MS3 ULTIMATE Plug and Play Harness by RPS just announced..


still needs to learn
Aug 14, 2004
RPS is going to be offering not only the new Plug and Play MS3 box from DIY AUTO :…/ms3pro-plug-and-play-gnx8487…/

But we will be the ONLY company to now offer Plug and Play harnesses for the MS3 ULTIMATE box as well!!…/ms3pro-ultimate-standalone-e…/

What is the difference, you might ask?
Well, for 1, the RPS harness is going to 100% COMPLETELY CUSTOMIZED TO YOUR NEEDS!! That is right, each harness will be made individually to whatever requirements you may have.

Want the flexfuel sensor included in your harness? DONE
Want extra inputs already wired up for additional pressure transducers or temperature sensors? DONE

Why would you want to go with the Ultimate box? The MS3 Plug and Play box that RPS and another vendor is selling only has a finite amount of inputs/outputs on it. It only has the ability to monitor so many sensors/transducers/etc. The Ultimate box has the following when it comes to I/O's:

10 channel 4:1 or 8:2 programmable peak and hold injector outputs
8 logic level ignition outputs
6 digital inputs
5 digital input/ output
5 PWM outputs
2 digital outputs
12 analog inputs plus built-in MAP, Baro, and internal ECU temp sensor
3 high current digital/pwm outputs
3 digital frequency inputs
4 variable reluctor conditioned inputs

We are still going to sell the regular MS3 PnP ECU, but this will be an option for those that want more. Those that want EVERYTHING in their car monitored and logged.

Our PnP for the Ultimate will come with a base tune to get the car started, but you will need to have a tuner or assistance in setting up all of the additional settings on the ECU (transmission shift points, boost control, etc) programmed. This box is a bit more DIY when it comes to the programming and tuning than the regular MS3 Plug and Play kit that we will be selling.

As for price? We are still working on that, as we are currently making the harness as we speak. Each harness will be customizable to your own needs, so if you need additional inputs wired, that will increase the cost slightly.

We are looking at S1,850-$1,950 or less for this setup. That includes a MS3 Ultimate, Plug and Play wiring harness, and a base tune to get the car started.

This is completely aimed at people looking to have more versatility than the XFI, more tuning abilities than the XFI, and the ability to expand your ECU more than the XFI.

REMEMBER- The MS3 also allows you to use a regular tablet as your dash, so NO MORE $900 DASH COSTS!! Check out this video showing the MS3 Pro and a Samsung Tablet to be used as your dashboard:


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Hit up Reggie to check on the status from Casper's. He has been dealing direct with them. I have not. Otherwise I'd be able to update you.
Nothing here yet, think I was one of the first few to order also with the harness

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Installed with harness or plug and play?

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I run a ms3pro ultimate in my Buick, rewired the complete engine bay. I have 3 cars we have installed the plug and play ms3pro in running around town
How does everybody feel about the unit in general, the ones you have dealt with

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Here is the long and short, the ms3 is the best thing to happen hands down to the buick. the bad part is the guys buying it dont want to take the time to learn how to use what it can do. hell half the guys or more than half the guys dont want to do anything other than get the car running and driving. For the 1% out there that understands how to open a laptop and adjust a ve table or click a auto tune button its the best fucking thing ever. a ton of folks said it wont work and thats all bullshit. so now they have the TT plug and plau unit out which is the EXACT same thing but comes with a few more out/inputs and a built in wideband from what i have read, The issue with the ms3 is there are to many people that will not support it but would rather support the TT guys. so you ask my opinion I think the ms3 is the best hands down if you want to learn.
I am a vendor for ms3pro/diy auto tune as well. But I will not support the product so I am not selling them. I simply do not have the time to do so
I am no expert and my buddy is interested in a unit. He is not on so I will ask for him:
Does this require a jumper harness?
Who supports this unit after purchase? IOW, who does he call with questions
No it plugs directly into the stock computer harness. There are a bunch of cool things that can be done with the system. You can contact any vendor for the system but my guess is they will steer you another way. This thread is just as I thought. The vendors that were so gungho about the system will not be selling them or supporting them due to the release of the new TT unit.