I traded out my tach and and (115) speedo for a 145 speedo and 5500rpm redline tach.
Anyway, I hooked up my laptop to the computer and my original tach was off by 150RPMs which was alright....put this one in and it is off by 400RPMs. I don't like having to subtract 400 everytime i look at the Tach. So is there anyway to adjust the tach (ohm reading or something)?
Thanks,
MM

 

Not that I know of. The factory tachs are known to be off. I bought an aftermarket one.

 

Ok....another question i just thought of.....does the speedo affect the tach reading? As of right now, My speedo is off by 15 or so MPH at highway speed because of gear swap...if the speedo is corrected, will this remedy the tach?

 

No, speedo doesn't affect the tach. The tach is connected to the distributor.