jmark06

Yes I did swap the pulley over and I did remove the external regulator when doing the swap. I agree it's probably fried now because it was fine before I touched those leads together. I'll try to find a source for the rebuild parts.

Any ideas on this one?

I swapped a 90 amp maxima alternator into my '77 280z and did the maxifuse upgrade at the same time. After I got all the wiring sorted out it worked well...around 13v at idle and 14.5 under throttle, for months. I was working on it the other day when I accidentally touched the +coming out of the alternator to the ground and there was a big spark. Since then it hasn't worked right. It seems to hold around 12.5v but dosen't change any with throttle. When I disconnect it the voltage drops down around 12.1v so it's definitely doing something. If I pull it off the battery and check the output it's around 18v. I went and had it tested at Advance Auto and it checked OK. Does this sound like a messed up voltage regulator and if so what can I do to fix it?

Well the pressure rises a little before it starts coughing and then drops when it coughs but hen shoots back up. The inj banks light up on the stim board so it seems like everything is working properly. I'm guessing that if Q1 and Q5 were fried that the injectors wouldn't fire at all. Is there anything in the computer that could cause this, no settings have changed. If the VB921 was fried it wouldn't fire at all right? I checked cylinder 1 with a timing light again and it seemed sparatic when I opened the throttle up some, but I don't know if that was caused by the coughing or the spark itself. Could the 30 year old coil be the problem? It was running perfectly one minute and then terribly the next. I could be wrong but it seems to be getting worse, like even the idle struggles a little and now even 800 rpms coughs badly. The AFR is showing 16 at adle and 19+ with any throttle at all.

I've serached some, but I'm in a hruuy cause my car is broken down in a neighborhood about 15 min away and I need to get it out of there today if possible. I was driving my 280z (I rebuilt an 82 turbo engine, using MS1 v3.0, stock dizzy, firing with internal VB... and stock coil, supra 440cc injectors, walb 255 fuel pump, aeromotive FPR, JSK O-ring rail) and it was runing fine for about 30 min. I got on it a little a couple of times only to about 4 or 5 psi boost and it did fine. Then one time when I got on it some, maybe 2 or 3 psi it starting choking when I slowed down. I pulled over and it idled fine. Whenever I got over about 1000 rpm though it started coughing bad. I had to get someone to come pick me up cause it was dark and I had no tools or computer. Today I went back and hooked my computer up to it. Still cranks OK and idles fine at 600-700 rpms. But when I open the throttle up, even slowly it coughs badly after about 1000rpms and never gets better. It runs into the 18+ air:fuel. I checked both the pre and post pump fuel filters and they seem fine. The pump seems to be working OK, but I haven't really tested it. I have constant 38 psi pressure at idle but when it starts to cough the pressure drops off some. I checked the spark with a timing light and everything looked fine. I just don't know what could have happened to cause this all of a sudden. I pulled each plug wire individually and it sounded like all 6 cylinders are firing at least at idle. Nothing seems weird with the megasquirt except Q1 and Q5 are not bolted down to the heat sink. They don't appear to be fried though, but maybe I can't see it. I guess they weren't bolted down before, but I really don't remember, I don;t knwo how they would have just popped up though if they were. My req fuel is 7.1, inj opening time 1.1, PWM current 20%, and PWM time threshold 1.1. None of these settings have changed since it was running fine. Any ideas?

My starter was no good and I replaced it so the car turns over no problem now. I eventually decided that my CAS was the problem so I bought a new one. STILL NO TACH SIGNAL on MS. I checked and I have 12V going to the red wire, the black wire is grounded, and the signal wire is connected to the white wire. I have the 1k res wired into the MS board as per DIYautotune.com. I pulled the distributor out and wired the 12v and ground wires up and put a meter on the output spade. No voltage when I turn the shaft. Maybe I somehow got the wiring mixed up when I was rewiring everything. Does anyone know which spade is what on the CAS itself, not referencing the old wiring. I'm running out of ideas. The tach works fine with the stim board hooked up.

