Civic Si First Impressions

[Nexus Flux]

I believe its a new trend in most new cars to not have a power steering pump running hydraulic fluid, but to be electrically operated

From the Honda Site

Power-Assisted Rack-and-Pinion Steering - Electric

I think this might need a little clarification.
As far as the RSX goes it's "An electronically controlled speed-sensing power-assist, rack-and-pinion system." There is a power steering pump but as the speed of the car increases the amount of power steering assistance goes down. The power steering fluid bypasses the rack and flows more freely thereby reducing the amount of HP loss from the power steering pump. My '90 Integra had a similar setup but the power steering fluid was routed through the tranny. It was a mechanically variable power steering.

Let me do some checking on the Civic setup as the Honda site is a little short on info. They do share many other components so I don't see why it would be much differnt between the EP3 and DC5 chassis.

[srivendel]

Here's something from the Car Connection:

Strict adherence to the latest SAE testing standards have the new Civic Si's engine rated at 197 horsepower instead of 200 but that doesn't mean there are no differences between it and the similar powerplant in the RSX Type-S. Code-named K20Z3, the Civic SI's all-aluminum engine is a member of Honda's K-Series family and shares, bore, stroke, displacement, DOHC cylinder-head design, four-valve combustion chambers, 11.0:1 compression ratio and a thrilling 8000 rpm redline with the 201-horsepower K20Z1 used in the 2006 RSX Type-S. However it has a balance shaft that produces smoother operation but increases parasitic drag. In compensation for that the K20Z3 uses electric power steering and also incorporates an electric throttle and its own unique aluminum intake manifold.

Interesting...

S.

[altiain]

I think this might need a little clarification.
As far as the RSX goes it's "An electronically controlled speed-sensing power-assist, rack-and-pinion system." There is a power steering pump but as the speed of the car increases the amount of power steering assistance goes down. The power steering fluid bypasses the rack and flows more freely thereby reducing the amount of HP loss from the power steering pump. My '90 Integra had a similar setup but the power steering fluid was routed through the tranny. It was a mechanically variable power steering.

Let me do some checking on the Civic setup as the Honda site is a little short on info. They do share many other components so I don't see why it would be much differnt between the EP3 and DC5 chassis.

No, the '06 Si (like the S2000, and several Mazdas like the 3 and RX-8 ) does not have a hydraulic power steering system at all. All power steering assist is through electronically actuated servos instead of hydraulic pumps.

This is one of the reasons the original S2000 was often maligned for a lack of steering feel and feedback. Since the servo assist is controlled by software instead of the traditional hardware feedback loop of a hydraulic power steering system, the “feedback” that you feel through the steering system is almost entirely artificial. The art is in getting the feedback generated by the software to mimic what you would get with a well-weighted traditional hydraulic power steering system… something that Honda’s engineers didn’t get very right on the original ’00 S2000.

However, they’ve made huge strides in feedback algorithms since then. I haven’t driven a new Si, but later model S2000s (‘04+) have dramatically better steering feel and “feedback” than the early cars. Still not as good as the best hydraulic systems, but the tradeoff is in reduced complexity, cost, and parasitic engine load.

[Adam Payrot]

Yeah that, Iain's got it right.

[Treibenschnell]

Iain's got it right.

Was there ever really any question whether Altiain was wrong?

[Nexus Flux]

Learn something new everyday.

In my defence, I said what I know pertains to the RSX and I was going to do some more checking into the EP3s. Also while I was writing my post 3 or 4 other people replied with some more info so that when I posted I was a few posts after the post I was replying to.

[Adam Payrot]

I think somebody on CRSX is currently trying to swap his RSX power steering for the Si's electric unit. I haven't read the thread in quite some time, so I don't know if he was successful.



<-------- classic. ::BigBird:

[Nexus Flux]

After reading Iain's post I started thinking about that. As long as the power steering system is on a seperate ECU it very well might be possible without too much trouble.

[Adam Payrot]

And HERE'S the guy...