Apparently Ford did allow for adjustibility of the stock Tach. They just either didn't do it well, or chose to leave it off in the upper RPM's.
On the backside of the tach, there are pots that allow you to adjust. 87-88 have 1 pot, while 89+ have two pots....high range and low range.
Basically you need a frequency generator that can generate in the 33.3hz to 466.6hz frequency range. Many people do not have this peice of equipment, but some in technical feilds may.
If you have it, you can generate a signal and then use the pots to adjust your tach. You can actually get it accurate enough where there is no need for an autometer tach.
Guess i'll start tracking down an 89+ tach (greater adjustability) and find the equipment needed to calibrate it and swap it in! I HATE the 5" autometer tachs, and have a small shift light i want to hide in a vent...but an accurate tach would be nice.
There is a good thread on this on corral.net if you want to look for it. I can't really link it, but the info is too good to not pass on to some here.
On the backside of the tach, there are pots that allow you to adjust. 87-88 have 1 pot, while 89+ have two pots....high range and low range.
Basically you need a frequency generator that can generate in the 33.3hz to 466.6hz frequency range. Many people do not have this peice of equipment, but some in technical feilds may.
If you have it, you can generate a signal and then use the pots to adjust your tach. You can actually get it accurate enough where there is no need for an autometer tach.
Guess i'll start tracking down an 89+ tach (greater adjustability) and find the equipment needed to calibrate it and swap it in! I HATE the 5" autometer tachs, and have a small shift light i want to hide in a vent...but an accurate tach would be nice.
There is a good thread on this on corral.net if you want to look for it. I can't really link it, but the info is too good to not pass on to some here.