01Racing

The 1990 RX-7 manual shows the cars either had "engine speed sensing power steering" or "electronically controlled power steering". Does anyone know which system applied to which models? eg. speed sensing GX, GXL etc.

Syritis

iTrader: (2)

S4 have RPM sensitive power steering
S5 have Road speed sensitive power steering

Black91n/a

I do beleive the TII's got the speed sensing PS and the NA cars got the engine speed sensing PS (= "electronically controlled power steering") for the S5, and all S4's got the speed sensing PS.

01Racing

Does anyone know for sure??

Black91n/a

I just looked in the FSM and id doesn't give any clues, BUT there's an easy way to tell them apart visually. The speed sensin has two lines coming out of the back of the pump (3 total), and the engine sensing has only one line there (2 total).

Also, according to the 1990 sales brochure, the Turbo got the vehicle sensing, while everything else got the engine sensing.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/specifications-what-did-2nd-generation-rx-7-come-w-options-standard-features-249616/

It's about halfway down.

01Racing

Thank you so much that is exactly the information that I needed!

Syritis

iTrader: (2)

my 87 Tii has RPM sensitive. (terrible idea) but black91 is correct about the lines, RPM will have 3 lines on the P/S pump and the rack. road speed have only 2. i'm still very sure it's the difference between S4 and S5

fastrx791

I have a 89' GXL that has the Electronically controlled power steering and two 91's (NA as well but not GXL) that have the Engine Speed Sensing. But what is the benefit of having the Electronically controlled PS and is it worth Swapping it from my parts car? Also, does anyone know how difficult it is to switch over the electronic suspension?

Terrh

iTrader: (7)

S4 TII's for sure without a doubt have vehicle speed sensing.

Disconnect the speedo cable and go drive around. be amazed at the wonky power steering feel.

23Racer

All I know is that by 30 mph neither system provides any hydraulic assist. When I pulled my power steering off of my RX7, I noticed absolutely no difference on-track. The only thing I noticed was that it was a lot harder to muscle around while driving around in the pits.

Al, just pump some more iron............LOL.

The other thing to be concerned about is power steering pump cavitation. When I raced my car with the P/S for the first 2 years, I always needed to refill the unit after every race. As well the mess from pumping out the fluid was sometimes pretty special if there was oil dry down.

Eric