YJ Stroker - MS, Split Second, AEM Questions

[codycowgill]

Ok, so after 5 long and tedious years my 4.7 stroker that was originally a 4.0 from a 95 YJ is installed and idling in my 94 YJ. Everything is hooked up to just the factory ECU at this point just to get it to start and idle.

Now are my questions. I have a MSII computer that was purchased about 3 or 4 years ago and put together that I could wire into the factory harness, but I have never personally tuned any vehicle and I would only consider myself a beginer as far as wiring is concerned, let alone doing any circuit changing on the MS board if need be (if resistors need to changed or anything). I don't really want to have to install two sensors for everything or change the CPS to the harmonic balancer.

I have read a lot of people use Split Second or AEM for timing/fuel control with there turbo or supercharger, but do either of these tuning packages have the ability to change the cam and displacement settings?

And it seems like every application where Split Second or AEM is used, it is in a OBD2 Jeep 4.0. How will either of these systems work with my OBD1 install?

I am not to concerned with smog issues, as I can register the Jeep in Alaska if need be, but of course getting it to pass smog in California would be better.

What do all you YJ stroker experts think?

Thanks in advance!

[gradon]

Getting info here about MS will be a little difficult. For $500-600, you can buy a tuned Unichip from Hesco that you can wire into your YJ.

[codycowgill]

^^^^ The Unichip can account for the aftermarket cam? I have read up on the Unichip/Hesco route, but am just not sure if it would be able to adjust for the cam.

[Cheromaniac]

I also have OBD 1 and I'm running the factory ECU.

[jsawduste]

With due respect.........You are way over thinking this.

If you have the correct injectors. Plus an adjustable fuel pressure gauge you have the tools to make your stroker run and run well with the factory OBD1 ECM.

If you want a little more then you might consider the CPS timing trick that Silver posted about. Some like adjustable MAP sensors but I don`t think they are worth much.

Your concerns on displacement and cam are addressed in the injector/FP add on`s.

[Cheromaniac]

John's correct. You really don't need the Megasquirt (or any other aftermarket computer for that matter) to get the stroker running right if you have OBD 1.
As long as your injectors are close to the correct size, you can fine tune the fueling either with a MAP adjuster (works well on OBD 1) or an adjustable FPR. I'm using Ford Racing 24lb injectors, stock FPR, a homebrew MAP adjuster set at 5.3v, and my engine runs beautifully. The HC and CO emissions are also much lower from my stroker than they ever were from my original (but healthy) 4.0.
You can also advance the ignition timing by slotting the bolt holes of the CPS and moving the sensor closer to the vehicle's centerline but since you live in CA where you don't have the luxury of high octane gas, you'll need to watch out for pinging.
What are the build specs of your 4.7 stroker?

[codycowgill]

Thanks for the help guys.

My brother actually blue printed the stroker from the ground up in 2008 and had a machine shop in WA build it while I was in CA. Since then, the spec sheet for it has been permanently misplaced. I know it was a 4.0 from a 95 YJ, bored to make it a 4.7L stroker, has the 4.2 crank and free floating piston kit from Hesco, and a Comp cam. That is about all I know. Now the stroker is installed in a 94 YJ in my garage in CA and my brother has since moved to Boston and all but forgot about the project.

I think I have a good handle on the FPR and MAP, but I do have one more question about injectors if anybody can chime in.

Will either of these designs, I believe one category being design 1 or 2, and the other being design 3, be a direct bolt in for my 95 engine?

design 1 or 2
http://www.ebay.com/itm/87-93-5-0-MUSTA ... 8941830217
http://www.ebay.com/itm/24-LB-24LB-FORD ... 4336634595
http://www.ebay.com/itm/Mustang-24-24lb ... 8608265368

design 3
http://www.ebay.com/itm/Mustang-Racing- ... 0216463497
http://www.ebay.com/itm/290588738932?_t ... 53&vxp=mtr

Again, thanks for the help!

[Cheromaniac]

All of the injector sets you mentioned will work.

[codycowgill]

Thanks. The design 3 is a better design correct? Or is it really just a matter of opinion.

[Cheromaniac]

The four-orifice injectors will give a more even spray pattern for better fuel atomization.