rmp sync loss at 5300 only under load.

[oconnor65x]

all i have is a msq of our current tune the datalogs are way to big and wont let me upload them. but i have ms3x v3.47 on a ls2 style ignition system 58x. we have tried everything. at first we couldnt get the thing to rev past 3500. we fixed this with the 1k pull up resistor. next problem is at 5300 rpm only under a load and when coolant temp reaches mid 170's does it break up. but the funny thing is i can dry rev it to 6500 no problem but under a load it datalogs sync loss and rpm dot drops like crazy but rpm signal does not drop. we have then thought it was the popts again and wne tot the manual and it says adjust r56 and r52 counter clockwise 6 turns then turn r56 two turns clockwise. we did this no change at all. im not sure if this is a problem internally of the box or if there is some setting in the box that is doing it under a load only. also we had the pull up resistor next to the starter near the crank sensor so we figured it might be getting to hot as resistance increases with heat. so we moved the resistor up stream put head shielding around it and same problem. so then we thought that because the crank sensor we bought was not an acdelco oem sensor maybe it was bad so today we put a new ac delco sensor and same thing even after adjusting the pots per manual. what gets me is the crank sensor does not know what load is so why does it break up only under a load. we have an 1 wire alternator on it that puts out about 13.5 volts constantly so i doubt its loosing voltage or anything like that. i dont have a tooth logger of these runs but i do have a msq... if there is a way to shorten a datalog so i can post it that would be nice.

[kjones6039]

the datalogs are way to big and wont let me upload them.............................if there is a way to shorten a datalog so i can post it that would be nice.

Have you tried zipping them? Otherwise you can also trim them with MLV.

Ken

[oconnor65x]

any ideas this is really annoying we have tried everything. here are some tooth loggers and sync loss loggers and compsite log.

[kjones6039]

Although I lack any expertise in evaluating the logs you posted, I will say that they appear to indicate some problems. I'm sure one of the experts will come along and offer up some excellent help.

In addition to the tooth logs you posted above, I think a regular data log would be very helpful.

Ken

[Matt Cramer]

I'm seeing extra noise pulses in the composite log - try activating Tach Period Rejection.