GREAT thread...does anyone know if there is a diff between CFI tachs ol skool coil fired tachs ? I have a 93 LX that had a 4cyl n it but I put a 84 GT 2.3T n WC T5 in it while using a repinned MERKUR XR4Ti stand alone harness. It runs great but the tach won't register until about 2600 then it jumps up to where it pegs out sometimes n stays pegged until I blip the throttle again but it never registers the r.p.m accurately or just stays at 0???
Fox 4 Cylinder to V8 Tach
- Thread starter 93CalypsoConvert
- Start date
foxannne
Member
Stumbled on this thread hoping to get my 4cyl tach working with the v8 swap. Car is a '90 and the spare tach I have is also a '90. Both ex 4cyl cars. What I find strange is both tach boards are completely different from the boards I've seen you guys posting here. Am I missing something?
And yes I'm aware I could run aftermarket tach etc but I'd rather this one work if possible lol
And yes I'm aware I could run aftermarket tach etc but I'd rather this one work if possible lol
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Look for a part nimber, the first thee characters are year/model, set of four I believe are engineering numbers, these seven characters should match both parts, the one or two letters ie: A or AA or AB at the end, AA and AB mean it's an updated version of the A
I believe this to be fairly accurate.
But I may be wrong......
I believe this to be fairly accurate.
But I may be wrong......
One is an E8ZF and the other F0ZF, so a 1988 and 1990, but both are identical boards? There is also a tag on the back side stating install date I'm assuming. One in May of '89 and October of '89
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What does the guage face look like?
E8 is a 1988 engineering number, but doesn’t necessarily mean it was made in 1988. Given the may ‘89 sticker, my guess is one is a late ‘89 model year tach (so 87-89) and the Oct of ‘89 is an early 1990 tach (90-93) give that the model year changeover was around Sept.
E8 is a 1988 engineering number, but doesn’t necessarily mean it was made in 1988. Given the may ‘89 sticker, my guess is one is a late ‘89 model year tach (so 87-89) and the Oct of ‘89 is an early 1990 tach (90-93) give that the model year changeover was around Sept.
This makes sense because one has the notch out of the corner to clear airbag column for 90 and up cars, and the other is straight across, a definite 89 car.
I traced the circuitry on the board to compare where the resistor was changed in the other boards and I think I found it. Will try and change it out tomorrow and test.
I'll post my findings after I test
That's why my video above is specific to 87-89. The tech changed slightly in 1990 and since I didn't have any to play with, i was unable to get an info on what to change
Success! Like noted above in this thread it's the resistor wired next to the adjustable potentiometer pot. Changed out the original 64.9k to a 22k ohm. And with a very very last minute before work test it seems to be dead on without comparing to another tach. (Based on what I know the car idles at etc)
