crawleysam Posted June 20, 2016 Share Posted June 20, 2016 Currently have a ep80 with the carb'd 1e, was going to convert to efi 4efe but going to have to just swap the 1e for a 4e and keep it carb'd (more than likely), any idea as to what size main jet id need for the carb? and anyone know whats involved to put it on bikecarbs? Any help is appreciated. Thanks Sam Quote Link to post Share on other sites
JDMfreak Posted June 21, 2016 Share Posted June 21, 2016 do a search this has been covered a few times Quote Link to post Share on other sites
crawleysam Posted June 21, 2016 Author Share Posted June 21, 2016 do a search this has been covered a few times Pre posting I did a lot of searching and could only find 1 topic on 1e to 4e, 2e to 4e is more common but not really any help Quote Link to post Share on other sites
mccartney11 Posted June 21, 2016 Share Posted June 21, 2016 2e to 4e is exact same Quote Link to post Share on other sites
crawleysam Posted June 21, 2016 Author Share Posted June 21, 2016 2e to 4e is exact same I thought 2e was only efi? i know 1e is definitely carburetor only Quote Link to post Share on other sites
mccartney11 Posted June 21, 2016 Share Posted June 21, 2016 Early 2e's were carb but they had an automatic choke Quote Link to post Share on other sites
Stu Posted June 21, 2016 Share Posted June 21, 2016 (edited) Yeah have a search, 1e/2e carb are pretty much the same in terms of the conversion. Its well worth it, have done it many times over the years to both NA and turbo. Here's a 5efhe conversion in an old EP71 I had Edited June 21, 2016 by Stu Quote Link to post Share on other sites
crawleysam Posted June 22, 2016 Author Share Posted June 22, 2016 Yeah have a search, 1e/2e carb are pretty much the same in terms of the conversion. Its well worth it, have done it many times over the years to both NA and turbo. Here's a 5efhe conversion in an old EP71 I had Have had a look and found and fair bit of info now, just one think i cant really find any definitive information on is what to do about the fuel pump, with the 1e having a mechanical one what should be used for the 4e? some sort of inline fuel pump? Quote Link to post Share on other sites
Stu Posted June 23, 2016 Share Posted June 23, 2016 What you need to end up with is a larger dia line as the feed from the tank to the engine, and a slightly smaller line as a return to the rear. In my case I swapped in a 2e-efi fuel tank and lines in each of the conversions Ive done so it was all pretty easy. However with a carby setup its slightly more difficult. You have a few options really. Probably the best option is to just swap in an EP82 tank and lines - job done. Another option but not the most ideal is to just fit an external fuel pump into the original carb feed line somewhere near the tank. The down side of this is that the factory tank (in a EP7* anyway, not sure about EP80) doesnt have an inbuilt surge baffle so at fuel levels from say 1/3 of a tank and lower you can risk all the fuel running to one side of the tank and the intake picking up air, not ideal on a turbo setup as the mixture will lean out with no fuel. You could setup a lift pump and then run a surge tank in the boot that a main EFI pump then draws from but its work you can probably avoid - you need to keep any setup you have in the boot sealed from the driver anyway due to fumes so you'd probably have to make an enclosure. Another option is to modify the tank to have a surge baffle. Ive done this by dropping a piece of pipe down thru the cover the lines run thru and I sectioned the pipe with the slot horizontally along the surface where the pipe meets the bottom of the tank which allows fuel to flow in from the main tank chamber. I made some small brackets and fixed the pipe to the tank cover so the whole thing comes out. Was quite narrow though so doesn't hold much fuel. Also modified the pickup for the pump to hang inside the pipe inside the tank. Hope that helps, just a few ideas for you. Quote Link to post Share on other sites
crawleysam Posted June 23, 2016 Author Share Posted June 23, 2016 What you need to end up with is a larger dia line as the feed from the tank to the engine, and a slightly smaller line as a return to the rear. In my case I swapped in a 2e-efi fuel tank and lines in each of the conversions Ive done so it was all pretty easy. However with a carby setup its slightly more difficult. You have a few options really. Probably the best option is to just swap in an EP82 tank and lines - job done. Another option but not the most ideal is to just fit an external fuel pump into the original carb feed line somewhere near the tank. The down side of this is that the factory tank (in a EP7* anyway, not sure about EP80) doesnt have an inbuilt surge baffle so at fuel levels from say 1/3 of a tank and lower you can risk all the fuel running to one side of the tank and the intake picking up air, not ideal on a turbo setup as the mixture will lean out with no fuel. You could setup a lift pump and then run a surge tank in the boot that a main EFI pump then draws from but its work you can probably avoid - you need to keep any setup you have in the boot sealed from the driver anyway due to fumes so you'd probably have to make an enclosure. Another option is to modify the tank to have a surge baffle. Ive done this by dropping a piece of pipe down thru the cover the lines run thru and I sectioned the pipe with the slot horizontally along the surface where the pipe meets the bottom of the tank which allows fuel to flow in from the main tank chamber. I made some small brackets and fixed the pipe to the tank cover so the whole thing comes out. Was quite narrow though so doesn't hold much fuel. Also modified the pickup for the pump to hang inside the pipe inside the tank. Hope that helps, just a few ideas for you. Cheers dude, a lot of good information and given me a lot of help! Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.