TKX magnetic VSS Calibration

hotpony

Founding Member
Feb 26, 1999
922
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38
Lee County, KY
I swapped to a TKX this last week on my 96 Cobra and I tried plugging directly into the magnetic pickup VSS that comes on the transmission since it was the same connector. I didn't think it'd be accurate but it's reading like 120mph at 35 actual so is there a way to calibrate off the magnetic VSS or should I swap in the gear driven VSS that was on my T45? I swapped gears from 3.31, to 3.73's also so either way I have to calibrate. Would love to just use the one that came with the TKX and yes I do have a tune but it's a chip so I'd have to get back out to the dyno tuner in order to have it changed.

Will a speed cal work for this or is the magnetic pickup too far out of range?
 
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I used one of these on my 98 GT to correct the speedo after a gear install. It's just a ratio changer, so you should be able to dial it in to correct it. I did have to add a 1mF cap so the ecm would see the signal correctly. The guys there are awesome and have excellent customer service. They helped me troubleshoot the issue and get it working correctly.
I mounted it inline with the grey wire going from the sensor to the ECM, with keyed power from the radio supply.
I used .85 as a correction factor on mine. But it is widely adjustable.

 
Wow nice man! I ordered one from Abbott and it's supposed to be good. I talked to them on the phone about the Electeonic Ratio Adapter (ERA) with the extended range. He said it would easily adjust to the OSS because it's a starting point of a divisor by 4, then some fine tuning I'm sure but it was $180! Oh well, long as it works I'll be happy.
 
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I got the Abbott ERA installed yesterday, wired it into the stereo ignition power and ground and split the grey/black wire from the vss harness. I configured the ERA to a divisor of 6 and it's pretty close, maybe 7-8 mph slow. I can really fine tune it if I want but I think it's good enough.

Downside is it's $180! But main reason I didn't go with the mechanical VSS was because the hardware for the cross member support (Stifflers) and the TKX adapter kit hardware is pretty long so I was going to have to cut off some of the bolt that goes up through the trans to get the sensor to fit in there. Also I think it's a lot cleaner.

Note: I have 3.73 gears and 18 inch wheels with 35 series tires.
 
I have a similar setup with zero issues. I have boxes full of the Dallas SpeedCals, so to me I could have gone either way. I like mine being dead on, which you can with the Abbott and SpeedCal or even the driven gear, I just wanted the original setup in the car.

I'm running 3.73s and 18's as well.
 
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I have a similar setup with zero issues. I have boxes full of the Dallas SpeedCals, so to me I could have gone either way. I like mine being dead on, which you can with the Abbott and SpeedCal or even the driven gear, I just wanted the original setup in the car.

I'm running 3.73s and 18's as well.
Pm me if you want to sell a speedcal