Fuel system woes....

[bohn]

Ok..i have a brand new holley blue pump, less than a month old and regulator that came with it on my truck. I'm running 6psi of fuel pressure. Evertime i go to do a burnout it will die as soon as i hit the brakes to slow down, then take along time to fire back up. Anybody at the track witnessed that last night.

At wide open throttle it will act like it runs out of gas about 5 second into the run, like it sucks the float bowls dry , then after a few seconds comes back to life. goes like bat out hell then dies again. If i'm mellow with it it runs fine. I pulled the carb off this morning and took it apart and all looks good. But the carb gasket between the intake and carb is soaked like its getting to much fuel pressure. Which leads me to believe that the fuel pressure regulator is spiking and feeding to much fuel. But the engine dieing at WOT leads to believe that theres not enough fuel pressure.

I'm kinda lost here because eveything is new, and i have two fuel filters and both look clean. One thing that bothers me is that if i turn the key on and run the fuel pump, without running the engine the regulator makes some terrible noises. But the one i had before this one did the same thing, so i thought it was normal.

I'm lost anybody have any advice??

[Blue69]

My guess would be that it dies when you hit the brakes because fuel is sloshing out the vent tubes and flooding the engine. You can extend the vent tubes with a length of fuel line connecting the two vent tubes, just cut a notch in the topmost part of the line to vent carb bowls.

The other problem could be the rear jets getting uncovered as you accelerate and fuel tries to crawl up the rear of the back float bowl. First check to see if float level is set high enough, if it is then you might try a set of jet extention tubes, to keep the jet opening in the fuel.

[jdsgallops]

What fuel bowls are you running?

[1SLO5.0]

More importantly what kind of carb?

[bohn]

Its a holley 3310, yesterday was the first day i ever had it apart. Thing is that i have had this system on there for the last month and have put maybe 200 hard driven miles on it and its never done that. This was the first time it ever acted like that. I thought maybe it was vapor locking, but on the last run i let it cool down to 110 degrees and that was the worst run yet.

[jdsgallops]

More importantly what kind of carb?

No Darrell the bowls are more important. I had the exact same problem Dan is describing on my 600 vacuum secondary holley equiped 302. The 600 vac sec. uses side hung bowls. The side hung bowl is smaller than the cathederal bowl of the bigger holleys. Once I switched to a 750(3310) on the 302 I didn't have the starting line bog anymore(thus if I put the bigger bowls on the 600 I wouldn't have had the problem). Talking with a Chicago based super stock racer I found out this is a common problem. The fuel pump can't keep up so the bowl empties on the burnout and doesn't fill back up in time for the launch. The car bogs, falls on it's face, and then takes off like a raped ape. At that time I was only running a Holley Red.

With a Holley Blue it *should* be keeping up. Thus I would look at two different things.

1-The regulator. The regulator that comes with the Holley Blue's is a known POS. Replace it with a good quality unit. This is why I am actually a fan of the Mallroy Comp 140 Pump. Puts out more GPH as the Holley blue(actually same as the Holley black) but comes with a good regulator for not a whole lot more money.

2-Check your electrical connections. If the pump isn't recieving a full 12 volts then it isn't going to pump the factory rated GPH. It could be as simple as the wire powering the pump not being large enough in diameter causing voltage to drop by the time it reaches the pump. I would basicly look over that whole wiring for the pump system including output of the alternator at idle to make sure it is powerful enough to maintain proper voltage to the pump.

[Jim]

hmm. maybe it's not the carb. what plugs are you running? i would pick yav8's brain too.

were you running slicks? is it falling on it's face at the line or later down track?

[bohn]

hmm. maybe it's not the carb. what plugs are you running? i would pick yav8's brain too.

were you running slicks? is it falling on it's face at the line or later down track?

I had a set of drag radials on it, and yes it had a bog off the line, my best 60ft was 2.06 and i don't think it was spinning, just laying over. It would run from the 60ft great to the 8th mile then die out again then fire back up. I do recall the volts fluctuating right before ever pass but not much maybe 2 volts max, which i though was kind strange. and that it never did before either. I'm gonna get an aremotive regulator this week and check the wiring of the pump and see if anything is wrong.

