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fuel boiling solutions

Why didn’t I think of that earlier:) I just did that test and blowing into either inlet or outlet flows freely. Blowing into the outlet side didn’t feel any more difficult but maybe a slight less amount of air velocity existing the inlet port. I don’t think it will be an issue. I will see if Wix confirms.
Keep an update
 
UPDATE... I put in the MOPAR vapor canister (confirmed .060" opening on return) with a 1/4" return line to the tank. I am running a mechanical pump on a 440. My fuel pressure used to be 6.5, maybe closer to 6 at idle. Now, I have the pressure gauge jumping all over the place between 4.5 and a little over 6 psi. AT IDLE. As soon as I rev the engine, the gauge settles down to about 5.75. I took the car out for a short run and observed no problem with starvation or power, but I think I am going to consider an electric pump with regulator and return. My 440 puts out about 500 hp and I think I would like that extra safety margin with it comes to fuel pressure. I might add, that I do not just rely on the fuel canister to solve the boiling issue. Recall, I have large headers that run about 325*, or better. The engine compartment on a 90* day cannot get rid of the heat soak from the headers. I went ahead and put one two electric fans with dual relays and a controller that will allow me to set the two fans to come on and go off at any level I chose. More important to solving the temp issue in the compartment, when you turn the engine off, the fans will run anywhere from .5 to 5 minutes. This should be enough time to exhaust the hot air coming from the engine and primarily the headers. I also put a air temp gauge along with Dakota water temp gauge so I can monitor what is happening with respect to air temp at the carb. I will do more evaluations and provide temps and timing in a later post.
Oh, one other thing, on the return line to the tank...i elected to go with a Moroso EFI return adapter that goes on the fuel filler tube. Did not want to cut a hole in tank or sender unit. Seems to work great, especially with so little gas being returned. Should work with an electric pump as well.
 
Sputnick- can you post specifics about the canister, like where did you get it. You did confirm a .060" opening? The Moroso EFi adaptor you talk about. I'm going to be on the road with my car soon as I get home to do a few things to mine but mainly getting home from my deployment. If I can't be worry free with the boiling/soaking of my fuel (with a mechanical pump) issues that I might have to deal with, then I'm gonna lean torwards a complete EFI system. This is on my '71 RR and my engine was dyno'd at 600 HP
Thanks
 
Sputnick- can you post specifics about the canister, like where did you get it. You did confirm a .060" opening? The Moroso EFi adaptor you talk about. I'm going to be on the road with my car soon as I get home to do a few things to mine but mainly getting home from my deployment. If I can't be worry free with the boiling/soaking of my fuel (with a mechanical pump) issues that I might have to deal with, then I'm gonna lean torwards a complete EFI system. This is on my '71 RR and my engine was dyno'd at 600 HP
Thanks
Go back to page 4 and you will see the specifics on the canister. Mine came from Yearone. The Moroso EFI adaptor can be bought at Summit and Classic Ind. EFI will solve the vapor lock. I have both an 850 DP on a 440 and a FAST efi on a 383. I keep swearing I'm going to go back to carbs on the 383. However, it is nice to jump into the car in cold or hot weather and a quick turn of the key......Brroooooommm. If you are going the efi route, consider the 3x2s. Welcome home.
 
Thanks Sputnick
 
I am in the future stroker motor going Holley Sniper EFI ...
But for now I am facing the same things as you guys so after I burn up for electric fuel pumps and still had vapor lock issues I did away with my braided fuel line from Midway under the car and I ran 3/8 arrow aqp socketless hose that came from summit and to keep it away from heat I rent it through the frame of the car from behind where the transmission cross brace goes in up through the frame rails out in front of the engine bay and back to a mechanical Carter Street strip fuel pump what's my fuel pressures like 5 and 1/2 which is crazy I like to have about six and a half to seven and ran the same hoes up to my carburetor but I'm still facing vapor lock issues so I'm going to go ahead and put me on one of those fuel filters that has a vapor return line which I've shared with you in these pictures it replaces the fram in the wick one I got it from AutoZone very inexpensive seems to be very well made and I'll know by this weekend whether or not it works.
I do have the wix filter or it would be the Napa brand basically the same thing but I chose to use the AutoZone one because in my opinion the ease-of-use with the return line extension coming out the side and I'm just going to run it back to my fuel tank return side with some quarter inch rubber fuel line for now and see how it does I hope it fixes the problem because I am frustrated.

