Been kicking around the idea of a fuel cooler for my heap. I have a spare Lockhart oil cooler that's intended to be used on a motorcycle. It has 3/8" hose connections and isn't restrictive. I'd mount it outside the engine compartment somewhere in the air stream, then run an insulated line back to the carb. I don't have any vapor lock issues, just thinking it may help keep the (crappy) fuel from vaporizing so easily and possibly improve performance a tad. Anybody doing something similar, or is this a dumb idea?
That would only cool the fuel if it were hotter than ambient temperature in the first place. Your fuel should already be at ambient when it gets up to the engine compartment. JMO, but a waste of time and adding another spot to get a fuel leak.
To gain performance, you need to super cool the fuel with ice so it stays cold going into the carburetor to cool it down.
I’ve thought of it many times and used a cool can back in the 70’s. Just one more thing to leak I don’t need… but do it if you like….
Remember the Moroso cool cans, there was the coffee can and a big plastic blue one. I never saw any performance gain so I haven't used one in years. Now I use a return regulator and a big pump.
Raising the vapour pressure is more effective at preventing vapour lock, other wise the fuel will always vapourize at the hottest point [close to the engine] Hotter fuel will vapourise and ignite better, so you are better off with cold air [density] and warm fuel. Which requires a jet adjustment [richer] to counteract density. The best method is to raise vapour pressure with an electric pump. But run a full loop fuel line to the engine and back to the tank. Tee off a "deadhead" regulator to the carb.[close as possible] And then add a pressure adjusted check valve in the return line to help hold full line pressure. I've seen this in Carb V8 touring car racing where the regulations only allowed 1 x fuel pump, and only pump gas. When AvGas was banned the vapour lock issues showed up . This ^^^^ was the best remedy within the rules. Return line pressure regulators don't prevent vapour lock because they lower the whole line pressure down to the adjusted pressure. The only performance gains from cooling the fuel was in F1 where the cooler fuel allowed for a greater fuel load into the fuel tank. But back in the turbo era [when petro-chemistry had a real thin interpretation of the rules] they had to heat the fuel in the fuel rails so the "rocket fuel" would vapourize [not atomise] and ignite better. Honda F1 engines had the fuel rails cast into the cylinder heads .
the main problem I seem to have with fuel with some cars is that it boils in the carb after sitting a little while, when I stop driving..then try to start it again. This wouldn't likely help that. But if you have an issue with fuel boiling when you're driving, it might help? if you can find some place cool to put it. That's not likely to leak, under any conditions. which could also be tricky.
If your exhaust isn't tight up against the fuel tank or fuel line, the fuel shouldn't be hot when it reaches the carb. Sure, if you have a mechanical fuel pump on the engine that'll heat it up a bit, but replacing it with an electric pump would do more to reduce the temperature than that cooler can - as long as someone hasn't made something silly like left the exhaust against the tank.
The truth is that enough wooden clothes pins WOULD help keep the fuel in the line cooler. Wood does have some insulating properties, and I assume that if you clipped a few dozen of them side by side along the fuel line under the hood it ̶w̶o̶o̶d̶ would provide some insulation and help keep the line from absorbing engine compartment heat.
Think about something for a minute..... If your car can go 15 miles on a gallon of fuel, how fast is it moving in the lines? By the time it gets from the cooler to the carb it will be hot again. I wondered about that some years ago. I had a cool can on my Chevelle. I could make a run, drive back to the pits and the fuel line coming out of the cool can wasn't as cold as I thought it would be. The can was icy cold but not the fuel line coming out.fuel doesn't flow thu the fuel system as fast as you might think it does.
Just buy a regulator that has a "return line" location. Per the above post, 1/4" return is too small. The recommended return is the same size as your tank to regulator line size. A return will keep the fuel pump cooler and the gas cooler, by design. I'd also cut the pressure to about 5-1/2 psi too. No need for high pressures unless you are racing. Mike
The Corvettes had a insulator and heat shield combo. Check one of the Corvette restoration sites. International had them on some of their trucks also.
One Shot, that's right forgot about that, I have a 70 camaro 307 on a stand in storage has a 2bbl rottenchester It has a factory heat shield insulator deal. Lippy
Never had a cool can but back in the Sixties, I would take a cooler to the track filled with ice, soft drinks and a half dozen grapefruit. Cut a grapefruit in half and slap it over the fuel pump on my flatty. I'd make a run, come in and pull the old grapefruit off and slap another half on. Wasn't real technical but it worked.
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