PDA

View Full Version : Power vs. manual steering for enduros



rsportvolvo
07-21-2010, 06:55 PM
Is there a big difference on driver fatigue running a power steering car vs. manual steering? Are the parasitic losses of the PS pump worth the benefit of driver comfort?

JLawton
07-21-2010, 07:07 PM
Power steering all the way!!!!!

JoshS
07-21-2010, 07:40 PM
I think it'll depend on the car, but I can tell you that when a practice wreck took out the power steering pump of my SSC Mazda3, I raced it without.

The steering feel was spectacular, but at the end of the race once the adrenaline subsided, I couldn't even lift my arms up to shake someone's hand. I was exhausted. Maybe if the car had a slower rack that was designed to be used manually, that would be different. I would never disable the PS on purpose after that experience. I'm not the biggest, strongest guy on the track though, so YMMV.

Greg Amy
07-21-2010, 08:05 PM
+1 to the above. I did a couple of 1.5-hour stints at NJMP in an SM that had a de-powered rack, and I really missed my power steering (both my NX and the Integra had/have it)...

Does Pablo have power steering...? I never had a problem with that car. But maybe that has more to do with whether the rack was designed for power or not...

Knestis
07-21-2010, 08:25 PM
...Does Pablo have power steering...? I never had a problem with that car. But maybe that has more to do with whether the rack was designed for power or not...

Yup. I think it's a good thing.

K

callard
07-22-2010, 09:45 AM
Both my enduro IT-B cars had manual steering - groan. The IT-S enduro car has power - smiles. The power steering smooths out some of the jerky feedback and you don't have to work as hard in steering the car. Power steering is a great aid in an endurance race. My sprint car doesn't have power and I wish it did.

rsportvolvo
07-22-2010, 11:22 AM
As for car specific I would say that aside from the physical layout caster settings have the most influence on steering weight. Seeing that my Volvo 240 has MacPherson struts I will be running quite a bit of caster.

Thanks for the feeback. I figure I can tune the amount of assist with pulley sizes. This way I get some feel back without going full manual. Power assist it is.

callard
07-22-2010, 12:08 PM
Too much caster and your arms will look like Popeye after 45 minutes.
BTDT
Chuck

timo944
07-23-2010, 11:56 AM
What about PS pump reliability? In the 944 many of us use manual steering due to reliability issues of the pump and the belt flying off.

I have heard in the past that tech inspectors have required that if the steering is converted to manual, the entire system must be replaced, ie. the steering reck must be a bonefide manual rack and the pump and plumbing removed. This is what I did in the 944 and it's fine in a Enduro.

Greg Amy
07-23-2010, 12:02 PM
I have heard in the past that tech inspectors have required that if the steering is converted to manual, the entire system must be replaced, ie. the steering reck must be a bonefide manual rack and the pump and plumbing removed. This is what I did in the 944 and it's fine in a Enduro.
That's correct for an Improved Touring car, and only if the car you're racing came without power steering (e.g., you cannot convert an ITS Acura GS-R to a manual rack, because the power steering was standard equipment on that car).

GA

pfcs
07-23-2010, 04:11 PM
Having to use hand controls, pwr strg was de rigeur in my A2.
I underdrove it about 60% and could drive quite well one-handed.
I also cheated and installed a larger A3 reservoir; At normal "gearing" and very small reservoir. it would push fluid out. I don't really know which mod (or both) cured the problem. I figgered the large reservoir could be put under the allowance for hand-control modifications if someone really cared to make it an issue.

Matt93SE
07-25-2010, 10:52 PM
I de-powered the rack in my 240SX after it blew up first session at a DE, and with a 13" smaller-than-stock steering wheel, it was pretty rough. (Stock is about 14" dia.) Shortly after that, I bought a 15" wheel from Longacre and the steering is MUCHO better.

I now have the feel of a manual rack and I have the drivability of power steering.

I've spent 4+ hours a day on track in and my shoulders were sore at the end but not falling off or anything. (My neck was more sore than anything).

Overall steering effort is only slightly higher than stock, but I can still drive tight tracks with one hand on the wheel and do 3-pt turns in the driveway without too much trouble.