Hello, I have done countless hours of research over the past few years.. I have finally started my build after rounding up parts and buying an expo. I have a 99 Mazda B2500 2.5 5speed. the donor is a 1996 5.0 expo 2wd auto. i bought it on a whim for $600. I really wanted a later model expo as I would have had no problem swapping in the PATS.

Any one one here have simple solutions for:
fuel pressure correction? should i do returnless rail, or get a sending unit from a ranger with a return
vss or speed sensor solutions?

 

For fuel, the simplest would be to get the fuel rail from 1999+ explorer 5.0l.

Not positive but I think the trans mounted VSS, '96 Explorer, and the rear axle VSS, '99 Ranger both read approx. 8,000 pulses per mile via variable reluctance, which is sent to ABS module and GEM, then to PCM and speedometer after ratio/tire size correction.
So you should be able to use the Rangers rear axle VSS with/to explorer harness.

 

Thank for the reply, I have bought a returnless expo fuel rail. I'll hit an expo forum

 

I'd suggest modding the fuel system to become a return type.

The returnless pump/FPR in your fuel tank is rated at almost twice the pressure the '96 Expo EFI system expects.

Factor in you'll loose the reduction in fuel pressure under high vacuum conditions and I think your '96 EFI is going to be in trouble.

Perhaps dropping down in injector size might get things close enough.

There's already a fuel return at the back of the '99 Ranger/B2500 fuel filter so simply removing the FPR in the tank and then piping the fuel return from the Expo fuel rail to the return line is a pretty simple solution.

You'll want to be careful with the speed signal. The ABS handles the signal using the ABS sensor at the rear axle. The Expo uses a gear driving VSS at the back of the transmission.

Both systems generate exactly the same signal, so if the two systems get tied together, you'll get a double reading at the speedo and internal to the PCM.

You could simply leave the speed signal wire open between the B2500 and Expo harness. That way, the PCM see's the transmission VSS signal, the B2500 see's the ABS's signal.

Alternatively, leave the VSS unplugged from the Expo harness, marry the Expo and B2500 speed signal wires and let the B2500 run the show.

Gotta say, since your B2500 does not have PATS of any kind, the non-PATS '96 Expo is a great option. Yea, a '99 Expo would have been easier with the fuel system and nearly plug and play with the wiring, but you'd have had to add PATS to your truck, or tuned it out of the PCM.

Either way, some mods were going to have to be made, and since the fuel system is not that big a deal, I'd say you're in a great position.

My own '02 is '96 powered so I did not have to muck around with PATS but did have to adapt the fuel system into a return type.

 

Ok I'm seeing on the one thread about non return vs return type fuel system the guy said that the ranger fuel pump runs at a higher pressure than exp/mount expects, the guy said he may run into trouble at high vacumm conditions like full throttle. my 302 is 97 and has return system which i used adaptor to return fuel at filler neck and my test showed fuel pressure to be ok at idle, that doesn't mean much on highway doing 55 or 60 when she is going uphill turning 33s. so am i missing something? the last trouble code i have is too lean both banks and she doesn't like to idle cold, have to feather gas for maybe 30 seconds to get her to idle. then she runs good, ws told this is leak at intake but when i sprayed it with carb cleaner..nothing. any ideas would be appreciated