IMG_20190909_181316705.jpg IMG_20190909_181340860.jpg IMG_20190909_181355191.jpg
 
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I am in the future stroker motor going Holley Sniper EFI ...
But for now I am facing the same things as you guys so after I burn up for electric fuel pumps and still had vapor lock issues I did away with my braided fuel line from Midway under the car and I ran 3/8 arrow aqp socketless hose that came from summit and to keep it away from heat I rent it through the frame of the car from behind where the transmission cross brace goes in up through the frame rails out in front of the engine bay and back to a mechanical Carter Street strip fuel pump what's my fuel pressures like 5 and 1/2 which is crazy I like to have about six and a half to seven and ran the same hoes up to my carburetor but I'm still facing vapor lock issues so I'm going to go ahead and put me on one of those fuel filters that has a vapor return line which I've shared with you in these pictures it replaces the fram in the wick one I got it from AutoZone very inexpensive seems to be very well made and I'll know by this weekend whether or not it works.
I do have the wix filter or it would be the Napa brand basically the same thing but I chose to use the AutoZone one because in my opinion the ease-of-use with the return line extension coming out the side and I'm just going to run it back to my fuel tank return side with some quarter inch rubber fuel line for now and see how it does I hope it fixes the problem because I am frustrated.

View attachment 831983 View attachment 831984 View attachment 831985
Nice! I have a WIX filter with the 90 like that, but haven't installed it yet. Is the Fram filter you show above a 3/8" or 5/16" for the inlet/outlet? Also, before you install it, look inside the 1/4" 90-degree side port and see if it looks like a small orifice. If you can measure it with a pin gauge, all the better. It should be about 0.060" inner diameter. If the 90-degree small ID hole orifice is too big, you'll have fuel pressure supply issues.
 
Nice! I have a WIX filter with the 90 like that, but haven't installed it yet. Is the Fram filter you show above a 3/8" or 5/16" for the inlet/outlet? Also, before you install it, look inside the 1/4" 90-degree side port and see if it looks like a small orifice. If you can measure it with a pin gauge, all the better. It should be about 0.060" inner diameter. If the 90-degree small ID hole orifice is too big, you'll have fuel pressure supply issues.
Awesome I didn't know that thanks for sharing I'll definitely check that out tomorrow when I get home calling it quits for the night and hang out with my wife I do appreciate all the information because it's very frustrating you want to drive your car and enjoy it and that crappy gas I got nowadays and I have the same boiling point as the old gas and it's basically they left behind the carburetor guys and just cater to the fuel injection cars that's why the future when I build my stroker motor I'm going to go fuel injection it just makes more sense at least to me
 
Nice! I have a WIX filter with the 90 like that, but haven't installed it yet. Is the Fram filter you show above a 3/8" or 5/16" for the inlet/outlet? Also, before you install it, look inside the 1/4" 90-degree side port and see if it looks like a small orifice. If you can measure it with a pin gauge, all the better. It should be about 0.060" inner diameter. If the 90-degree small ID hole orifice is too big, you'll have fuel pressure supply issues.
To answer your question sir the inlet and outlet on the fuel line yes 3/8 and the return is a 5/16 and it was a duralast fuel filter from AutoZone part number f f 34 21 DL
 
To answer your question sir the inlet and outlet on the fuel line yes 3/8 and the return is a 5/16 and it was a duralast fuel filter from AutoZone part number f f 34 21 DL
Here's a picture of both of the boxes I have with the fuel filters with the return line I don't have a pin gauge but I did take a paperclip and it fit down both of them so I hope that's a good parameter or a good guide to go by one is a duralast from AutoZone the other one is a Napa brand what you can see in the pictures

IMG_20190909_191849749.jpg IMG_20190909_191841671.jpg
 
paper clip is good check, but the key is that you don't want that side orifice too large. If it's much larger than .060" your fuel pressure to the carb will drop. Shine a light inside and check it out. It's probably good. I heard some of the restoration level year one filter return ports were missing the orifice and people had fuel pressure issues.
 
paper clip is good check, but the key is that you don't want that side orifice too large. If it's much larger than .060" your fuel pressure to the carb will drop. Shine a light inside and check it out. It's probably good. I heard some of the restoration level year one filter return ports were missing the orifice and people had fuel pressure issues.
Thanks for the Info sorry to just jump into your thread i hope i didn't offend anyone..This problem is driving me crazy i so want to drive my car and enjoy it and not worry about it Vapor Locking.
 
UPDATE... I put in the MOPAR vapor canister (confirmed .060" opening on return) with a 1/4" return line to the tank. I am running a mechanical pump on a 440. My fuel pressure used to be 6.5, maybe closer to 6 at idle. Now, I have the pressure gauge jumping all over the place between 4.5 and a little over 6 psi. AT IDLE. As soon as I rev the engine, the gauge settles down to about 5.75. I took the car out for a short run and observed no problem with starvation or power, but I think I am going to consider an electric pump with regulator and return. My 440 puts out about 500 hp and I think I would like that extra safety margin with it comes to fuel pressure. I might add, that I do not just rely on the fuel canister to solve the boiling issue. Recall, I have large headers that run about 325*, or better. The engine compartment on a 90* day cannot get rid of the heat soak from the headers. I went ahead and put one two electric fans with dual relays and a controller that will allow me to set the two fans to come on and go off at any level I chose. More important to solving the temp issue in the compartment, when you turn the engine off, the fans will run anywhere from .5 to 5 minutes. This should be enough time to exhaust the hot air coming from the engine and primarily the headers. I also put a air temp gauge along with Dakota water temp gauge so I can monitor what is happening with respect to air temp at the carb. I will do more evaluations and provide temps and timing in a later post.
Oh, one other thing, on the return line to the tank...i elected to go with a Moroso EFI return adapter that goes on the fuel filler tube. Did not want to cut a hole in tank or sender unit. Seems to work great, especially with so little gas being returned. Should work with an electric pump as well.

