I'm trying to simulate a VR no pullup tach signal from my JimStim for an LS1 (LM7 5.3L). I have it setup to read 60-2 on the trigger wheel now (in the picture it was not set). Attached is a pic.
SuperHiRes http://dl.dropbox.com/u/249320/Photo%20 ... 7%20PM.jpg
but nothing so far seems to give me any signal unless I jumper to allow the 5v pullup (then the tach jumps around wildly) which I don't need (from what I've read).
When simulating a VR signal, you need to use a pull up and I recommend you use a 12V pull up. I don't know where exactly you read that you don't need it because you do. If you could point exactly where you read it in the JimStim documentation, I'll change it to make it clearer. If you read it about the MS board then it's a different issue as the MS board does not need a pull up when reading a VR sensor (usually).
racingmini_mtl wrote:When simulating a VR signal, you need to use a pull up and I recommend you use a 12V pull up. I don't know where exactly you read that you don't need it because you do. If you could point exactly where you read it in the JimStim documentation, I'll change it to make it clearer. If you read it about the MS board then it's a different issue as the MS board does not need a pull up when reading a VR sensor (usually).
Jean
Yeah I read it on the MS board and so that confused me thank you for clearing it up. I just switched it over and now I'm getting a tach signal but its jumping around with huge 2k rpm swings. Its probably something to do with my board at this point / turning r52 / r56 pot
LM7 doesn't use 60-2 though? Or am I misunderstanding the question.
But also, early JimStim's had a very rough approximation of the LS1 pattern (because I didn't know what the real pattern was.)
Well I guess I read this article where it says its 58x http://chevythunder.com/ls1_page_1.htm
"The crankshaft sensor is a 24X (58X on 2004 and later engines) pulse sensor that controls ignition coil firing and injector pulse."
My motor came out of a 06 GMC van but I trust what you say more than what that article says so I'll switch back to spark mode ls1 aka 24x.
Well since the very early version of the stim (i'm running 1.4) doesn't really support the real pattern should I wait to test the tach until I get it wired up to the actual motor?
