Just triple checking. I've got a 91 T5 lined up for my 89 which uses a cable driven speedometer. Am I in for pain here? Is the 91 an electronic speedo? Hoping its a straight plug and play.

 

You might check with tpi parts.net to see if this would do the trick.
https://www.tpiparts.net/inc/sdetail/7587

 

Yes it is straight-up plug & play.

At most, you might have to move the drive gear over from your existing trans to the new one. Look at them... if they're the same color, you don't even have to do that.

 

The 700R4 and the T5 have different speedo senders and drive gears. He will need a speedo "bullet" and the corresponding drive gear to convert from a later speed sensor T5 to a cable drive, no ?

 

Correct: the 700 and T-5 use different stuff.

Somehow it seemed as though he was going from one T-5 to another. Kinda like when I put a 91 or 92 T-5 into my 83. But maybe not.

Regardless, all he'll need is the correct drive and driven gears for his axle ratio (probably 7 & either 19 or 20 depending on tire size), and a "bullet".

https://transmissioncenter.net/shop/...-7-or-9-teeth/
https://transmissioncenter.net/shop/driven-gear/
https://transmissioncenter.net/shop/...-gear-housing/

 

Okay, sorry for the cornfusion. Just to be clear. I am going from an 89 TH700R to a 91 T5. So...I need a bullet and new speedo gears for my 3:42's?

 

Yes.

 

Yes. 83-89 T5 speedo parts bolt right into a 91 F-body T5.
If the drive gear on the mainshaft isn't a 7 tooth (usually purple,) change that out before the trans. goes into the car. The lower geared models (3.08) got a 9 tooth drive gear (usually red.)

 

Ok, so to go from my TH700R driving my 3:42 rear axle, to the T5, all I need speedo-wise is:

1. a "bullet" and
2. a 7-tooth drive gear. It's not the same as the TH700R drive gear, correct? I already have the TH700R setup for the 3:42's.

I have verified that the T5 I am getting is setup for 3.08 rear axle, which means a 9-tooth drive gear.

And

I can reuse my current speedometer driven gear?

 

As far as I know the speedo gears for the 700 are entirely different than the T5 (both drive and driven). I've never taken 700 gears out to verify though.

They are pretty cheap anyway, just add the driven gear when you order the bullet and drive gear ans not have to worry if they are different.

 

T-5 and 700 speedo gears and everything else about it are different. Not interchangeable.

You need the parts in the links I posted.

 

Ok, thanks!