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My Formula was a factory TBI car so it has the 120 speedo with 6k tach. Is it possible to switch the motor and stepper gears from the 120 mph speedo over to a 140 speedo with the 8k tach so that my mileage is accurate on the new cluster? With the LS1, the 6k tach is not going to cut it.
My Formula was a factory TBI car so it has the 120 speedo with 6k tach. Is it possible to switch the motor and stepper gears from the 120 mph speedo over to a 140 speedo with the 8k tach so that my mileage is accurate on the new cluster? With the LS1, the 6k tach is not going to cut it.
Assume you are using a 411 for your LS1... you can program the 411 to correctly drive directly the the speedo and tach. I didn't double check but likely the 120 and 140 mph speedos use the same ppm input. For tachs as long as you stick with same type ie V8 tach again it will drop right in.
ok sorry, i now understand what you are trying to do.
While i haven't directly tried what you are doing, I have repaired these type of speedometers as it is a common problem for the gear that the motor drives on the odometer to break over time. it appears that this gear is also different between US miles and rest of the world KM. this would indicate that the motor drive portion of the circuit board is the same and the increment of count on the odometer is in final regulation by the ratio of the gear that interfaces to the motor and the motor's gear, with the motor gear being the same, just the gear on the odometer being different
therefore if i was trying to do what you are doing, what i would do is keep everything from the 140 mph speedo other than the actual odometer portion (ie keep the circuit board, speedo needle drive, odometer motor, etc, etc from the 140) and reassemble it.
if you look there is a thread about repairing this odometer gear. i show how i do it and also a test circuit i made up using a dakota digital interface box in test mode to show it works. you could try this as well (it also insures the speedo needle is back in the exact right position). see the link below- (also as these gears are known to fail since you have yours apart you may want to do this also if you haven't already)
I swapped out the whole gage pod in my Firebird and it requires no special calibration. I set the odometer to same value as old. The 140 mph speedo is a disappointment though. Harder to read and not nearly as accurate through the range as my original 120 mph speedo. The only reason I changed it is because I pin the speedo in the 1/4 mile. Wasn't really worth it, might go back to my original speedometer.
I swapped out the whole gage pod in my Firebird and it requires no special calibration. I set the odometer to same value as old. The 140 mph speedo is a disappointment though. Harder to read and not nearly as accurate through the range as my original 120 mph speedo. The only reason I changed it is because I pin the speedo in the 1/4 mile. Wasn't really worth it, might go back to my original speedometer.
By set I assume you mean rolled back? I currently have the 85 mph one and even though my car probably won't see over 100 for a long time, I hate how filled the gauge is by markings. I'm not sure how unique these are but the one I pulled doesn't have km/h markings, just mp/h. I feel that the 140 (or even 120) makes the gauges feel more "modern" but that's just my own opinion.
Rolled forward actually, but yeah you got the idea. My car has more miles than any of the gauge pods I bought. I keep picking up low mileage gage pods from people but haven't found one yet as nice as my original. It's really annoying. Apparently my **** really is better than other people's ****.
Rolled forward actually, but yeah you got the idea. My car has more miles than any of the gauge pods I bought. I keep picking up low mileage gage pods from people but haven't found one yet as nice as my original. It's really annoying. Apparently my **** really is better than other people's ****.
Looking at your build thread, I would not doubt it. Your car is unbelievably clean. The car I pulled the speedo out of was an '86 WS6, TPI, in bright red with a black interior when it came out of the factory. 150,000 miles later it lay in a junkyard, rattle canned black and being pulled apart by people like me. Then again I can't say it was in too rough shape, the interior looked very clean and the center console worked unlike my '86 and honestly, if I hadn't used the rest of my money buying that speedo, I would have taken the console home with me too.
I think you'd really like the 120 mph speedo. It has nice scale and markings, and it's a lot less expensive. And you might have better luck finding a really good one because V6 owners sometimes take care of their cars better than V8 owners.
I think you'd really like the 120 mph speedo. It has nice scale and markings, and it's a lot less expensive. And you might have better luck finding a really good one because V6 owners sometimes take care of their cars better than V8 owners.
The 140 I picked up is in fairly decent condition, just needs to be cleaned. The lack of km/h is somewhat cool. The only info I can find is that they produced them in a weird time frame in '86 when they switched away from the mandatory 85 mph clusters. Not sure if that makes it anymore collectible or something.
I've had a minor setback on my project. Tested positive for Covid last Friday and I've been getting my butt kicked since. Maybe in a couple weeks or so when I get my strength/motivation back I'll get back on it.
I've had a minor setback on my project. Tested positive for Covid last Friday and I've been getting my butt kicked since. Maybe in a couple weeks or so when I get my strength/motivation back I'll get back on it.
Hope you have a speedy recovery! I actually ended up going through with it and swapping the odometer from my old 85 cluster into the new (well not so new) 140 cluster. The only issue I have now is that the speedometer is not recognizing when I am slowing down, as in I get to 30 mph and stays there. Only when I come to a stop does the needle drop back down to the bottom. I may switch the connector from the rear of the gauge with the one from my old gauge and see if that is the issue. In regards to the odometer I did not notice any issue with it so I do not think you will have any issue swapping your out. If anything else is to stop working I will report back with more info.
I've had a minor setback on my project. Tested positive for Covid last Friday and I've been getting my butt kicked since. Maybe in a couple weeks or so when I get my strength/motivation back I'll get back on it.
Wishing you a speedy recovery with no lingering after effects.
I know this is a 3 year old post, but I have an 86' T/A with a 85 mph speedo. I bought a dash with instrument cluster from an 87 GTA with a 120 mph cluster. I would like to switch out but, unsure if any additional work will be needed. I will need to roll the odometer forward as this cluster has half the miles on it as my car (something else I do not know how to do).
I no longer have my car but if I remeber right (it has been a long time) it was a simple swap on the overall unit. What I did do was pull both apart and swap the odometers so that my new gauge cluster matched the mileage from my old one and it wasn't that difficult.
I no longer have my car but if I remeber right (it has been a long time) it was a simple swap on the overall unit. What I did do was pull both apart and swap the odometers so that my new gauge cluster matched the mileage from my old one and it wasn't that difficult.
