How big are your muscles ??? Power Steering question

[f1racr]

So we are in the final stages of getting our track car to turn a wheel in anger, but one thing I've wondered about is power steering as we intend to do some endurance events and although my car is now a manual, it started life as an auto so has the power assisted rack, but of course it's usually tied into the auto trans ecu and steering column sensors etc so I'd just assumed from the start that we would disable the system and run it as a manual rack.

Once we'd made up the woodward steering column I was surprised how light the steering was relative to what I'd expected, so I assume when the car is underway it's not going to be too bad, but with basically slicks on the car I wondered if it's worth us investing some time trying to get the power rack working to try and make life easier, or if someone here could offer some real world experience to save us some time if they think it's not valuable.

I hope that all makes sense........ as always, any advice is very much appreciated.

 

[TyraNSX]

The stock system is designed to cut out assist above 20 or 25mph so you would need to override that to be on all the time. Personally, the only time I notice the lack of assist is from a stop or very low speeds (parking, creeping around gas pumps, etc.) so once the car is rolling slightly it gets very easy and has excellent feel from the manual rack. Since you're going endurance racing I can see where fatigue would be a concern so maybe the Realtime guys or the JGTC guys already worked out a solution for this?

http://www.nsxprime.com/wiki/Electric_Power_Steering

 

[f1racr]

Thanks for the reply. There's plenty of aftermarket solutions out there... Woodward make one that Dale is using on his LS7 NSX build so I could go down that track, but it's a reasonable amount of work and cost if people who have raced here suggest it's not really worth the hassles.

I suspect it isn't worth the hassle, but I guess I didn't want to just rule it out without looking into it, as at this stage I'm still in the build mentality and I won't really want to get back into this frame of mind once I'm running the car if that makes sense.

 

[R13]

I know in-general a disabled power rack is usually heavier to steer than a dedicated manual rack, but my only point of reference with the NSX is a proper manual rack. From an endurance racing standpoint, I guess you'd have to weigh the benefit if, as TyraNSX states, there is no assist over 20mph vs. the "something else to go wrong" factor in a race that lasts multiple hours.

 

[f1racr]

Yeah, fair call I guess, that is another thing I guess would be interesting to know is if there is any drag with the EPS off. My understanding is that there is none as it's esstially just you turning the shaft on your own and the 2 parts of the motor don't physically touch each other so there should be no physical drag, maybe just some magnetic drag, but I never looked at the rack when we had it out earlier in the build to make a good assessment.

So if anyone knows the official answer to the above then that would be good to know too. I can only assume that with no assist above 20 or 25mph or whatever it is that if it was harder to steer than a true manual then it would have been complained about...

 

[docjohn]

I'm not sure you can compare a street driven nsx with skinny front tires to a race car with big front slicks and lots of camber and perhaps toe out....just sayin.

 

[f1racr]

Yep absolutely which is why I put it in this section...... I know there might not be many out there with helpful info on this exact subject, but if there is anyone then hopefully they will be here as there really isn't many other collections of NSX owners with race experience for me to ask !!

Just to add to the conversation, I am running Hoosier R6's in 245/35/18 and 295/30/18

 

[angus]

That car looks fantastic.

 

[f1racr]

Thanks We've worked our arses off on it for the last 18 months.

 

[Track Addict]

Just to add to the conversation, I am running Hoosier R6's in 245/35/18 and 295/30/18

I drooled at the tire sizes you chose. Really putting that widebody to use!

Car looks awesome and I am glad it is going to hit the tarmac very soon.