4.6 PI Motor Swap With OBD-I Setup 1992-2000

[gadget73]

It would have been easier to put a 302 in it. By the time it was all done, I really wish we had.

[sly]

it's running now (and boy does it haul ass now too). Which I'm very grateful for. Still need to take a trip and see what kind of mileage it really gets just puttering along on the highway. No real clue what it gets in town either since it was blowing by that one spark plug on the mileage run I made. I'd wager 17 city and 25 hwy.

[Chevyguy]

It would have been easier to put a 302 in it. By the time it was all done, I really wish we had.

I have started on the idea that this may be the best fate for the 91-95 4.6 Cars.

[sly]

HRG: You wouldn't happen to remember what the belt size was on this mess would you? My string slipped and my mark came up at 93 inches. I'm trying to order belts for all of the cars and this one just doesn't seem to fit anything and of course the markings on the belt that's on there are completely gone.

[sly]

Also, for anyone who cares... I wish we had just put the PI longblock and PI intake on this mess and only re-routed/extended the injector wires to fit and run with it. After a tune with the later/larger MAF, it would have caused a LOT less headaches.

[sly]

HRG: You wouldn't happen to remember what the belt size was on this mess would you? My string slipped and my mark came up at 93 inches. I'm trying to order belts for all of the cars and this one just doesn't seem to fit anything and of course the markings on the belt that's on there are completely gone.

never mind. pulled the belt to measure it and found remains of the markings. 91 inch. 2003 stock size. I guess the crank pulley is that much smaller or the tensioner/idler positions are that much tighter since the rest of the accessories are original to the car.

[gadget73]

Also, for anyone who cares... I wish we had just put the PI longblock and PI intake on this mess and only re-routed/extended the injector wires to fit and run with it. After a tune with the later/larger MAF, it would have caused a LOT less headaches.

I tried that, it failed fairly badly. Don't know why, but it simply wasn't having any of that. Ran lovely on 7 out of 8, which isn't terrible statistically speaking. Forget which hole was dead, but moving the injector and the coil wouldn't move the problem, though it had both fuel and spark. Scope even told me they were kosher relative to one another. Only thing I can figure is that the spark was not at the proper time relative to piston and valve position for reasons I just don't get. It doesn't have a distributor like a sane engine, so its not like its something you can sort out easily if the crank trigger design is different enough to screw with how all that works.


The OBD2 swap was done in a fit of desperation, definitely not out of any desire to have fancy-ass extra electronics in the mix. In the end it worked, but it wasn't any fun. I will say that it solidified my lack of desire to ever do such a thing again.

[sly]

But you were trying to do it with the coils instead of the stock coil packs right?

[86VickyLX]

But you were trying to do it with the coils instead of the stock coil packs right?

Correct, but by then the whole thing was a clusterfuck.

Thing would have run fine with the PI shit and the older timing cover and such. But having all of the 03 stuff plus the theory of 'this should work' really messed it up.

[sly]

That's what I'm thinking. Plus, the EDIS has a tach pin.

[86VickyLX]

That's what I'm thinking. Plus, the EDIS has a tach pin.

You could unmodify it. But you'd have to change the solenoids in the tranny again.

[sly]

You could unmodify it. But you'd have to change the solenoids in the tranny again.

Nope. the new solenoid will work with the older computer as it's a higher resistance coil. Does the same job with less power used. The control mosfet that powers it doesn't give a damn as long as the power usage isn't more than it's capable of... which the old solenoid would be on the newer PCMs.

I would also need a 93 PCM and edis module and a complete 93 engine/trans harness and then something like a quarterhorse and lots of time... and no. It works now, but there's a better way to PI swap a pre-OBD-II aero than what was done here.

[86VickyLX]

Nope. the new solenoid will work with the older computer as it's a higher resistance coil. Does the same job with less power used. The control mosfet that powers it doesn't give a damn as long as the power usage isn't more than it's capable of... which the old solenoid would be on the newer PCMs.

I would also need a 93 PCM and edis module and a complete 93 engine/trans harness and then something like a quarterhorse and lots of time... and no. It works now, but there's a better way to PI swap a pre-OBD-II aero than what was done here.

True. And I plan on this when the 94s engine gives up haha.

[gadget73]

I can offer some kerosene as an easier way to solve that problem.

[sly]

when it dies... I may take you up on that offer. But apparently you did such a good job on the OBD-II hack that it should run for a long time.