Hi. I am running a 68 327 in a 54 chevy pick up. I am suffering with flooding secondaries on the Holley 4150. Before I rebuild the carb, I have been advised to get a fuel regulator. Can you guys recommend one. I am looking but am getting so many results with a crazy variation in prices so I dont really know which to go for. I am in the UK so need a supplier that will ship or a make such as Holley that I can get over here. Thanks Jamie
We install quite a few fuel regulators on street driven cars and usually use this one. http://www.summitracing.com/parts/aei-13129?seid=srese1&gclid=CKijyqLa0cgCFRKRfgodH4IDfQ It is a bypass type regulator requiring a return line to the tank. Deadhead or inline types with no return are very poor at holding constant pressure under varying loads.
You won't need one with stock type pump & holley carb, they'll easily take over 7psi an dyour pump is under 6. You've got something else amiss.
I'm a bit confused . This regulator states 30-70 psi. Do I not need to regulate to no more than 7 psi?
Hi oj. Other members are telling me that any fluctuating pressure above 7 can cause fuel to bypass the O rings on the Holley.
http://www.summitracing.com/parts/aei-13129?seid=srese1&gclid=CKijyqLa0cgCFRKRfgodH4IDfQ That regulator is for EFI; not what you need. You need one adjustable between 4-10 PSI. In most cases they're not needed if the float valves in your carb are good. You did use a genuine Holley rebuild kit, right? The cheaper aftermarket Holley kits use a different style valve that is known for leaking, and worse yet can damage the bowl thread when installed.
Try putting a gage on it before spending a bunch of money. The fuel don't go thru or past the 'O' rings, the fuel goes thru a small hole in the middle called the seat. There is likely a small pieces of trash in there causing your problem. Pull the needle & seat out, spray them with carb cleaner, rattle them around so you can see how they work and reinstall them. You might be good to go.
Check the pressure. I have always just used a high quality mechanical pump. Easy to install and very dependable. Designed for carburators.
What others have said about you probably not needing one. But if you do need one or want one. I bought a malpassi filter king that is a glass bowl filter and a regulator. I had to have it sent to me from the uk.
OJ has it exactly right. Don't use one if at all possible. If you have, or are using an electric pump, there are many that pump 5-6 lbs consistantly. If mechanical, most stock pumps put out the same. To me, there are just too many bad stories about bad fuel regulators JMO
I run in tank pumps (tanksInc) in a couple of my muscle cars and another going in the 34 right now. I have to run bypass style regulators to both return constant fuel to the tank and dial down the pressure from the electric pump which delivers fuel injection pressures and would blow my little Stromberg's apart. You wouldn't need the bypass style for your application from what i read, Holley offers the same unit without bypass. I use the Holley 12-842 (I think that is the number), and I add a fuel pressure gauge directly to the unit to dial the pressure at the regulator which is always frame mounted near the firewall. They have never failed me (knock on wood). I can dial the pressure down to 4 pounds, if memory serves. If it helps.
First, let us know what fuel pump you're using. Kind of difficult to make a recommendation without all the facts. If it's a mechanical one, does it have two or three fittings?
I bought a couple of MALPASSI Filter King fuel pressure regulators on the auction site. I then ordered rebuild kits from England. I cant find the invoice but I think I found the source using Google.
As above "som ting wong" with carburetor. You have dirt in the needle / seat area or floats set too high or non OEM rebuild kit. Fix the carb before you "hypotenuse" your self!
I see good reviews for the malpassi filter king. It only regulates up to 5 psi though. Will that be enough for the Holley 4150 on a pretty mild 327 running stock mechanical pump?
The stock mechanical pump should only be putting as much pressure as the carb needs, you should not need a regulator. You might want to read the replies again, maybe you could answer some of the questions that we asked? then we could help you figure out what the problem is.
Hi Squirrel. Thanks for the input. This is my first american so I am still finding my feet with it. I would say the pump is standard. Just one inlet and one outlet Its funny how my previous question about my flooding secondaries had so many replies telling me to get a regulator on it, but this question about which regulator, gets so many replies telling me I shouldnt need one. It was like everyone seemed to be down on the Holleys on my previous question but when I asked what I should look to replace it with, all of a sudden Holleys are ok. Guess that we have all had different experiences. I havent done the rebuild of the Holley yet. Its pay day tomorrow so I will then be ordering stuff. I was going to get the genuine holley rebuild kit number 37-119 and after previous advice from those that know more than me, I was going to get a regulator and a second fuel filter. The truck was sitting for a while and I think she has just got a piece of muck in the carb. Perhaps I shall just go with the rebuild and the filter then and a see how she gets on.
You already have all the right answers awailable, just do it. Except one thing is missing, skip that and you have an never ending story in your hands. FLUSH the tank and replace the lines if it's been sitting for years, otherwise the crap just keeps coming and coming causing trouble with your needles. Filter as close to tank as possible. That expands the life of your pump too. So thats step one, then install the rebuild kit and tune floats, idle etc. as recommended. Stock setup does not need regulator. If you wish to add one for peace of mind, Holleys own cheapo works just fine. Then you'll need a quality pressure gauge after the regulator. Or just add that gauge now between pump and carb and verify the pressure is 5-6 psi. If not, then add regulator.
stock Gm style pumps only put out 5-6 psi and the holley can handle that easily the needle and seat or float are your problem ( seats dried out or gummed up with crud . float leaking or melted and not holding height ) , not the fuel pressure . if it was the fronts would be doing the same too . as its the same design . when you get above 7 psi ( 1/2 Bar) then you start having what we call creeping problems .
I have had stock replacement pumps that put out 8 and 9 pounds, way too much. Put a gauge on your setup, you might need to get a new pump.
Ahhh... The voices of reason and a logical approach. It can be a tough sell around here sometimes, but more power to you for trying!
If this has been an ongoing problem make sure you change the oil, unburned fuel in the oil is not good.
Thank you everyone. This site is a great source of experience and expertise. I have the Holley rebuild kit and another filter coming Monday. Thank you all for the input. Appreciate it.
Man I'll tell ya, Not knowing the fuel pressure and dicking around with a carb is about as silly as it gets.