Page 1 of 1

ms3x help/ thoughts

Posted: Aug 01, 2012 1:58 AM
by bornagain
hey buys been a while... so busy with work, baseball, fixing the car over and over again. but im getting to wits end here.

so the build....

m30b32, flipped tb, borg warner s366 turbo, 79lb/hr injectors, o-ringed the block, full rebuild, 255lph in tank with 255 inline. running batch injection right now, with wasted on one of diys 6 cyl coil packs.running 7lb boost. Wired the vr with 15k ohm resistor.

the issue is at around 4900 rpm it appears that i have some sort of break up but it doesnt appear to be tach drop out(doesnt drop off it just fluctuates) and it doesnt seem to be spark blow out(no machine gun). i have looked for other discrepancies and i found for some reason my tps tappered of on higher gear full throttle runs. so i didsconnected that to see if that helped, i pulled the vr wire out of the loom to see if that helped. but its still there. any ideas would be much appreciated.

anymore info you need let me know.

Posted: Aug 01, 2012 10:41 PM
by marc79euro645
Have you tried tuning the pots (r51,r56, iirc)?
If your pulsewidths don't flutter, it's probably the vr signal.
good luck
marc

Posted: Aug 02, 2012 3:17 AM
by bornagain
thanks yeah i have tuned the pots but i may try setting them again. i went to run a sync error log tonight but i accidentally ran a comp log, and by the time i had realized it, i was sitting on the side of the road with a broken axle. apparently i have too much torque.

Posted: Aug 02, 2012 11:10 PM
by marc79euro645
Bummer, that's the fun of hot rodding a car.
first you make more power,then you chase it all the way to the back tires,clutch,guibo,shafts...
good luck
marc

Posted: Aug 02, 2012 11:19 PM
by winfred
i had a bump in that rpm range running about the same boost with my MSII powered m20 and it turned out to be too much fuel, it took a while to figure out but what finally broke it for me was the installation of a msd unit made it a little better. 79# sticks, that much pump and only 7# of boost seems like a ton of fuel potential with not that much air to burn with it, i know its apples to oranges to compare mine (2.8 m20 with a supercharger and 34# injectors) to yours (3.3 with a turbo) but...

Posted: Aug 03, 2012 5:10 AM
by bornagain
no i appreciate the input, the 79# injectors arent to run the car at only 7 psi. i just turned the boost down to this level till i can figure out the issue. then i will put the second wastegate spring back in (14 psi with both springs) then i will start tuning the water meth and boost controller. ;) but till i get this figured im not risking the motor.

two things to add to the question at hand but didnt really change things.. a. the tps seems to bleed off signal at high load(disconnected that and no change) and b. the ms3x unit seemed to not be sencing the right voltage so i chased that down and i found a loss of voltage due to resistance in the wire so i change that out but that didnt change it either. and finally i added a relay for just the coil pack to isolate that and that didnt seem to change it either.

i did a couple of runs tonight with the sync logger on and nothing came up either.

Re: ms3x help/ thoughts

Posted: Nov 29, 2017 1:50 PM
by bornagain
This is way over due but i forgot to post the fix about 5 years ago when i found it..... jumper for crank signal was on normal polarity on the ms3x board diy sent me. Set it on inverted and it was fixed