Anyone ever attempted this? Not sure if I have the ax15 or nv2500. Won’t be doing the work myself and am having a hard time convincing a shop to help. I love my truck and drive it daily on the interstate but sure wish it could get out of its own way.

 

I "think" the ax 15 did not come out until 92.
do you plan to go carburetor, aftermarket fuel injection, or factory mpi?

 

Looks like I was wrong both ways. Interwebs is telling me mine came with an A535 zumbrota? I’d lean toward efi since I drive it up and down I-95 daily, but would love more than 170hp. But then again anything more than the 90 or so ponies it makes now would be great. The guy doing my timing belt says my current trans wouldn’t hold the 318. Think I might just lower it, stick some cool wheels and tires on it and call it a day.

 

The A535 was known as the NV2500 after the sale of the company.

So yes.

I'd look for a NV3500 to put behind a 318; the NV2500/A535 will work behind the 3.9 however, so that may also be a way to go.

If you find a 1991 donor truck, it'd be easy peasy (IDEALLY one that was rear ended or flipped or had a tree fall on it ... )

RwP

 

The donor vehicle route is a great idea but the rub is that I really REALLY want to keep the manual and I don’t think the 318 was offered with a manual. Half the reason I want the 318 is for the sound (never heard a 4 or 6 and thought “man if only it was louder”). I imagine I could find a 360 magnum with a 5 speed from a yard but I’d guess there would be a good deal of fab required and fitment/weight issues. Luckily my 2.5 is back in bidness with the timing belt sorted but dang I still want to do this!

 

The Magnum 318 was offered in later years with a 5 speed; the 3.9 was offered with a 5 speed (albeit the NV2500 or AX15 those years); and if nothing else, the LA/Magnum bellhousing on an aftermarket 4,5,6 speed should be workable as long as you can get the gearshift back far enough.

I don't have FSM or sales lit for 1991; however, RockAuto DOES list clutch kits and manual transmission parts for a 5.2 for 1991. (They also offer for 1992/1993, where they didn't offer a manual from the factory. Eh. Make of that what you will.)

If you get the same wheelbase Magnum manual, get the rear axle also and the driveshaft; most of the fabrication is then done for you. All with factory correct parts! (Shucks, if it's a 94-96, you can use a return style regulator in the lines to the motor, so it sees the returnless system it's expecting ... use the ECU etc. from that truck, and Robert's your mother's brother!)

RwP