88_Import_Slaye

Ok, so I get the car in a drivable state today. I fire it up, put it in reverse and it goes. I put it in drive, and it almost goes, I put it in 3rd and I get going. Now, I back up again, then try to pull away to go for a spin around the parking lot and when I shift into drive, it starts to die, then dies.

We killed the battery when we tried to get it back up again, so we got a brand new replacement. I put it in, but it STILL wont turn back on.

After 20 min in the freezing cold, we find that the fuel pressure is at 10 psi!! I set it to 5-6 psi when I got it and it decreased itself once before. I set it back to 5-6 psi, and try again, but it just wont start. we pull a plug and it's soaked in gas and pitch black.

My questions are

1. Why is my mallory 4 port regulator increasing fuel pressure? I have a vacuum port on it that isnt sealed, or going to anything. No cap on it, just open. should this be closed off or go to something?

2. How do I adjust my Edelbrock 1406 (performer) carb to not run so rich. I have the two screws in the front. The book that came with the carb doesnt really give me much to go on, except for some charts.

The plugs still fire, when dry. We pulled one, wiped it off and test fired the engine, the plug got spark, so the afr isnt too big of a deal yet. I dont have an AFR gauge to tell what it's at, but when I fire up the motor cold, it has some smoke. My friend says it's blue and could be from burning oil. I'm hoping he's wrong and it's just because it's so rich. I was grey outside today, very cold (-10 c) so maybe the smoke appeared blue.

12SecondTA

I have that regulator and have never experienced it increasing pressure. Are you sure your guage is correct?

The vacuum port i dont have connected either, and never will, its really for boost applications.

The fact that your plugs are soaked and you think your pressure is high just tells me your pressure was way too high to begin with. The pressure you ran obviosly was way too much for the edelbrock. Readjust pressure to 4psi. 4psi is plenty to get the car running. Then get the car running and drive home, get an Air/Fuel guage at your local autozone, they sell them for like $40, and use your stock O2 sensor with it. I'll almost guarentee your edelbrock was blowing out gas into the exhaust. I've been there and done that, I even have pictures of the fire.

12SecondTA

general rule of thumb always run as lean as possible on idle, you dont want to foul your plugs waiting at a light. Screw your adjustment screws in all the way and take 2 full turns out, thats stock adjustment. Dont adjust from there until you have an air fuel gauge and know what your doing.

AFR is always a big deal, quality of idle is the most important thing.


black smoke is fuel, grey can be a mixture. So no big worries.

88_Import_Slaye

I was told for my 1406, 6 psi max before the carb gets flooded, I had it set to 5, it would go between 4-6. The gauge is connected to a port on the regulator with 6 inches of hose. The gauge is from summit. Brand new.

I dont have any "stock" anything. The car was gutted 100%. I have stock rear end, that is it. I dont have exhaust. Only headers. No O2, no smog crap.

The car is not yet drivable, well, it is, but this problem caused us to not be able to drive it.

I'll drop the pressure down to 4. But why does it increase/decrease on it's own? There is obviously a problem. any ideas what it could be? Only thing I can think of is that vacuum port just needs a cap.

Edit: BTW: When I originally set the regulator, after motor break in, we checked the plugs, they were PERFECT. The regulator going to 10 PSI is why the plugs where soaked, not because it was too high to start. I checked the gauge the other day while installing p/s pump and it was correct 4-6 psi.

So something caused the reg to jump to 10psi. The nut was tight, i checked.

88_Import_Slaye

thought, maybe there was some crap that came out of my tank and got clogged in the regulator, that is why it dropped PSI, when I "adjusted" it again to get back to 5 psi, i set it too high and just today the clog was removed and so the flow increased. That would make sense.

12SecondTA

i doubt it. I have the exact regulator and am in the same boat as you. MY car is 100% gutted, and seems to never be like it used to be before i started tinkering.

I dont care if your plugs were white after cam breaking, cam breaking always runs leaner buddy. PLus cam breakin is at a level where your idle air screws dont do anything.

Idle ratio is what we are currently talking about.

MY first though is that your return line was comprimized. If you dont have a fuel filter i feel sorry for you. There should be a fuel filter before your regulator for just these incidences. That regulator wont like particles of crap near it. If you dont have one, go get one.

I still say your carb is at fault.

Dont add to the list of complaints about these regulators. 98% of all problems i've read can be linked to user installation malfunction.

88_Import_Slaye

no offense, but you dont have to talk to me like i'm an idi0t. I'm not complaining about my regulator. I love it, that is why I bought it man. I'm simply asking what the cause might be. however, how is the carb at fault if the regulator jumped the PSI to 10 and the carb only handles 6 max? It isnt, it would be my fault for turning it up. I have a filter between the regulator and the carb. I have a filter to go between the tank and reg, but have not put it on yet due to the fact i'm still putting things to gether and the fuel lines are not 100%.

The carb has not changed since i took it brand new from the box. I will do the adjustment as you stated, hopefully that helps. But, I still maintain that it was crap from the tank and it just finally broke loose today. Either way, what do I do with the vacuum port? do I leave it un capped, or cap it?

12SecondTA

i'm not trying to make it seem as if you are an idiot. thats not my intension. Its just always the simple things, or the thing you previously ruled out.

Not too long ago a kid around the corner bought one of those new holley carbs, its a 600cfm one. Its not adjustable in anyway. if that helps you know which one it is. Wel he calls me one day saying he installed his new carb and the car runs great. Said he;d call me back after the test run. Called me back 15 minutes later, guess what? The car stopped and fuel was squirting out the bowl vents and all kinds of stuff. YOu might think that the regulator was at fault right? I told him not to touch a thing until i got there. Meanwhile the kid is calling people trying to get opinions of what happened. PEople are saying the regulator, the same mallory one we have, is the problem, that the pressure/flow rates are way too high. I wish i could slap them all.

When i got there the motor was already hydro locked. Anyone around here already figured out the problem?

Well he had pressure so high from the start that when he gave the car some gas the bowl emptied, and well, the pressure push the needle out of its seat. The needle was actually raddling around in the bowl. Too much pressure will cause carb problems in an instant. This is my point!

88_Import_Slaye

wow, didnt know that it could damage the carb. Dont want to fix it, it's only few months old. Well, I'll drop it down to 4 psi and watch it. Once I get my final fuel line setup, i'll put in the filter. Thanks for the carb adjustment tip. I'll be getting an AFR reading once I get exhaust on it. It wont see any road time until I get exhaust