Help Carb Guys
 

Ok well i finally put the stang back on the road today and while its still cool out (0c) its nice to have it back out. But the carb is running like crap. Its not gummed up or anything it just needs to be tuned. Right now the motor is pretty much stock except i put on my performer rpm air gap intake, 625 road demon, headers exhaust, and a windage tray. Right now the car has 68's in the front and 76's in the back. The problem is if you are low in the rpms and mash the gas the car backfires and sputters until it gets up back about like 2500-3000rpm. Am i too lean? what do i need to do to get it running like it should be.

problem
 

Sounds like the accelerator pump. Maybe not getting enough gas into the motor when the throttle plates open.

I agree with oldschool. Try a bigger squirter nozzle, and make sure the accelerator pump is set up right. It should start squirting fuel in as soon as you move the throttle linkage. You may have to fool around with different accelerator pump cams and squirters (I'm assuming its like a Holley) until you find the right combination.

Does it improve when the car is warm?
I'm not sure if I believe this myself but I've heard talk about fuel puddling in the air gap manifolds in cold weather?

How is it just taking off from a stop sign and mashing the gas? What type of distributor are you using and what cam do you have? My thought is try more fuel by advancing the squirter cam but you will also need timing at full advance when you go WOT so by either locking advance out and setting up timing at full advance all the time you might learn something there to. Just food for thought. I had a Torker II intake on just a 302 with a B-Cam and 1.7 rockers and down low was a pooch but didnt have a bog. Had the squirter cams adjusted so they would be on as soon as you blip the throttle and had the base time at like 14 and the MSD dist setup with I think very weak springs so it would advance right away.

Brad

Well i talked to a local hot rod shop and they said it probably just needs to be tuned for the car. They also mentioned that since its below 0c right now, that intake isnt giving the carb any heat so it could be icing up a bit. So i put the dam back in my hood scoop and also gave the car a little more timing. We'll see what happens when i take it to them to tune.

The cure for the accel pump is to use the light blue holley pump cam in the first hole. Adjust the linkage accordingly.

I did it and it cured all but my rich idle problem with my Demon.

Ahh, that's probably it. That's why most of us other Canadians stuck with the standard RPM intake (Best Buy talked me out of spending the extra $90 when I told them that I might drive it in the cold).

My mustang doesnt see much winter at all. Just this last trailing end because i wanted to drive it too much. And before it had alot more of the combo to match it.

I know, I do less cold weather driving than I though. I parked it at the end of October and don't plan on bringing it out until the roads are all swept. I doubt that the Air gap would've netted me any more power anyways.