Aftermarket EFI on a Magnum- your experience??

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MRGTX

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Which system did you use? How did it work out?
Would you do it again?

I was pretty psyched about the Edelbrock Pro Flow 4 but they're not available for our Magnums (LA small blocks only).
 
no experience with it, but holley terminator now has a universal system out. I wonder if it will work on the magnum.
 
You can run it with megasquirt, including any sensors and throttle bodies you want. I did an LA engine but the ideas work the same. Been running it on my engine for 4 years and it's done well. You just have to source your parts. You'll have to buy a wideband O2 kit (I have an AEM) but other than the wiring it's not a big deal.
 
I believe that plenty of the systems will work. Just fine.

FiTech, Holley Sniper etc. use a throttlebody with a standard four barrel (or two barrel) carb bolt pattern. The sensor inputs are all compatible of course. It's just the Edelbrock Pro Flow 4 that comes with it's own manifold (with fuel rails, I believe) which seems to get universally good reviews) that is not directly compatible with the Magnum heads.

Drill the heads for LA bolt pattern and bolt the pro flow4 on.

Is the Edelbrock system better-enough to justify the extra expense?
 
no experience with it, but holley terminator now has a universal system out. I wonder if it will work on the magnum.
What is the difference with the Terminator system? Does it not come with its own ECU like the Sniper and other systems? I'll have to look that one up.

You can run it with megasquirt, including any sensors and throttle bodies you want. I did an LA engine but the ideas work the same. Been running it on my engine for 4 years and it's done well. You just have to source your parts. You'll have to buy a wideband O2 kit (I have an AEM) but other than the wiring it's not a big deal.

What's "it"? The Terminator? The stock Magnum FI?
 
What is your planned use? If ypur using it for Daily driver and do a lot of driving go with the port injection with sequential. That would look like the Pro-flo4 or stock with a megasquirt. Would be for that little extra mpg.
I have heard good things about the holley sniper kits as well. If you go that route hit up @Johnny Mac as he helps the guys out.
 
What is your planned use? If ypur using it for Daily driver and do a lot of driving go with the port injection with sequential. That would look like the Pro-flo4 or stock with a megasquirt. Would be for that little extra mpg.
I have heard good things about the holley sniper kits as well. If you go that route hit up @Johnny Mac as he helps the guys out.
Thanks for the shout out! I sell a bunch of snipers and we have good luck with them. I can gladly set you up with a compatible distributor, coil, sniper, fuel pump, if you go that route.
 
What's "it"? The Terminator? The stock Magnum FI?

You just toss the stock magnum computer and run the engine with all it's original parts if you would like on the Megasquirt. It's real easy to change a sensor, injectors, etc later if you upgrade. A couple of menus and you're done. You will have to add a pull-up resistor to get the cam sensor in the distributor body to work but that's not a big deal. My LA 340 has all GM sensors, a holley throttle body, the stock magnum distributor for a cam sensor, and a 36-1 wheel on the crank. I have sequential multiport injection with coil near plug coils from an LS based truck engine. Car started and idled the first time I ever cranked it and it has autotune. I have an MS3 Pro.
 
Photo on my engine which is a 340:
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Hjo3L-o1inJIK7IDUPKG1RBbf4dRFk3KPlSta5NRb9XTjRgSS44-EXjiyl6xO2z5zT11ilxvyj3g35Ey_eQ=w703-h937-no.jpg


I'm not sure if you can even get the M1 intakes anymore, but you could always get the Hughes airgap and do a setup like this. I like this universal Holley 1000 cfm throttle body since the IAT sensor is also part of the throttle body
 
Photo on my engine which is a 340:
View attachment 1715447437
View attachment 1715447438

I'm not sure if you can even get the M1 intakes anymore, but you could always get the Hughes airgap and do a setup like this. I like this universal Holley 1000 cfm throttle body since the IAT sensor is also part of the throttle body

Great looking set up. I am going to do the same thing to my 5.9 magnum engine, but I am going to also use the GM LS computer. I have to swap teo of the injectors and ignition coils. Ls firing order is diffrent and get it swapped in the computer and retuned.
 
Which system did you use? How did it work out?
Would you do it again?

I was pretty psyched about the Edelbrock Pro Flow 4 but they're not available for our Magnums (LA small blocks only).


I run a reflashed factory Magnum JTEK computer that has been reflashed on my 408" Magnum. I had a guy on the east coast tune my set-up. It took 3 tunes to dial it in. It was a simple process and it works very well. I did use the Hotwire Auto Hotrod harness, which made the install plug and play.

When I get ready to supercharge my next build, I'll switch over to the Holley Terminator ECU. The reviews, flexibility and added functionality it offers are attractive. The self-learning and tuneability are said to be second to none.

My buddy runs the Proflo 4 on his RB. It's been everything they said it would be. His car runs great.
 
Great looking set up. I am going to do the same thing to my 5.9 magnum engine, but I am going to also use the GM LS computer. I have to swap teo of the injectors and ignition coils. Ls firing order is diffrent and get it swapped in the computer and retuned.

If that's the case you should just be able to swap the pins for cyl #4 and cyl #7 in the harness.

I would think what you need to mimic the LS cam and crank sensor and tuning it isn't going to be much cheaper than going with a stand-alone. I saw the MS3 Gold Box for $850.

Glad you guys like the setup I put together.
 
I just got it warmed up the first time last tuesday, fresh engine and all. Follow my "how big can a 5.2 get" thread for further information.
 
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If that's the case you should just be able to swap the pins for cyl #4 and cyl #7 in the harness.

I would think what you need to mimic the LS cam and crank sensor and tuning it isn't going to be much cheaper than going with a stand-alone. I saw the MS3 Gold Box for $850.

Glad you guys like the setup I put together.
Well so far with the LS computer/ Harness I am only into it for $150. My friend said he would tune it fir me pretty cheap. The crank and cam sensor I am going to use it $320 for them both. The crank sensor is a GM sensor and the tone wheel is made to be used with the factory mopar crank pully. The cam sensor is a jeep 4.0 and a adapter to mount it wear the factory Dist goes. But I do like the megasquirt set up a lot.
 
I run a reflashed factory Magnum JTEK computer that has been reflashed on my 408" Magnum. I had a guy on the east coast tune my set-up. It took 3 tunes to dial it in. It was a simple process and it works very well. I did use the Hotwire Auto Hotrod harness, which made the install plug and play.

When I get ready to supercharge my next build, I'll switch over to the Holley Terminator ECU. The reviews, flexibility and added functionality it offers are attractive. The self-learning and tuneability are said to be second to none.

My buddy runs the Proflo 4 on his RB. It's been everything they said it would be. His car runs great.
What guy did you use? Hemifever in NC or PIE in NC?
 
Where did you get these valve covers to mount your coils?

They are the regular fabbed aluminum valve covers from Ebay. I drilled holes and used some stand-offs to mount my round coils. Some coils don't need stand offs like that.
 
Which system did you use? How did it work out?
Would you do it again?

I was pretty psyched about the Edelbrock Pro Flow 4 but they're not available for our Magnums (LA small blocks only).
I know its more money but install a set of trickflow heads, then you can run the intake. Or see about getting the edelbrock intake drilled for the magnum bolt pattern
 
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