Stock Magnum EFI with a cam upgrade.

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Clelan

Clelan

Inferno Red Duster
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I restored an 89 Dodge truck. It has a 360 Magnum, 727, NP241D t-case and Dana 60s front and rear. It was my high school truck, and now it is driven by my son.
At the time, I replaced the TBI with a carb and completely rewired the truck removing all the crap I didn't need. I did a functional but fugly wiring job. And just like so many things, I have never and will never get back to it to do it nicely.
Fast forward a couple years of driving the truck, we found a nice 93 truck with a 360 Magnum, OD auto and air, tilt, cruise. It was a good fully functional stock truck that had been hit in the rear DS corner. A perfect donor for the factory wiring harness, EFI, AC etc.
We have nonproblem doing any of this work, but my problem lies with the stock Magnum engine management. The engine currently in our truck is a stock 5.9 Magnum with a Comp XR264R-12 cam. Will the stock 93 magnum engine management freak out because of the cam? Can it be modified to accept the cam? I am not yet an EFI guy, so any help would be appreciated!

Cley
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I don't think that ODB1 system will play nice with that camshaft. They don't like a lot of valve overlap. It may work because the OBD 1 adaptive learning is more than capable of adding enough fuel via the stock injectors but the intake manifold will be done by 4000rpm's anyway. On top of that you can't flash that controller. So I wouldn't try it. Those early ECM systems like high and constant vacuum at the MAP sensor.
 
I think I am going to try it. Worst case, I'll have to swap the stock cam back in. The intake limiting RPM is not an issue. It's not a high winding application aa it is in a 4x4 truck.

Cley
 
It’ll work fine and compensate slightly while it’s stock. But get it tuned. There are plenty of tuners that can tune it. Look up FRP tuning. Flyin Ryan, he’s in Florida and does mail order tunes and can set up the stock jtec for you. The xr264r is not wild by any stretch and comp lists it as efi compatible.

Flyin' Ryan Performance
 
I sure will. It'll be a couple of months in the making, but we plan to have it complete for mid-August. Big cruise weekend locally!

Cley
 
I did not think the 93 Magnums with the single connector PCM were programmable.

The OBD2 PCM with three connectors from about mid 96 on are definitely programable. This would be a good time to figure out for sure if you want to keep the OBD1 setup or switch to an OBD2 setup before the engine goes in and gets wired up.
 
Forgive me gents, I didn’t notice the obd1 pcm deal from the first post. My advice likely isn’t good but I’ve never messed with an obd1 pcm so I’m not sure. Contact flyin Ryan and ask him. He WILL know. I believe they can be flashed with an SCT handheld but I’m not sure. If you have to change it to an obd2 setup it’s not that difficult.
 

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