Originally Posted by centerforce99
Seriously, your dealing with two different types of transmissions that have slightly different gearing that make the speeds calibrated to the car. If you don't change them out it will be off but who knows by how much. If you want to do the math go for it.
I hear you. But the speedo is electronically controlled and looks for a binary signal from the Vehicle Speed Sensor.
It's essentially a Hall effect sensor that reads from a toothed wheel internal to the transmission, not unlike an ABS sensor.
Since the GSR trans is geared higher, the VSS will be sending out more pulses per second at a given road speed than an LS trans. That's why I'm concerned that the LS gauge cluster will either read significantly faster, or fail to read a signal at all.
I'm a conservative kind of guy when it comes to this stuff. If it only costs 50 or 60 bucks to have an accurate speedo and tach, I'd pay for a used GSR cluster.
My 2¥.
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