to the directions) and I'm color blind. They look right but I can never be sure with color coded wires. I know I have the wires to the coil right because they are labeled and I spliced them to re-use the original connector to make sure they don't arc or anything.
Yes it will run if the pickup polarity is wrong. The correct polarity is whatever way shows the timing being the most retarded. Make note of your intitial timing as it is now then reverse the leads and check it again.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #6
Thanks Shawn. I'll check it when I get home.

I put a timing light on it after I installed the box. I know I did not move the distributor because the hold-down is so tight I can't move it unless I loosen it. I thought I was smoking crack because I had 14 degrees initial and 36 degrees total in it before I installed the box and afterward I had 12 and 32 respectively. The problem is that is the reverse of what you would expect if the correct connection would be the most retarded because installing the box seems to have retarded the timing. Right? Or does that mean it was wrong before and it is right now?

Maybe the short answer is to just be quiet, reverse the wires and see if it runs right and forget about why... Thanks again. I'll let you know.
 

·
Registered
Joined
·
4,612 Posts
i'd ,,

i'd take an inductive timing light , and move it to every spark plug wire and watch it to see if the cylinders are firing consistantly. You might have a plug trying to foul or has fouled ,, if its backfiring on de-acceleration.
 
1 - 7 of 7 Posts
Top