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fuel boiling solutions

I’ve used to plumb it to a regulator, but have heard that one of these 3 port fuel filters is being used with success by some.

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The problem I had with those is that takes the pressure down too far. I went to a 9 psi pump, Holley regulator, and 1/4” return line. Keeps pressure at 6.5 and still circulates the hot fuel back to the tank.
 
I had the same problem of boiling the fuel out of the Holley 850 DP on a 440. I tried insulating the lines and filter and already had a 1" phenolic spacer. I was told a return line would eliminate the problem. I wasn't sure it would. I bought a Mopar vapor separator and am adding to the mechanical pump. I have 3" headers and ported 915 heads. I was not sure all of this would solve the boiling problem. I drove home from a 15 mile run on a 90*+ day, shut the engine down and lifted the hood and shot the temp with a gun. Carb was 205*, headers were 320. I let the hood open for 2 min and then shot the carb and headers. Carb 160ish and headers 305ish. Closed the hood and waited 5 minutes. Opened hood and shot carb and headers. Carb 190* and headers 280ish. (I didn't write the exact number down, didn't need to) The whole problem for me was the residual head coming from the headers. In order solve the problem I went to two electric fans with two relays and a Daytona Digital Controller that will not only supply the needed air through the radiator, but will continue to "exhaust and cool" the engine compartment for up to 5 minutes. In my case, problem solved and backed up with the vapor separator.
 
I had the same problem of boiling the fuel out of the Holley 850 DP on a 440. I tried insulating the lines and filter and already had a 1" phenolic spacer. I was told a return line would eliminate the problem. I wasn't sure it would. I bought a Mopar vapor separator and am adding to the mechanical pump. I have 3" headers and ported 915 heads. I was not sure all of this would solve the boiling problem. I drove home from a 15 mile run on a 90*+ day, shut the engine down and lifted the hood and shot the temp with a gun. Carb was 205*, headers were 320. I let the hood open for 2 min and then shot the carb and headers. Carb 160ish and headers 305ish. Closed the hood and waited 5 minutes. Opened hood and shot carb and headers. Carb 190* and headers 280ish. (I didn't write the exact number down, didn't need to) The whole problem for me was the residual head coming from the headers. In order solve the problem I went to two electric fans with two relays and a Daytona Digital Controller that will not only supply the needed air through the radiator, but will continue to "exhaust and cool" the engine compartment for up to 5 minutes. In my case, problem solved and backed up with the vapor separator.
That’s a great solution. I have non ceramic headers too.
 
Also cool collection of mopars...

Excellent video. I didn’t know there were 2 types of 3 port fuel filters. I wonder how to decide which to use? Maybe try both to make sure no restriction of carb supply fuel pressure?

I also wonder if a heat shield wrap around the mechanical fuel pump is worth doing?
 
Excellent video. I didn’t know there were 2 types of 3 port fuel filters. I wonder how to decide which to use? Maybe try both to make sure no restriction of carb supply fuel pressure?

I also wonder if a heat shield wrap around the mechanical fuel pump is worth doing?
The problem itself is the modern gasoline, it boils, the modern cars with FI don't have that problem because of the high pressure the injectors require, the fuel line is pressurized the hole time, beside isolate the pump is no help because the heat itself is in the carb, in so many words, carbs with modern gas are doomed.
 
The problem itself is the modern gasoline, it boils, the modern cars with FI don't have that problem because of the high pressure the injectors require, the fuel line is pressurized the hole time, beside isolate the pump is no help because the heat itself is in the carb, in so many words, carbs with modern gas are doomed.
But if you watch the video he says that the fuel boils in the carb AND the pump. So even if you shield the carb, it could still boil in the pump. With the 3 port fuel filter keeping fuel moving through the return line, maybe it’s a moot point.

I used to have my return line hooked up but last year when doing some fuel line wrap and re-route work, a knowledgeable mechanic convinced me to disconnect it, saying that with carbs it’s no use. I shouldn’t have listened to him. If I remember correctly, I left the line in place but just disconnected and shortened it on the engine side. May need to rig it back up. I haven’t tested the car under heat soak conditions yet this year.
 
Also cool collection of mopars...

That was interesting, thanks for posting it. I think I will try one of those WIX filters with an orifice on my current project.
 
Here is another good one to watch

 
But if you watch the video he says that the fuel boils in the carb AND the pump. So even if you shield the carb, it could still boil in the pump. With the 3 port fuel filter keeping fuel moving through the return line, maybe it’s a moot point.

I used to have my return line hooked up but last year when doing some fuel line wrap and re-route work, a knowledgeable mechanic convinced me to disconnect it, saying that with carbs it’s no use. I shouldn’t have listened to him. If I remember correctly, I left the line in place but just disconnected and shortened it on the engine side. May need to rig it back up. I haven’t tested the car under heat soak conditions yet this year.
A mechanical pump is connected to the block, the block is hot, just for the fun buy an cheap electric fuel pump ( with the solely purpose of test this idea) connected away from the block and the new fuel filter and try it, that's what I would do.:thumbsup:
 
FYI-My video I posted is a option. I'm considering it but I saw Mopar fuel vapor seperators on line fairly on the cheap side. I migh plumb in one of those.
 
Anyone have a part # for the 3 port style orifice and non-orifice in line fuel filters? I can’t seem to find one on summit.
 
I found an old FBBO 2012 thread on this. If you want the filter with the vapor return line coming off at a 90 degree it’s Wix 33054 (5/16”). Not sure for 3/8”. Install between pump and carb with the vapor port facing up is what the thread recommends.

My 2 port in line filter is between tank and carter mechanical pump on passenger side and never had a problem. Doesn’t look like much room to install between pump and carb without it living in front of tbt air cleaner...
https://www.forbbodiesonly.com/moparforum/threads/what-is-this.39825/
 
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