I’m tired of vapor lock in 100 degree weather with my 32/36 webers. Korman installed an electric fuel pump and fuel pressure regulator at 3psi. Still vapor lock. Biting the bullet and putting on a mega squirt injection system. The e24 system will fit. What else do I need, and any thoughts to help with this swap would be greatly appreciated. Dave
Carbs to fuel injection.
- Thread starter Pflyer
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Dave,
I have been involved with and or done 3 Coupe carb to FI. There are several experts on the Forum that can do the conversion for you, consult, sell you parts or you can do it yourself depending on your level of mechanical knowledge. You could probably first do a search on the Forum to get yourself acquainted with the process. There are several detailed posts on the subject and I think your first and smartest move. You have a number of sources on the East Coast like VSR and several members that will probably pitch in. Here are 3 shots of what they look like. My Sahara Coupe is MegaSquirt, wasted spark, 284 Shrick cam in a 1984 635 CSi Euro 10:1 CR engine and it is very driver friendly. Always starts. My Turkis Coupe uses an Emtron ECU and the Link ECU also is a good choice.
Out here in the West lots of knowledge resources like the SoCal Mafia, SFDON and others. The list of parts are not that extensive but are not easy to find. Once you understand what you need a better place to post this in the For Sale or Want to Buy section.
Regards, Jon
I have been involved with and or done 3 Coupe carb to FI. There are several experts on the Forum that can do the conversion for you, consult, sell you parts or you can do it yourself depending on your level of mechanical knowledge. You could probably first do a search on the Forum to get yourself acquainted with the process. There are several detailed posts on the subject and I think your first and smartest move. You have a number of sources on the East Coast like VSR and several members that will probably pitch in. Here are 3 shots of what they look like. My Sahara Coupe is MegaSquirt, wasted spark, 284 Shrick cam in a 1984 635 CSi Euro 10:1 CR engine and it is very driver friendly. Always starts. My Turkis Coupe uses an Emtron ECU and the Link ECU also is a good choice.
Out here in the West lots of knowledge resources like the SoCal Mafia, SFDON and others. The list of parts are not that extensive but are not easy to find. Once you understand what you need a better place to post this in the For Sale or Want to Buy section.
Regards, Jon
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Thanks Jon. There’s a nice intake from a 633 on eBay for $350. The airbox is not included. This is just the beginning of the exploratory. My mechanic in Greenville is incredible. He’s in the process of a complete restoration of a customer’s e9, and his own 850ci. I’ll continue the process to get it right. I’ve done much of the work myself on the ‘74 e9, so the help from members is very welcome. Thank you. Dave
NMNA: There's a 1980 633 just outside of Washington D.C. on Craigslist.
bengal taiga
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I can understand an appreciation for fuel injection over carburetion. And, if you are dead set against keeping your carburetors, stop reading now as I do not wish to offend.
You mention vapor lock, but this covers many different circumstances, some of which may be more easily surmountable than a fuel delivery swap. I would wager that there are still a few stock carburetor-fed M30's operating in similar hot conditions that do not suffer from the problem. Could it be that you are using an ethanol blended gasoline? Blended fuels likely have a lower boiling point than non-blended gasoline, making it more prone to vaporizing in hot weather. So, you might try ethanol-free fuel with a higher octane rating.
An electric fuel pump may be a good start to overcoming the problem, depending upon its placement. Conventional wisdom suggests that such a pump is best mounted near the gas tank at the rear of the car, far from engine heat. Although fuel pressure is considerably higher with fuel injection, increasing line pressure above 3psi, might also mitigate or deter fuel vaporization. Other thoughts include reducing underhood temperatures with more efficient cooling fan/s, exhaust wraps, insulating fuel supply lines and depending upon emissions issues, ensuring that the fuel system is vented.
You mention vapor lock, but this covers many different circumstances, some of which may be more easily surmountable than a fuel delivery swap. I would wager that there are still a few stock carburetor-fed M30's operating in similar hot conditions that do not suffer from the problem. Could it be that you are using an ethanol blended gasoline? Blended fuels likely have a lower boiling point than non-blended gasoline, making it more prone to vaporizing in hot weather. So, you might try ethanol-free fuel with a higher octane rating.
An electric fuel pump may be a good start to overcoming the problem, depending upon its placement. Conventional wisdom suggests that such a pump is best mounted near the gas tank at the rear of the car, far from engine heat. Although fuel pressure is considerably higher with fuel injection, increasing line pressure above 3psi, might also mitigate or deter fuel vaporization. Other thoughts include reducing underhood temperatures with more efficient cooling fan/s, exhaust wraps, insulating fuel supply lines and depending upon emissions issues, ensuring that the fuel system is vented.
jmackro
Well-Known Member
I had the same thoughts as bengal taiga: if eliminating vapor lock is your only objective, switching to FI is a "swatting flies with a sledgehammer" kind of approach. Admittedly, fuel injection brings other advantages, but sourcing and installing the FI hardware and setting up an aftermarket controller don't seem like minor projects.
As bengal taiga suggested, you may not want to get into diagnosing your vapor lock problem, but if you're willing to share it, I'm curious what kind of a job Korman did on the electric fuel pump conversion. Such as where they mounted the pump, what type of pump they used, where the regulator is, whether you have a vented filler cap, ... Even with ethanol fuel, a properly setup electric fuel pump is generally the fix for vapor lock. Heck, my mechanical pump, sucking ethanol laden fuel to the engine from the tank, never produces vapor lock (though admittedly, I do live in a cool climate).
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