Hi Guys,

I was doing a bit of tuning and adjusting on my car yesterday (changed power valve and main jets) and decided to check the RPM's on my old tuning meter against the Factory Tacho in the dash, interesting results; 2000 on Tacho showed 1800 on meter, 3250 on Tacho showed about 2800 on the meter. I can only assume that at 6000-7000 it is about a grand out.

I had always wondered about this as the 327 runs off the end of the guage if you keep it to the boards and let it change up by itself, also couldn't make the revs per km match up with what it calculates to, based on tyre size and gearing etc.

Just wondering if anyone was running an aftermarket Tacho, and what difference they had noticed ?

Ta, Craig.

 

Factory tachs are notoriously inaccurate. An aftermarket tach is a good investment on any 3rd gen that's going to get wrung-out from time to time.

Comparing the tach to what the ECM shows for RPM on a scan tool is another good way to double-check.

 

My tach shows about 200rpm lower at idle than my scanner.

 

"ECM shows for RPM on a scan tool..." FYI, no computer, I think the only electronics in my car are the HEI and the Stereo, LOL.
Seriously, thanks for the Input guys not really keen on a great big aftermarket Tach' standing out (all the kids in their Honda's and Hyundai's have them!), but might have to consider one if I ever get to the track, wonder if I could just add a shift light by itself.
Craig.