1995 V6 To V8 Gauges

[Tommy Nikkel]

I bought a 1995 mustang that had a 5.0 swap already done. The speedometer is already about 6-7mph off. I plan on buying these gauges. I know installing them should be self explanatory but how much would the speedometer be off and how would I fix that? Also would the new tach be the correct one for red lining or the old one? Would I have to buy a whole new GT gauge cluster?

 

[Chythar]

You know, if you buy white LED bulbs for the factory cluster, the color changes from white to blue? No need to change the gauge faces, unless you want to change their look along with the color. You also have to pull off the needles on the gauges to install those new faces, and you risk mis-aligning them.

As far as the gauges, the speedometer & tachometer gauges pull out of the cluster housing, so you could replace them separately. Not sure if that would be all you need. Personally, I'd buy a new GT cluster and be done with it. The GT cluster is a simple swap, you just unbolt the V6 cluster and plug in the Gt one. No wiring, no cutting, just a straight swap.

 

[jozsefsz]

I don't know much about the behavior of the gauges when swapped - only commenting here to mention those gauge-faces don't require the removal of the needles so it's a pretty easy change. I don't know if the gauges will then be better-calibrated to the tach / speedo or not. Swapping to a GT cluster won't necessarily correct your speedometer calibration.

For the speedo it would seem the transmission was swapped out, but the rear was left with the v6 ratio? Find out what ratio the rear in the car they were pulled from had, and the rear in your current vehicle has. You can replace the VSS (speedo) gear from your old transmission to the new one and that should fix your calibration. Unless it's off because of tire-size.

You can buy a calibration unit (like this http://www.americanmuscle.com/ford-speedo-tool-9410.html) or swap the VSS gear to the correct one. You need to know how many teeth are on the one now and what the mph % error is. If the speedometer is reading high by 10% and the gear is 20 tooth then you need to change it by 10% or 2 teeth -- to slow it down you would use a 22 tooth gear.

If you want to try to keep the tachometer too, getting an independent read on the RPM (using an external gauge at the coil) can help you determine which of the two gauge configurations is correct. You'll want to stick with the v8 redline for how far you should rev if that was your question.