Venturer

Hi
I'm the owner of a 1991 FC Convertible Turbo 2. It mounts Engine Speed Power Steering (ESPS) but it's a Turbo 2!

I would like to know if there are S5 Turbo 2 convertibles produced that mount Electronic controlled power steering (ECPS).

Thank you.

WJM ROTARIES

No there was no electric power steering on the fc RX7s. the first esps on Rxs was on the RX8

Venturer

I don't mean "Electric Power Steering"!

On the FCs there are 2 types of power steering: ESPS - Engine Speed Power Steering that is a power steering system based on speed engine. When RPMs go up a valve reduces the force of the hydraulic power steering. The other system used on FCs is the ECPS - Electronic Controlled Power Steering; there is a power steering computer that "reads" the veichle speed and opens some valves on the circuit that reduce the force of the power steering when the car speed grows.

ECPS system is more complex that ESPS and more expensive!

Mazda mounted ECPS system to S4 from S5 but only till 1988! Then Mazda mounted ESPS. That's why i asked you this info.

Turbonut

iTrader: (1)

Looks like the 1989 models have both:
GTU-Engine rpm sensing variable ps
GXL, Turbo, Convertible-Vehicle speed sensing variable ps
I would think the Turbo convertible would have the vehicle speed sensing, but been wrong before.

Venturer

Do you think that "Vehicle speed sensing variable ps" is so much better than Engine rpm sensing variable ps?

Did you drive both?

Venturer

Do you think that "Vehicle speed sensing variable ps" is so much better than Engine rpm sensing variable ps?

Did you drive both?

Turbonut

iTrader: (1)

Had a new '88 TII and then purchased a '89TII that we still have, and honestly, don't remember any difference between those two.

j9fd3s

iTrader: (3)

Mazda changed the steering rack ratio also, the Vehicle speed system is 15:1 vs the engine rpm system's 17:1. both systems feel largely the same, the FC has this crazy turn in response, and a stock car with the 15:1 feels like it can make a 90 degree turn, which is cool, but it can feel strange (the boxster felt like this too). the 17:1 rack feels more natural to me, it turns in more like a normal car.

the manual rack is 21:1 (or something like that), and it sucks, you need to move your hands really fast.

the Vehicle speed system has two pressure hoses on the pump, and the engine speed only 1. in the US the 1990-1991 cars can have either, system, with the more optioned cars tending to have the Vehicle speed system