MS3/MS3X assembly for a Dodge Magnum engine swap

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tcanin00
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Joined: Wed Jul 06, 2011 7:50 pm

MS3/MS3X assembly for a Dodge Magnum engine swap

Post by tcanin00 »

My plan is to use MS3 as a stand alone for an engine swap. The organ donor is a 1992 B-250 van. I plan on using as much wiring from the van as possible since this is going into a 1970 Dart. Initially I'll run the stock SBEC (if that's the correct term for the computer), then piggy back into the harness with MS to data log and make sure it's getting the necessary input signals. Once that's sorted out I'll eliminate the stock computer.
My question is what is the best hardware configuration for a v3.0 board to capture crank and cam input signals? I've searched this forum, read threads, and the Google Doc on Race Magnum that addresses sharing inputs with later JTEC controllers. There doesn't seem to be a definitive answer as to capture inputs for MS. Some advise to run the crank signal through the VR circuit and adjust the trim pots for specific ohms and voltage output, while others opto-isolate it. I know both sensors are open collector and require a pull-up circuit.
The next question is should I build a secondary circuit for the cam input, VR or opto-isolated, and not use the MS3X card initially? Or should I install the card and run it directly to the MS3X card?
I have the card, and want to run sequential injection in the future, but am staying batch injection so that too many variables aren't induced.
billr
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Re: MS3/MS3X assembly for a Dodge Magnum engine swap

Post by billr »

Hmm, you have gone all day with no replies, so I'll toss out my opinion.

I'm thinking a '70 Dart is a fun car, not a daily-driver that has to have minimum down-time as you sort this out. Do you need a stock ECM to control an auto trans, talk to modern gauges, things like that? If not, I think you are going endure extra confusion by trying to use the stock ECM at all. I really think it will be quicker and cost less to just start out with the MS alone.

A key consideration in regards to your other questions is what you intend to use for a crank trigger; give us the details.
tcanin00
MS/Extra Newbie
Posts: 5
Joined: Wed Jul 06, 2011 7:50 pm

Re: MS3/MS3X assembly for a Dodge Magnum engine swap

Post by tcanin00 »

billr wrote:Hmm, you have gone all day with no replies, so I'll toss out my opinion.

I'm thinking a '70 Dart is a fun car, not a daily-driver that has to have minimum down-time as you sort this out. Do you need a stock ECM to control an auto trans, talk to modern gauges, things like that? If not, I think you are going endure extra confusion by trying to use the stock ECM at all. I really think it will be quicker and cost less to just start out with the MS alone.

A key consideration in regards to your other questions is what you intend to use for a crank trigger; give us the details.
Thanks for your response, billr!
You are correct in saying the Dart is not intended to be a daily driver. I am still in the rust repair stage and haven't even started the engine swap yet. I am trying to educate myself as much as possible on MS while I have the time to do so.
The stock ECM does have some control of the A518 transmission, like overdrive lock-up and part throttle unlock. It also receives VSS input. I think it sends the signal out to the speedo, couldn't tell from the schematics though. I would like to keep the cruise control, which is partially operated by the ECM.
The van is complete and running, so I have the entire harness at my disposal. I would like to take the engine and it's ECM as a complete unit and swap them to the Dart so that I have a baseline to start with, then take control of it with MS.
I will be using stock Magnum sensors. The crank sensor is an open collector hall effect sensor triggered from an 8 tooth pattern on the flywheel. The cam sensor is also an open collector hall effect sensor in the distributor. It uses a half moon single tooth to detect phasing.
I hope this helps explain my intent and simply what I would like to do with MS.
Matt Cramer
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Re: MS3/MS3X assembly for a Dodge Magnum engine swap

Post by Matt Cramer »

Use the VR inputs with pull ups; they work fine for the Chrysler hall effect sensors. We've used them successfully with an MS3Pro on a 318 Magnum powered Grand Cherokee.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
tcanin00
MS/Extra Newbie
Posts: 5
Joined: Wed Jul 06, 2011 7:50 pm

Re: MS3/MS3X assembly for a Dodge Magnum engine swap

Post by tcanin00 »

Matt Cramer wrote:Use the VR inputs with pull ups; they work fine for the Chrysler hall effect sensors. We've used them successfully with an MS3Pro on a 318 Magnum powered Grand Cherokee.
Thanks answering this, Matt.

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