5.2 Magnum with Paxton Supercharger in next 12 months, EFI questions.

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gdonovan

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Good Morning; Things have changed in the last decade since I have contemplated this package and I wanted to touch base for suggestions and direction.

I want to state up front I'm VERY familiar with tuning forced induction vehicles being involved with decoding and rewriting the code for Chrysler 2.2/2.5 turbo vehicles from 1985-1991 Logic Modules-SMECS-SBECS. Not a brag, just pointing out I'm comfortable with tuning and keeping alive engines at 30+ psi of boost pressure. It's also a blind spot because I'm very comfortable with those platforms and going to a new platform with different nomenclature will be mildly challenging.

Hell making fuel and spark changes without using a hex editor will be something in itself!

What I have in mind is a 5.2 Magnum (stock shortblock with slightly lumpy roller cam and Indy X cast 2.02 heads with Dougs headers) with a Mopar M1 "4bbl" intake (pictured) with a 90 degree elbow with a single blade throttle body. This would be a nice smooth transition from the Paxton 1200 outlet. I also have a "2bbl" intake but the "4bbl" is the way to go with better plenum volume. I have a set of KRC billet fuel rails and still have to select injectors though I have 8 83pph units kicking around. Slightly overkill but I can always lower the base fuel pressure if need be. I think I also have 33 pph and 52pph low impedance kicking about the shop too. Fuel system would be a stock tank, Carter pump in rear feeding a surge tank under hood with Bosch pump with return back to main tank.

If I did not have a fairly new Mopar tank I'd just go with a new EFI tank but I already have the tank and pumps.

I'm looking to employ the KISS principle. Keep it simple! Just a batch fired, single coil system with O2 feedback, 2 bar map sensor and timing control, fan control nice but not required, idle speed control also nice but not a requirement. Not looking to push to the ragged edge either though this combo should be good for close to 450 hp at 7-8 psi. I'm running a manual trans.. so the stock truck ECM is out for tuning as far as I'm concerned though there is work arounds for that. Something like a MS2 or MS3 system though I'm sure there are other choices out there now.

Just plain old 93 octane fuel, no E85. Planning on just driving the car ('67 Dart) doubt I'll even bother taking it to the track. Let me know what you think and thank you for the input.

Edit: No interest in 4bbl TBI units or anything from Holley.

:lol:

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A Microsquirt would do everything on your list as long as you use a 2 wire (Ford style) IAC valve. AMP also came out recently with an MS3 Pro Mini for those who want something in between the MS2 and 3 lines; it's about the size of a Microsquirt but will do 8 channel sequential fueling using the stock Magnum crank trigger. Neither really are set up for low impedance injectors though; 83 lb high impedance units should be no problem to tune. If you want peak and hold injector control, you can find that on the full sized MS2 (which would need mods if using stock cam and crank triggers) or the MS3Pro Ultimate - but typically smaller low impedance injectors aren't something I would pick for a new build.

From other brands, the Holley Terminator series would be their entry level, same cavaet about low impedance injectors and also they don't support the Magnum crank trigger. Haltech has some good but pricey options as well.
 
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A Microsquirt would do everything on your list as long as you use a 2 wire (Ford style) IAC valve. AMP also came out recently with an MS3 Pro Mini for those who want something in between the MS2 and 3 lines; it's about the size of a Microsquirt but will do 8 channel sequential fueling using the stock Magnum crank trigger. Neither really are set up for low impedance injectors though.
Unfortunately I cannot use the Magnum crank trigger.
 
In that case, easy option for batch fire is a Lean Burn distributor. If you want sequential, Magnum distributor plus a trigger on the crank pulley.
 

In that case, easy option for batch fire is a Lean Burn distributor. If you want sequential, Magnum distributor plus a trigger on the crank pulley.

Correct. Batch fired-single coil I'll be perfectly fine with.

If guys can run these superchargers with a blow through carb and rudimentary spark control then an average EFI setup will be even better.
 
From other brands, the Holley Terminator series would be their entry level, same cavaet about low impedance injectors and also they don't support the Magnum crank trigger.

You can use a dual sync distributor from Holley to run a Terminator setup. Doesn't help the OP, but maybe it helps someone.
 
Unfortunately I cannot use the Magnum crank trigger.

You need to build something like this then. :D

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That's what I did when I was going to run a Magnum EFI setup on my LA motor and didn't have a flywheel option so I could run the stock Magnum CPS.

But no idea if it would work since I scrapped that whole plan for a G3 swap into a different car.
 
You need to build something like this then. :D

View attachment 1716496071

That's what I did when I was going to run a Magnum EFI setup on my LA motor and didn't have a flywheel option so I could run the stock Magnum CPS.

But no idea if it would work since I scrapped that whole plan for a G3 swap into a different car.
With the supercharger not interested in hanging more off the crank snout.
 
Makes sense. If you want the accuracy of a crank trigger you can drill the balance and add magnets. But I am currently using a Lean Burn distributor on a turbo EFI slant six myself. It's adequate.
 
Makes sense. If you want the accuracy of a crank trigger you can drill the balance and add magnets. But I am currently using a Lean Burn distributor on a turbo EFI slant six myself. It's adequate.
Do you have a build thread? I'll like to check it out.
 
Not here, but over on another forum: 1966 Dodge Dart - Turbo slant six

Kind of started in the middle; I had an earlier thread where I had tried using a K-car turbo with somewhat disasterous results and started over with a GT4082.

Eww a Mitsu turbo! Not even a good turbo for a 2.5 let alone a 225, you work with what ya got sometimes. I'm working my way through now.
 
You can just use an "Electronic Spark Control" Distributor like the one in a mid 80's Diplomat as your igntion trigger if you want to make it as simple as possible. The computer you'd just call it a VR sensor with 8 pulses per crank revolution and use the VR input on the megasquirt.

The magnum "distributor" is a cam sensor. So you would need the crank trigger to go with it. Otherwise its of no value other than the wire connections for a single coil.

That being said, I still recommed you go to MS3X / MS3Pro / MS3 Gold and do coil near plug and sequential at least on the wiring. The GM LS type coils have extremely hot spark and are logic run coils so there's no chance of burning anything up in the ECU from running a coil. I am at greater than 10 years without ANY issues whatsoever. The coils are even OE GM ones.

This is my topic: MS3 Pro Sequential Injection + Coil near plug conversion thread
 
I believe I still have one sitting on the shelf. If you need something to test with I'll take a look. and message you. It's free, to anyone who needs it. Just cover shipping.
I'll take it, thank you! 06370
 
Correct. OE Lean Burn distributors are a nice simple locked advance with a magnetic pickup (vr sensor). Pretty easy to use with EFI.
 
the ones i see have vacuum advances so those aren't the one you'd want for this application
I thought he was looking for the dual pick up unit. Unfortunately it may have got tossed. It came from an 86~ 360 truck engine I sourced.
 
You can use the single or dual pick up Lean Burn although aftermarket EFI will use only one of the pick ups.
 
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