I'm just about done putting the wiring harness together. My question is, it's my understanding that when you cut 2 teeth out of the CAS you only need the the one VR circuit built into the MS. Is this correct?

Also, all the information that i've read here says that they need to be opposing teeth but which 2 teeth do you cut out?

Then if you run it like this how do you wire the CAS up? I've reread the FAQ a a million times. I bet i could resite the darn thing in my sleep It explains how to do things for 2 VR circuits very well but i'm a little lost with the utting 2 teeth.

 

yes

It actually doesn't matter... as long as you stab the CAS so that it matches up with your wheel decoder settings.

Wire the Ne+ wire to the "tach" pin on the MS, and wire Ne- to one of the MS's ground pins.

 

awsome, that takes care of all those questions.

 

wow this helps allot. even though im buying one from mui thai, i would also like to fully understand how everything is made to work. now if i could only figure out what stabbing the cas means exactly.

 

How can it figure out how to do the timing if you cut teeth out of the CAS? I've always wondered that myself, I can see why it would need less teeth or whatever but how can it do it if the teeth aren't evenly spaced?

 

it's exactly because they aren't evenly spaced that it can figure out the timing. The missing tooth is used to sync the tooth count...when it crosses the missing tooth, it resets the count to 0, and then each tooth after that the megasquirt counts up. It uses whatever you set as your trigger teeth for actually calculating when to fire the spark plugs... The only difference from using the stock CAS is that you can't use tooth number 12 because it's cut out.

 

edit: DOh! wrong thread!

 

It doesn't matter. What matters is what you're more comfortable with. They are 2 different means to the same end, providing a sync for the code so it can count teeth from a known shaft position.

-Mike, running a de-toothed CAS.

 

ahhh I see now.

Thanks

 

i had another question. i just got home to finally finish this up. i've been following this diagram for the wiring harness. it's on assy guide for v3. my question is above it was stated to "Wire the Ne+ wire to the "tach" pin on the MS, and wire Ne- to one of the MS's ground pins"

by looking at the pic below, i just want to verify that the "tach" pin is pin 24 and that a negative pin was pin 7. i'm using a MS1v3



Also just a random question, how am i suppose to keep my stock tach working along with the rest ofhe stock gauges? anything special that i'll need to do? i have an 84 gsl-se with a n/a s4 going turboed.

 

13B4port,

Connect as shown, and you should be fine. I'm running EDIS-based ignition, so I'm using the tach pin on the ignition module. For your tach, try connecting to the -ve terminal on the leading coil. That should trigger the stock tach the same way as the original leading coil with dizzy.

You'll love the turbo 1st gen. I just got my SA out last week. It's now running an S4 6-port with S5 turbo, FMIC, 2-1/2" exhaust with twin Magnaflow mufflers. It's running very nicely, but the stock clutch is not up to the task. Hard accel in higher gears results in some slippage as engine speed passes 5500 rpm. I've got an ACT street strip combo on order now to address that issue. You may want to consider similar if you haven't already made plans on that front.

 

yea i gota pull my tranny now. i went out last night with a few other fellow 7 owers and a ew s14 owners and did some drifting. I pushed my car a little hard, impressed a few people that a 84 se with a 88n/a motor running on the original 1st gen ecu could do some of the things i was doing. I called it quits when my tranny started to whine. i have a bad bearing on the counter shaft. got a nasty whine in all gears except 4th. should be to hard to get the bearings replaced. i'll tear it down and take the covers to a shop and have them press in new bearings for me. I have a stock clutch being rebuild and upgraded by a local shop. cost about $150 for the preasure plate and clutch disk. When it's done though.... it's gona still have the same feel and drivability as a stock clutch but it's gona hold a lot more. They promised it would hold up for 400hp, if it doesn't or wears out too soon, it's free replacment and installation. now if i could just get the local tranny shop to put a new crush bearing in my lsd and realign the ring and pinion so that dumb whine stops, i'll be in business.

How much boost are you running?

 

Stock S5 wastegate, with no boost controller at this point. It holds at 5-6 psi initially, then creeps to 8psi by 5500 rpm.

 

a few more questions. should i wire the grounds for the sensors back to the ecu? or should wire all the grounds to the car? Also anyone wanna share their MT file (.msq i think). I'm running something a little different and a base would be realy helpful. i'm runing a s4 n/a block, s5 turbo and manifolds with 4 680cc injectors.

thanks again guys.

 

I usually wire the sensor grounds back to the MS, and the MS grounds to the engine.

 

what pins on the MS should i wire the sensors grounds to?

 

preferably wire them all to pin 19.