Yes I have 12 volts to the distributor during cranking. I've checked all the wiring from the distributor back and it's all fine. Now I can't get the engine to turn over, I think it's because my battery is too dead to turn the starter. It turned over on the first try after I charged the battery for a couple of hours, but hasn't since then. On that first try though the tach in megasquirt didn't work at all (or my car tach for that matter). I want to check the signal wire and see if it's gettin gany voltage during cranking to make sure the CAS is working correctly. If it is, which I will find out tomorrow, then I must have a problem with the megasquirt I'm guessing. The car was running fine with the old computer so my thought was that the CAS was OK. I just though it would be some kind of loose wire issue or something since it works sometimes and others it doesn't. But all of the wiring checks out when I test it with my multimeter. My hands are bleeding and I'm cold and frustrated, any suggestions?

Any suggestions? should it be 1k or 330 ohm? I think that the capacitor is OK but I'll replace it anyway. I'm really frustrated with it.

I tried to set my timing before cranking my engine and had very sparatic tach signal the few times that I got one. I'm using an 82 dizzy to give the signal, wired according to DIYautotune. I got a signal sometimes when I tried to turn the engine (fuel pump fuse pulled) but usually nothing and sometimes when it did show something on the MS tach it would jump around and then go off. I rewired all the areas from the dizzy back that still had some of the old wiring and still have the same problem. When I hook it to the stim the tach seems to work fine. I went back to make sure everything was wired properly inside the MS box and noticed on the DIY website that the instructions say to use a 330 ohm resistor but the drawing shows a 1k resistor. I'm using a 330 ohm, is that a problem? It looks like my capacitor at C11 is fried so I need to replace it, but I don't know if that will fix the problem. I think I have everything from a software side set up correctly. MSns is set and only LED 17 set to Spark output. Spark is set to inverted YES and cranking RPMs set to 300. Voltage is good in crank and run. Any ideas? Like I said it seems to sometimes work, but most of the time nothing, I'm hoping the capacitor is the problem or maybe I'm using the wrong resistor.

Aftermarket O-ring with supra 440cc injectors

Is there any reason I shouldn't run my feed line from behind the engine along the fuel rail, then turn 180 back into the rail at the front of the engine? Will it heat up the fuel or anything that I don't want? I just think it might look good but I don't want to do it that way if there is a better way. I'm running stainless braided hose.

Thanks Pop N Wood, I'm looking for about 300 hp when I finish using MS extra and supra 440cc injectors. I beleive the outlet on the tank is around 7/16" but I was going to come off of there straight to 6 AN hose then to a filter with 6 AN inlet and outlet. Will that be OK for my setup or do I need to go 8 AN before the pump?

I'm getting ready to plumb up my turbo engine in my 77 280z and need a couple of questions answered. I've searched and figured most of it out, but want to make sure. I want to use 6 AN braided from the tank, to filter, to pump, to filter, to rail, to regulator, to return, to tank. I measured the tubes coming out of my tank the the top one is bigger than the bottom one. I figured the bottom would be the outlet (to the pump) but it's smaller, I think 5/16". The top is closer to 3/8" or 7/16". So which should I use as the outlet? Secondly, do the AN to tubing compression fittings from Earl's work well? And finally, what tools will I need to put everything together, I've not worked with AN fittings and hose very much? Thanks for your input.

I'm getting ready to plumb up my turbo engine in my 77 280z and need a couple of questions answered. I've searched and figured most of it out, but want to make sure. I want to use 6 AN braided from the tank, to filter, to pump, to filter, to rail, to regulator, to return, to tank. I measured the tubes coming out of my tank the the top one is bigger than the bottom one. I figured the bottom would be the outlet (to the pump) but it's smaller, I think 5/16". The top is closer to 3/8" or 7/16". So which should I use as the outlet? Secondly, do the AN to tubing compression fittings from Earl's work well? And finally, what tools will I need to put everything together, I've not worked with AN fittings and hose very much? Thanks for your input.

Carjway, were you able to fit your injector electical connections on with the injectors cocked sideways like that?