Upgrading my ms1 to ms3.

When upgrading I also purchased the EBC from DIY.

I plan on running sequential spark, fuel, ebc, a/c.

Is there any reason I need to remove any of my supporting circuits?

 

I suppose you will be using MS3X for full sequential. If this is the case then you only need jumpers from s12 to js9, from tachselect to vrin, and from vrout to tsel. You are missing some components for the vr ckt on the mainboard such as r52 and r56. The cas input needs a pullup resistor. MS3X also handles spark, ebc, and pwm idle so you don't need those circuits on the mainboard.

Read here: http://www.msextra.com/doc/ms3/build_manual.html

 

Funny how much less the MS3x uses:




As for actually removing circuits, I think as long as you have all the circuits built for using the ms3 board and expansion you don't really *need* to remove anything.

 

that's what I was thinking. I planned on leaving everything as is. I'm going to leave all the crap on there unless there is a reason to remove it.

 

Yea. I'd run through the MS3x build manual to make sure everything that is needed is there. The westfield site is down which sucks (but if you need it I have the PDF for his 90-97 MS3x build).

 

did you get an expander board too?

you can't leave your crank input circuit as is, the polarity has to be reversed to match the cam in.

 

yeah i have the expander board too.

will remove. check. now i need to find r56 or an alternative. I should have just sold this thing and bought a new kit. i feel like it's more work to review my board then it is to build a fresh one.

 

Use the bill of materials on the megamanual to find components for the mainboard.

R56 digikey part number: CT94EW103-ND

 

thanks southern. What do i need to remove for the crank input. I'm scouring the build thread but it's missing all kinds of pictures. Ill read through the manual but wouldn't mind some human confirmation.

 

Remove iac1a to js10, remove the pullup resistor at js10, and remove the cap.

The complete vr ckt for the crank input requires adding some resistors, two caps, two transistors, and a diode.

Specifically add r42, r44, r45, r46, r47, r48, r50, r51, r53, r54, r55, c31, c32, d24, q22, q23, and as mentioned earlier the trim pots r52 and r56.

FRT's board has a modified vr ckt from Brain's/Frank's writeup.

 

iac1a goes to js8 which is also jumped to 5v pin. js10 is unused. Are you talking about the cp next to js8?

 

nevermind i just started pulling everything extra off. used frt as reference.

 

Yea remove the jumper and resistor to js8 and remove that cap. js10 was a mistype

Add the components I listed above.

 

Sigh... Good luck.

 

lol... if you need better pictures I have a bunch more.

 

haha what's the sigh for scott?

I jumped vrin & tachselect, tsel & vrout. Just have to make the vr circuit now i think?

I haven't really touched my ms since i made it. Everything made so much more sense then... I feel like a re-re touching this thing now.

 

Because instead of removing all your wiring and extra circuits and adding 20 components, you could have pulled your MS1 CPU, added the MS3 CPU and moved two wires on the underside and been running MS3.

BUT, I do think since you have the expander it wouldn't be a bad idea to remove all your add on circuits and just run them off the expander.

AND you don't need the VR input circuit. You could the crank signal running through the opto circuit, run the cam in the expander, and be good to go. I see no reason to add the VR circuit in this case.

things I'd move to the expander:
spark outputs
fuel outputs
fuel pump (going to 2O, not using high side driver)
the three relays you have on the proto
idle control

 

That sounds good to me. If i don't need to build the VR ckt then I don't need any additional components correct? I'm going to be near the electronics store which is clear across town. (30-45min) Is there anything I need while i'm out?

I'm going to setup the opto circuit again for crank and run the rest off the expander. Sounds the easiest to me.

 

solder wick :P

 

pretty much. i see no reason why you need to buy components.