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Russell
May 7th, 2012, 04:22 AM
Hi!

I'm in the midst of doing an 02 LB7 Duramax swap into my 95 Tahoe. I'd like to use the factory cluster, but need to change the tachometer output signal to match them up. I've looked through EFI Live and haven't seen the tachometer adjustment anywhere... Can someone point me in the right direction?
ScarabEpic22
May 7th, 2012, 05:14 AM
I just took a peek at the included 04 LB7 OS that V7.5 comes with on every install, I didnt see them either. I dont know if they were ever included or not, might want to ask THEFERMANATOR what he did as he has an LB7 in his 95/96 Burb.
THEFERMANATOR
May 7th, 2012, 01:06 PM
There is no tachometer adjustments via EFILIVE, and the LB7's output will not drive a regular or alternator type tachometer. If you have a gas engine tach now, I believe you can use an LS1 tach adapter to make it work. I'm using the diesel tach which is driven off the alternator.
Russell
May 7th, 2012, 02:23 PM
There is no tachometer adjustments via EFILIVE, and the LB7's output will not drive a regular or alternator type tachometer. If you have a gas engine tach now, I believe you can use an LS1 tach adapter to make it work. I'm using the diesel tach which is driven off the alternator.

Ah, thats unfortunate! Bit more work to do... My truck was originally a diesel, so it has a diesel tachometer in it already. Hopefully I can just run it off the alternator as before. If not, it won't take much to build a signal conditioner to multiply or divide the signal and convert it to the 12V square wave the tach needs. Just would have been simpler the other way around, lol
THEFERMANATOR
May 8th, 2012, 03:13 AM
Ah, thats unfortunate! Bit more work to do... My truck was originally a diesel, so it has a diesel tachometer in it already. Hopefully I can just run it off the alternator as before. If not, it won't take much to build a signal conditioner to multiply or divide the signal and convert it to the 12V square wave the tach needs. Just would have been simpler the other way around, lol

If yours is a diesel to begin with, simply go down and buy a 4 pin plug for the alternator and hook up the extra wire. The DMAX only uses the center 2 pins of teh alternator plug, but one of the other 2 is a stotor output that will run your tach.