Ecm delete?

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TagAllen

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Even if the computer does not control the trans how would his speedometer work?
 

89RCLB

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The early SS454 trucks had a TH400 but I'm not sure how the speedo/odo got it's signal from the trans. @someotherguy may know.
 

PlayingWithTBI

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Even if the computer does not control the trans how would his speedometer work?
The earlier TBIs used a DRAC (Digital Ratio Adapter Controller) or VSSB (Vehicle Speed Sensor Buffer) that takes the 2000 PPM (Pulses Per Mile) signal from the VSS, converts it to a digital input and sends it to the ECM, speedometer, and cruise control module. The newer trucks' PCM converted the signal and sent it to the speedometer and cruise control. So, you don't necessarily need an ECM to have a functional speedometer.
 

Erik the Awful

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I switched to a Holley Sniper. My TPS is not connected to the factory computer. My TCC and distributor work just fine; I have lockup and advance. The factory computer is still in place for now.
 

DamHoodlum

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I deleted my ECM all together, When I went to carb (Which a lot of people here don't approve of) my transmission guy took the 700R tail shaft assembly and put it on a Turbo 350 that mounted directly where the 700 was, I used the same speedometer connection, driveshaft, transmission mount, I didn't even have to move my crossmember, I did use a Transmission Specialties TH350 2500 stall converter. My speedometer works of the DRAC and still works as intended (My truck is a 1989 model) If you want overdrive you can make 700R withstand that amount of power relatively easy with minimal wiring to lockup the converter if you choose, or use a non lockup converter with the overdrive.. There are a lot of options to choose from
 

retorq

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>my transmission guy took the 700R tail shaft assembly and put it on a Turbo 350 that mounted directly where the 700 was

That's called a long tail 350. They had three different tail housings 3inch, 6inch and 9inch. I got a 350 for my FBody years ago from a truck guy. Turns out it was the same dimensions as the 700R4 so I was able to use the fox body AL driveshaft with conversion joints. Then all these years later here I am, I have a fox body so I converted back and used that ....
 
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