How many are running factory efi on your magnum swap?

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Burlapen

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Curious for those that are, what harness and engine management are you using? Stock stuff? Mega squirt? How much power are you making? I did the carb deal originally but considering tossing the stock efi on.
 
Ehrinburg of Mopar Action had an article on this. I think he mentions final HP. Might be from a few years back.
 
Curious for those that are, what harness and engine management are you using? Stock stuff? Mega squirt? How much power are you making? I did the carb deal originally but considering tossing the stock efi on.

On my '68, I'm using the factory ECM originally for a 1998 3/4 ton truck w manual trans, Hotwire Auto's Hot Rod Harness(4 wire hook up), Ford 40lbs racing injectors, a mildly ported Airgap intake with Massaged Eddie heads & a Hughes Engine's Big Gulp throttle body. The hydraulic roller cam is ground with a 108* LSA and just over 250* @ .050 duration.

The ECM was reflashed to correct the fuel and spark tables for my application. The car chassis dyno'd at 382 hp @ 4580 rpm & 525 ft lbs of torque at 3541 rpm at the rear wheels. This is through full exhaust including aftermarket metal matrix racing cats.

It gets around 14 mpg around town and 17 mpg at 70 mph on the freeway. It does have an overdrive trans & lock-up converter, but I only use that on the freeway.

Airbox2.JPG
 
On my '68, I'm using the factory ECM originally for a 1998 3/4 ton truck w manual trans, Hotwire Auto's Hot Rod Harness(4 wire hook up), Ford 40lbs racing injectors, a mildly ported Airgap intake with Massaged Eddie heads & a Hughes Engine's Big Gulp throttle body. The hydraulic roller cam is ground with a 108* LSA and just over 250* @ .050 duration.

The ECM was reflashed to correct the fuel and spark tables for my application. The car chassis dyno'd at 382 hp @ 4580 rpm & 525 ft lbs of torque at 3541 rpm at the rear wheels. This is through full exhaust including aftermarket metal matrix racing cats.

It gets around 14 mpg around town and 17 mpg at 70 mph on the freeway. It does have an overdrive trans & lock-up converter, but I only use that on the freeway.

View attachment 1715175677


That's a nice set up! Could you take a pic without the air cleaner? Speaking of the air cleaner...where did you get that?
 
On my '68, I'm using the factory ECM originally for a 1998 3/4 ton truck w manual trans, Hotwire Auto's Hot Rod Harness(4 wire hook up), Ford 40lbs racing injectors, a mildly ported Airgap intake with Massaged Eddie heads & a Hughes Engine's Big Gulp throttle body. The hydraulic roller cam is ground with a 108* LSA and just over 250* @ .050 duration.

The ECM was reflashed to correct the fuel and spark tables for my application. The car chassis dyno'd at 382 hp @ 4580 rpm & 525 ft lbs of torque at 3541 rpm at the rear wheels. This is through full exhaust including aftermarket metal matrix racing cats.

It gets around 14 mpg around town and 17 mpg at 70 mph on the freeway. It does have an overdrive trans & lock-up converter, but I only use that on the freeway.

View attachment 1715175677

Wow..That is a nice setup! 525 ft lbs to the wheel is insane. Thanks for the info.
 
The stock OBD2 ECM can be reprogrammed suitably for most applications the factory Magnum block will hold up to, even boosted applications. I am not sure how long SCT will continue selling the programmers, but right now you can still get one and several shops still offer canned tunes for common setups and custom tunes as well.
The harness is no big deal. Use a factory harness, keep what you need, cut out the wires you don't need. If you are not really comfortable with wiring, get the fuse block that the engine harness plugs into from the donor vehicle and just leave the extra wires in place.

IMG_20180512_132023.jpg
 
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what minimum ECU wires needed to run? I got the entire setup minus the intake. Wanted to try and use the 2V TBI on the 2V intake of a 273. Or mill the top out and graft in a 2bbl TBI plate.
 
On my '68, I'm using the factory ECM originally for a 1998 3/4 ton truck w manual trans, Hotwire Auto's Hot Rod Harness(4 wire hook up), Ford 40lbs racing injectors, a mildly ported Airgap intake with Massaged Eddie heads & a Hughes Engine's Big Gulp throttle body. The hydraulic roller cam is ground with a 108* LSA and just over 250* @ .050 duration.

The ECM was reflashed to correct the fuel and spark tables for my application. The car chassis dyno'd at 382 hp @ 4580 rpm & 525 ft lbs of torque at 3541 rpm at the rear wheels. This is through full exhaust including aftermarket metal matrix racing cats.

It gets around 14 mpg around town and 17 mpg at 70 mph on the freeway. It does have an overdrive trans & lock-up converter, but I only use that on the freeway.

View attachment 1715175677

How did you tune your ecm?
 
The stock OBD2 ECM can be reprogrammed suitably for most applications the factory Magnum block will hold up to, even boosted applications. I am not sure how long SCT will continue selling the programmers, but right now you can still get one and several shops still offer canned tunes for common setups and custom tunes as well.
The harness is no big deal. Use a factory harness, keep what you need, cut out the wires you don't need. If you are not really comfortable with wiring, get the fuse block that the engine harness plugs into from the donor vehicle and just leave the extra wires in place.

View attachment 1715175862

Do you have first hand experience with the sct tuner?
 
Don't use this post as a detailed list because I am going by memory, but it's a start.
Inputs include TPS, MAP, IAT, O2, ECT, camshaft sync (distributor), and crankshaft sensor.
Outputs include fuel injectors and IAC.
You also need correct battery and ignition power feeds and ground feeds for the PCM.
This would get it running. Other circuits are optional, such as air conditioning connections. It would also be good to include a data link connector for future diagnosis or programming, so keep those wires too. Always use the correct wiring diagrams to identify all these wires properly and note that most Magnum engines with OBD2 can be wired the same way, but wire colors change from vehicle to vehicle and year to year. A Durango TPS wire could be a different color than a Ram pickup TPS wire, even the connectors are the same.
 
Yes. The SCT tuners work fine for the factory Magnum engine PCM. If you are running a completely stock engine, you don't need the tuner at all, but it can still help squeeze a little more power out of it. Best idea is to get a game plan, what you want for power and what parts you plan to run, and discuss your options with the guys that provide the tunes. They can usually help ensure the component colection is not off base for a fuel injected setup. Once settled on a tuning shop and parts combination, buy the tuner (hand held box) and the tune itself (the actual program) from that shop. Some don't write their own tunes, but still offer the handheld with the tunes from another vendor.
 
good to know, I saw a bunch of A/C cutouts, solenoids, brake light switch (?) and speed controls...figures they were all modern luxury gizmo feedback parts.
 
On my '68, I'm using the factory ECM originally for a 1998 3/4 ton truck w manual trans, Hotwire Auto's Hot Rod Harness(4 wire hook up), Ford 40lbs racing injectors, a mildly ported Airgap intake with Massaged Eddie heads & a Hughes Engine's Big Gulp throttle body. The hydraulic roller cam is ground with a 108* LSA and just over 250* @ .050 duration.

The ECM was reflashed to correct the fuel and spark tables for my application. The car chassis dyno'd at 382 hp @ 4580 rpm & 525 ft lbs of torque at 3541 rpm at the rear wheels. This is through full exhaust including aftermarket metal matrix racing cats.

It gets around 14 mpg around town and 17 mpg at 70 mph on the freeway. It does have an overdrive trans & lock-up converter, but I only use that on the freeway.

View attachment 1715175677
Compartment looks fantastic! Where did you place the computer and PDC? Curious if you relocated under dash? Like the look and starting a swap now.
 
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