I believe that I need a rack and pinion. I noticed that some have a sensor in them and some do not.

Can someone show me, or tell me how to determine which model I may need?

 

Power steering I assume? Try looking in the FSM's at the s4 and s5 ones, and see if you can find the one that matches yours.

 

there are 3 LHD FC racks

1. FB01, manual. 20?:1 ratio. 86-88

2. FB15/FB44/FB78 power. 15:1. 86-88 all, 89-91 upper models. this is the first variable power assist rack for any car ever, can be ID'ed by the 3rd pressure line

3. FC01, power. 17:1 89-91 base models. normal 2 line rack.

 

Would the 89 vert have a 2 or 3. I’m not sure weather it’s considered base model or not

 

89 Vert same system as the Turbo and GXL, speed sensing.

 

is this a for sure thing or could it vary. Wanna be 100% sure

 

According to my original 1990 Mazda RX-7 sales brochure (yes, I still have it) copied verbatim:
Steering: Rack-and-pinion type.
Engine-speed-sensing variable power assist (GTU, GXL, Convertible)
Vehicle-speed-sensing variable power assist (Turbo)
Steering ratio: 17.4:1 (GTU, GXL, Convertible); 15.2:1 (Turbo)
Steering wheel turns, lock-to-lock:22 Turning circle, curb-to-curb: 32.2 feet

For the limited edition GTUs trim line, the Turbo specs apply to its steering.

These specifications most likely apply to all Series-5 RX-7's.
I have no information on the Series-4 RX-7's. All that I can say with certainty is that the 1986 Sport model came with manual steering. (I once owned one, which was purchased new.)

 

so if I have an s5 vert, I’m good to pull the trigger on a 3 port?

 

Here are the Mazda p/n's for turbo and non-turbo models (see 32-110 in attachments):
PS Rack Engine Speed Sensing p/n FC01-32-110A
PS Rack Vehicle Speed Sensing p/n FB78-32-110C

I don't recall which of the above racks are either 2 or 3 ports. Unfortunately, I cannot find any photos or my car's rack. If your PS rack is the stock rack, than you might be able to determine how many ports is has by Googling the appropriate p/n to find a photo of it. Good luck.

 

There may be a difference between '89 and '90 vert racks.

"The 1989 convertible has the fast 15:2 rack with vehicle speed sensing power steering standard. They went to the cheaper engine speed sensing rack in 90-91."
Post #21 (https://www.rx7club.com/2nd-generati...s-mods-607260/)

Probably best to checkout your car's rack before buying.

 

89 vert will be a 3 line, and 91 is probably 1, and 1990 can go either way

 

Following has all the info by year:
https://www.rx7club.com/2nd-generati...atures-642372/