FHey Guys! I thought i remembered reading on here about the possible compatibility of the Ford Lightning fuel pump for the XJR. Im thinking thats going to be my next mod. Does anyone have any idea on where to find a heavier flow fuel pump, and what injectors i should use? Or, any help on how to access the fuel tank? Thank you very much!

 

the lightning uses two pumps like our cars, the fuel pump is 100 something lph, pretty much the same size and some use the same ford connector. as long as it fits in the bracket and you can splice 4 wires any aftermarket 255lph pump should work.


best way to access the tank is taking out the rear seats, parcel shelf, speakers and then grinding a cutout flap.

 

1995XJSGuy,

You have two fuel pumps in there, good idea to change them both now. Even tho only one is dead. Once you've completed the job you'll know where this comes from!

 

Hmmm didn't know we could use 255lph pumps in our cars. Lots of people are against cutting the parcel shelf......I'm not.

 

I have had 2 x 255lph pumps last eight years. Needs adjustable FPR and bigger return side connectores. Otherwise fuel pressure is way too high and not in control.
Stock pumps are ~120lph ones.

 

I have had 2 x 255lph pumps last eight years. Needs adjustable FPR and bigger return side connectors. Otherwise fuel pressure is way too high and not under control.

EDIT: Stock 4.0 R injectors are 360cc / 34lbs @ 3bar / 43 PSI . You can go quite far with those if you eaise fuel pressure. If you use E85 - then another story.

 

I do not understand why would one want bigger flow pumps than stock on a stock fuel system. The extra flow will do nothing good as it has "nowhere to go" and will just cause much higher bypass/return flow pass the FPR which may overwhelm the FPR and cause poor running.

Modified (race) engines are another story.

 

in theory if you max out the injector duty cycle you can just raise the pressure and continue.

if you don’t have a heaton it may be of some use to do this. adding the aj34 rail increases the fuel pressure and allows you to run the 500cc@? psi injectors

 

When I had 4.0 TS - dynod 522bhp...stock 4.0 injectors were just fine. FPR adjusted to 48-50PSI ( so sotock inhectors can handle well up to 550-570hp with TS ) I still have a set of 4.0 style side feed 550cc injectors which were calibrated within 1%. They were never used in my engine. Later with totally new setup first 590cc and now 870cc ( 4.2 style EV14 injectors ). These need fully programmable ECU to work properly.

 

Here are photos of the parcel cutout during and after pump replacement. I actually put a large welding blanket over the top of the fuel tank and tack welded the "flap" back into position before sealing the seam. Live dangerously! If you tack weld back in place, you can cut into the speaker area for more access to the hose attachments. And here's a related thread: Fuel pump replacement options - Jaguar Forums - Jaguar Enthusiasts Forum

 

don’t cut into the speaker cutout. put a rubber floor mat on top of the hard line. use copious amounts of tape to avoid rattles

you might accidentally break the glue on your third brake light doing it this way. perfect opportunity to throw it in the dumpster