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Fuel injection upgrade

lundtland

NAXJA Forum User
Location
Maple Valley, WA
I have an 1987 Wrangler. Stock 258 with the ever popular electronic carb. I have access to cars through a tow company and they get a lot of Cherokees. Can the fuel injection system be taken off one of those motors and added to mine. I'm sure I would have to change the fuel tank or at least change some components to supply the correct fuel pressure, and I will need the FMC fuel management computer.... are there other things I need to consider?
 
The fuel and ignition are integrated. You will need to change the flywheel/flexplate along with the tranny bell housing so you can add a crankshaft position sensor. Hesco makes an aftermarket one that runs from the harmonic balancer, but they are pricey. You will need the distributor and coil as well. The distributor houses the camshaft position sensor. It would be easier to use the Renix from the pre 91 XJ IMHO. The newer stuff is too integrated into the dash and other functions.

Either way, you will need a fuel tank with a return line. The XJ tanks have the pump built in, but you can run an external tank. Remember, you have to be able to deliver roughly 50psi.
 
Thank you for the information.
Do you have any suggestions that would not be so complicated. The engine I have is in good shape and was rebuilt a few years ago. I runs fine until I get into steep climbing... then it floods out and turns into a real bitch.... I have read about the nutter bypass and I have opened up the air bleed tubes and that helped a little. Maybe there is an after market carb that would operate better.
 
I have a 258 with Howell TBI kit in my YJ. That kit is basicly just a Chevy Blazer 4.3 TBI system... in my opinion that works quite well and with HEI ignition I think that motor won't get any better with the stock head. Gas mileage is very good on 38" tires with 4.56:1 ratios. A friend of mine had a '90 XJ automatic on 38's with 4.88's and he was getting worse gas milage then me. There's a writeup here on how to make a junkyard TBI setup from Blazer parts on a 258: http://www.bustedjeep.com/projects/junkyardtbi.asp

:D
 
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