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Discussion Starter · #1 ·
I have had this car for about five years and have been continuing the rebuild started by a guy in Kentucky. When I got the car it ran but had some knocks and didn't product anywhere near the power it should. Largely the car was a mess. Fast forward up until a few months ago, I have the car running better than it ever has and have replaced allot of parts. The 295/50/15s I fit under the mini-tub are now basically crayons.

Last week the car vapor locked for the first time while idling in my driveway with an engine temp of 210 (I live in Texas it was like 90 deg). This surprised me because in all my stages of driving the car it had never done this. Whenever the engine gets too hot (~220) I shut it down pop the hood and let it cool. This situation used to happen allot until I got some time/money to start looking into the heat issue. Now the engine holds the temp much better, but if it gets to 210 it vapor locks.

I have moved the fuel lines to the Road Demon carb as far away from the motor and headers as I could without metal surgery and the problem continues. I have a glass fuel filter just above the fuel pump and when she gets hot (200+) you can see the fuel boiling in the filter (some fuel still in the window). Then by 210 its nothing but vapor and I can't restart the motor until she cools to about 160 deg.

Except for small sections (4"-6") connecting to the fuel pump and the gas tank it is all metal line and heat shielded when near the exhaust. The fuel pump looks stock to the 1977 440 (out of an old New Yorker Cop Car). Any ideas and or suggestions would be great.

Pictures!: http://imgur.com/a/XVFVl

(Engine is very dirty)
 

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I agree that an electric pump would help, But one thing
many forget is that modern gasoline is formulated more for efi
motors where it is under high pressure in the rail until the injector opens.
This is a prime reason that carbed engines are more prone to vaporlock.
Try a return regulator to allow the fuel to recirculate. Also do you have any heat isolator
under the carb?
 

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Agree with all of the above. If it were mine I would even block off the heat risers. Having the exhaust, which is maybe 750-1000 degrees or so, running through the intake doesn't exactly help keep the fuel cool.
 

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[]{} todays gas is shit, elec pump is the only way around it
 

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I had to do a return system on my wifes are because of vapor locking in the Ca. I used a bypass style pressure regulator with 3/8" fuel line back to the tank. I put the regulator as close to the carb as I could. It works great....
 

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I used a walbo efi pump on my daughters 66 mustang (ouch)
I used the stock 5/16 for a pressure and ran a 3/8 return.
Been working great for 5 years now. Even on a forb!

Rick
 

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Discussion Starter · #8 ·
Thanks guys! I am going to start looking into an new pump and return line. I'll keep you updated once the parts order comes in and I get everything hooked up.
 

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have to agree with the electric pump and especially the return line. keeping the fuel moving will act as a cooling system for the lines, effectively carrying away the heat that builds up in a dead-head system.

also, blocking off that exhaust crossover is a huge step forward. keeps the carb from turning into a percolator as it sits on top. your overall performance will improve as well.

good luck
 

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You need to get rid of that glass filter before it breaks.

have to agree with the electric pump and especially the return line. keeping the fuel moving will act as a cooling system for the lines, effectively carrying away the heat that builds up in a dead-head system.

also, blocking off that exhaust crossover is a huge step forward. keeps the carb from turning into a percolator as it sits on top. your overall performance will improve as well.

good luck
 

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I see a lot of setups where the tee or regulator is mounted on the inner fender and then the lines are "draped" across to the carb. For some reason, this seems like a bad idea to me, it looks dangerous, and also adds a lot of surface area to the fuel system under the hot hood via those extra lines to soak up heat.

Not trying to ding your setup, more of a question, really.

You said you see fuel boiling in the glass filter (which I agree should be ditched) which is mounted on the inner fender. If it is boiling there, it is most likely doing the same or worse in the carb.
 

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Discussion Starter · #12 ·
I see a lot of setups where the tee or regulator is mounted on the inner fender and then the lines are "draped" across to the carb. For some reason, this seems like a bad idea to me, it looks dangerous, and also adds a lot of surface area to the fuel system under the hot hood via those extra lines to soak up heat.

Not trying to ding your setup, more of a question, really.

You said you see fuel boiling in the glass filter (which I agree should be ditched) which is mounted on the inner fender. If it is boiling there, it is most likely doing the same or worse in the carb.
The lines previously ran up the front of the block and across the intake, this is how they were setup when the problem started. I then moved the lines as far from the block as possible in hopes of keeping them cool.

I agree that the additional surface area exposed to underhood temperatues is inclreased so that may be completely offseting any heat savings I am getting from moving them away from the block. So far I havn't noticed much of a difference and I am considering moving the line back.

I did install a high volume water pump and high flow thermostat this weekend. Seems to have helped but I am not sure my problem is solved. Although I did get to drive it a few times without any vapor lock so its a step in the right direction.
 

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Tank Vented Properly?

Also, if you haven't checked, make sure your tank is vented properly. If plugged up, your pump my be pulling against a vacuum. (Don't ask me how I know, LOL) On the Hemi and 440-6 cars, the factory used a special filter looking thing after the pump called a vapor separator with a 1/4 return line to the tank. It works great here in the Arizona heat. Have one on my 440-6 Challenger.
 
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