Plugs are AC/Delco R44's they look ok, but alittle balcker than normal.

[Jim]

your converter may be a tad tight too if it's off the line, or you may need some jet extensions, or bigger squirters.

[1SLO5.0]

your converter may be a tad tight too if it's off the line, or you may need some jet extensions, or bigger squirters.


or gearing or improper cam selection......etc

[bohn]

I don't think anythings wrong with the combo, just something i'm over looking with the fuel system. Like i said it ran fine the other times i've taken it out, and i always beat on it, just to make sure nothing like this happens at the track. Hopefully that regulator will solve the problem.

Thanks for the advice guys.

[STL2SLO]

If the voltage is fluctuating and then it bogs I think you found at least part of your problem. Try to fix the electrical first.

[Kevin Garceau]

First that whole fuel system is trash... holley blues are pos that can die at any given time. As said their regulators are junk too.

The dieing when you hit the brakes IS fuel sloshing out of the vents.

the bog off the line could be anything, but I will bet you a beer it has nothing to do with rear jet extensions. It is NOT leaving hard enough to make that big a difference. My firebird ran 1.30 sixtys on the back tires, and didnt need jet extensions.

It dieing on the later part of the track is making me think you could be running out of fuel in the bowls, restriction somewhere, or loss of voltage. But your car doesnt seem to be running big enough motor where it is running out of fuel.

[bohn]

Well i took it for a drive again tonight, stopped did a big burnout and it died again. Took it up to 6500rpm in second, and it died completely. Costed to a hault and for about 20 minutes would not start, did some investagating and found that my power wire for the distributor fell out !!!! Pluged it back in and its real loose in there and will fall back out just by touching it. I wonder if this is my whole problem, maybe the force of stopping and accelerating is causing this wire to loose its contact. Ummm...i'm gonna put a new end on it this weekend and hopefully that will solve my problem.

[Joel_91GT]

did some investagating and found that my power wire for the distributor fell out !!!! Pluged it back in and its real loose in there and will fall back out just by touching it.

it might not be the whole problem but im sure its not helping matters at all!

[Randy Schonscheck]

It may sound weird, but make sure your tank is vented enough. It's kind of like when you pour gas into your car and not have the little "breather" hole open on the gas can. There is usually a small hole in the gas cap which can become plugged. Something simple to check. Good Luck!

[Randy Schonscheck]

Is the Chicago based S/S team Alex and Tony????? A great father / son team with a take no prisoners approach to racing their Fords. Lots of years of experience, so they have probably seen just about anything that can go wrong. Could be why they hold a "couple" of records. :rockon1: :applaus:

[UPdragracer]

sounds like a combination of problems , float level too high and not enough fuel flow under WOT . JMHO. I did notice your truck looked rich when it was running bad at the 1/8th mile . {like an ignition problem}

[Kevin Garceau]

"Is the Chicago based S/S team Alex and Tony????? A great father / son team with a take no prisoners approach to racing their Fords. Lots of years of experience, so they have probably seen just about anything that can go wrong. Could be why they hold a "couple" of records."

I dont think Denyesenko's are out of Chi-town... yes set lots of records with the 289 powered "money maker" mustang. Son is driving a capri now, they have been class racing in IHRA the past few years, on the division circuit with myself. Nice people, dont know them very well though

[Randy Schonscheck]

Hi Kevin! Alex and Tony live in Lyons, which is a suburb of the Windy City. Alex drove Tony's car at the Indy Div opener a couple of weeks ago. Tony is still nursing a very painful back that happened when some SOB ran a redlight and hit him broadside. This was last fall and is still giving him problems.

[jdsgallops]

Is the Chicago based S/S team Alex and Tony????? A great father / son team with a take no prisoners approach to racing their Fords. Lots of years of experience, so they have probably seen just about anything that can go wrong. Could be why they hold a "couple" of records. :rockon1: :applaus:

Yep sure is.