Sorry it took so long to get back with results. I decided to rewire the entire circuitry under the dash. I installed a total of 4 Fuse boxes in order to isolate 12+ that 2 35 Amp relays required and one that needed an isolated 12+ for the controller along with another box for 12V ignition. While at it, I replaced the original fuse box. Now, being color blind required help that was always not around, so me and my VOM became best of friends. I tested the dual Hi Lo fans and the controller. All worked as they should. I warmed the engine to 191* and both fans were on and kept the temp steady. I shut the engine off and when through the following test. This was not a real hot day and the engine was run only until it got to Hi control (both fans). I elected to set the key off run setting at 3 min. With this controller, you can go from .5 to 5 minutes of fans on run time after the engine is shut down.
Screenshot 2019-09-12eng temp.png


This test did not convince me that the fans are a cure for heat soak problems and carb boil out. The mass of the block and the fact it is iron would seem to limit the cool down to temps below the temp of the block and even the temp of the radiator, however, the 3 minute fan on duration did greatly affect the cool down of the carb, the headers, the engine compartment air temp and the block at the end of the 3 minutes. Beyond the 3 minutes, I believe that the mass of the block controls the temperature of all parts under the hood, but all below the boiling point of gas.
I will run another test after running the car for a period of time when the temp of the engine should be maxed and the ambient temp is in the 90s.

I ran the test after running the car hard for 15 minutes in 92* summer heat. I added the test to the second row of numbers. Anyone have an observation other than what I stated above. I believe the same hold true for both the short warm up run and the hard run in summer temps. I believe the 3 minutes of fan time is not enough to eliminate the effect of the residual heat given off by the block, however, it reduce the temp of the headers, carb and block. It did not significantly cool down the heads, and the valve covers. Bottom line is it appears that the cool down period of the fans helps to exhaust a significant amount of heat from the compartment and it cools down the the components, however, after the cool down has occurred and the fans shut down, then the residual heat in the block and heads, and of the radiator, will heat the components back up, but it appears it will not heat them up beyond the boil point of gas without ethanol. I am not sure if the fans are a cure all, but I do know that after running in the upper double and lower 3 digits for 5 miles in summer heat did not have the water temp get above 200*. I hope this helps those that inquired about letting them know how the dual fans with controller aided the elimination of the carb boil out.
 
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Sorry for the way the temps came out in the results. Had to screen print the results. Tried to type in the columns, but the post kept deleting the space between the two columns of numbers. You should be able to copy the screenprint and enlarge it. It will enlarge somewhat by just clicking on it.
 
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Thanks for the Info sorry to just jump into your thread i hope i didn't offend anyone..This problem is driving me crazy i so want to drive my car and enjoy it and not worry about it Vapor Locking.
Sonny is the original poster here but we haven’t heard from him in a while. Sonny were you able to solve your fuel boiling and vapor lock issue?
 
By the way- Wix tech support took like 3 weeks to get back to me. For liability reasons they said they could not advise in running the filters in reverse but could also not confirm it wouldn’t work.
 
F5F607C9-1BD4-43CC-955B-96401B9AB565.jpeg
4BF26493-23A7-47F6-81A9-2F52BC065374.jpeg
Sonny is the original poster here but we haven’t heard from him in a while. Sonny were you able to solve your fuel boiling and vapor lock issue?
Hey 68. Been out of touch for a while. Update: sold my holley carb, added Edelbrock avs2 650 carb, sold my Edelbrock rpm air gap and added old Weiand 8009 intake so I could use oval air cleaner, added 1/2” wood spacer, Holley fuel regulator with 1/4” return to tank, electric pusher fan with manual switch, removed headers and added mopar hp manifolds, connected vac advance, still have mechanical pump. All in all way better. Still get some boiling in traffic with temps in the 90s. Electric fan won’t cool temps down but does stop the temp from increasing until I get moving again. Typically runs 180-190. Gets 200-210 in 90 degree traffic. I just don’t drive it mid-day summer any more .
 
Mopar hp manifolds? Wow, the TTI’s reduced underhood temps by 100 degrees vs stock manifolds for mine.
 
Mopar hp manifolds? Wow, the TTI’s reduced underhood temps by 100 degrees vs stock manifolds for mine.
I was using thin cheap racing non coated headers.
 
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