[ma67cpe]

I have a 67 mustang with a slightly modded 302. The motor has an autolite 4100 carb with a crower 15202 cam, edelebrock performer intake and its bored 40 over. I was having a problem with vacuum so (baron) moved my vacuum from the carb to a port on the intake. Now Im getting advance but when I put it "in time" it boggs in low nd runs great in high. If I advance the timing it runs great in low and pops,backfires exc in high. I havent tried retarding the timing to much cause I was afraid that the lows would get worse. any body have any ideas or free time this weekend? thanks in advance. Here are pictures of my plugs.

[S-Car-Go]

Get your timing sorted out. Start by disconnecting the vacuum advance and plugging the carb side. You don't need it at this point. V/A is for just mileage. Figure out where TDC is. Pull the valve cover over #1 and confirm both valves are closed when the balancer says TDC. Maybe the pointer is off. You will chase your tail until you get it timed right. Maybe the distributor is out 180* and your timing is so wacked it runs. I've seen this happen.

[ma67cpe]

Originally Posted by S-Car-Go Get your timing sorted out. Start by disconnecting the vacuum advance and plugging the carb side. You don't need it at this point. V/A is for just mileage. Figure out where TDC is. Pull the valve cover over #1 and confirm both valves are closed when the balancer says TDC. Maybe the pointer is off. You will chase your tail until you get it timed right. Maybe the distributor is out 180* and your timing is so wacked it runs. I've seen this happen.

Ok I will start there. thanks for the advice.

[RebelTide]

Once you follow the TDC instructions given to you by "the snail" correctly, line your timing mark up for 9 degrees initial advance. This should be a good starting point for the cam you have. Whatever you do, get a new set of plugs. Street cars do well with the old BF42's. If you want to play dragracer, you can drop down to the BF32's. I don't know the current Autolite numbers for those plugs. My age is showing. Good luck.