944 track car, manual rack or plugged power rack?
#16
All the front running 944 guys around here run the looped PS rack. The manual rack is easier to turn because it has a higher ratio but that makes it slower (have to turn the wheel more to get the same amount of change). I ran a looped PS rack on the racecar last year with 275's up front and it was fine.
#17
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Here is photo of me at Tremblant entering turn 14 (Namerow), the slowest turn of the track, my hands located at 9 and 3. You can see the difference between the actual wheel position and steering wheel (Plugged version of the ps). It's a little bit less with the manual rack and definitely less hard to turn.
c.
#18
Drifting
Not when you remove the power in the power steering assembly. Trust me. I really know what I'm talking about. And you need Rambo's arms to turn at hairpins.
Here is photo of me at Tremblant entering turn 14 (Namerow), the slowest turn of the track, my hands located at 9 and 3. You can see the difference between the actual wheel position and steering wheel (Plugged version of the ps). It's a little bit less with the manual rack and definitely less hard to turn.
c.
Here is photo of me at Tremblant entering turn 14 (Namerow), the slowest turn of the track, my hands located at 9 and 3. You can see the difference between the actual wheel position and steering wheel (Plugged version of the ps). It's a little bit less with the manual rack and definitely less hard to turn.
c.
#19
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Sorry - that is incorrect. A rack and pinion steering rack uses a fixed gear size and toothed rack which fixes the gear ratio. The power steering portion of the rack uses hydraulic pressure to assist in moving the rack so that is is easier to turn - it doesn't change the ratio. So yes the PS rack with the pump removed is more difficult to turn but the ratio is unchanged and has a lower ratio than the manual steering. That said I have driven on plenty of tight tracks with a widebody 944 Turbo running 275's out front and 315's in the rear and while is takes a little more effort it certainly doesn't take Rambo arms. I do have a little toe out on the front alignment which helps - not sure what my caster is set at off the top of my head but it is at the max eccentric position.
At Tremblant the effort was high but sustainable. At Icar, it was just horrible.
It is just my opinion though! But I'm not recommending doing that.
c.
#20
Nordschleife Master
I often wondered about this so I checked in the Manual Vol-3, Chap-48.
The manual rack has 3.84 to 4.02 turns lock to lock at a ratio of 22.39:1
The power rack has 3.24 turns lock to lock at a ratio of 18.85:1
Turning circles are identical on both manual and power.
So the manual rack requires more turns but its a higher ratio.
The power rack requires less turns but at a lower ratio.
This would suggest that you should have slightly better control and feedback with the manual rack and that is what I have found in my car. Plugging the power rack would not give you the advantages of a full manual rack set-up as you are still working with power rack ratios and steering wheel travel, which are already inferior to the manual rack. I can see however that the quicker power rack lock to lock would be an advantage on an autocross or tight track, but without the power assistance you would have to go to the gym. On the other hand the manual racks higher ratio would be a bit more sensitive for regular street driving, causing you constantly adjust you straight line steering more than the power rack.
The manual rack has 3.84 to 4.02 turns lock to lock at a ratio of 22.39:1
The power rack has 3.24 turns lock to lock at a ratio of 18.85:1
Turning circles are identical on both manual and power.
So the manual rack requires more turns but its a higher ratio.
The power rack requires less turns but at a lower ratio.
This would suggest that you should have slightly better control and feedback with the manual rack and that is what I have found in my car. Plugging the power rack would not give you the advantages of a full manual rack set-up as you are still working with power rack ratios and steering wheel travel, which are already inferior to the manual rack. I can see however that the quicker power rack lock to lock would be an advantage on an autocross or tight track, but without the power assistance you would have to go to the gym. On the other hand the manual racks higher ratio would be a bit more sensitive for regular street driving, causing you constantly adjust you straight line steering more than the power rack.
#21
Drifting
Not sure where you guys are getting the going to the gym stuff about the plugged PS rack. Your not gonna get much more effort than 275 Hoosiers up front and while it takes more effort than PS it is by no means difficult, other than the real slow speed stuff in the paddock. Also keep in mind we are talking about track cars here and one relevant piece of information is what are the front runners doing. Here is the NASA Great Lakes region for instance, the top 5 cars (at least) are all running plugged PS racks and many of them have switched from the manual racks - just too slow of a turning ratio.
#22
I'm with Skip folks. I really don't think you guys are removing the hose from the pump. Only that will make it difficult to steer. Seriously look at my autocross video. I'm easily correcting with one hand. And quickly at that. I guess its all opinion on ratios but, I'm pretty sure a tighter rack will give you a quicker feedback, and a good feel. I Checked today and Many of the race cars at Pro-Technik have looped power steering racks. FWIW.
#24
Herr Unmöglich
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We ran our 83 ChumpCar with manual steering and no one complained. I did 2 different 2 hour stints and it did not bother me at all. I run manual in my 944 Cup car too... lighter and simpler.
#25
C'mon guys... you gotta love the post
"Not when you remove the power in the power steering assembly. Trust me. I really know what I'm talking about. And you need Rambo's arms to turn at hairpins.
Here is photo of me at Tremblant entering turn 14 (Namerow), the slowest turn of the track, my hands located at 9 and 3. You can see the difference between the actual wheel position and steering wheel (Plugged version of the ps). It's a little bit less with the manual rack and definitely less hard to turn."
I think the phrases to key in on here is " know what I am talking about and plugged version of PS" Anyone who has tried both the plugged and looped versions knows that the looped is much easier to turn. Sorry.... don't mean to be crucial but plugged racks are notoriously hard to steer
"Not when you remove the power in the power steering assembly. Trust me. I really know what I'm talking about. And you need Rambo's arms to turn at hairpins.
Here is photo of me at Tremblant entering turn 14 (Namerow), the slowest turn of the track, my hands located at 9 and 3. You can see the difference between the actual wheel position and steering wheel (Plugged version of the ps). It's a little bit less with the manual rack and definitely less hard to turn."
I think the phrases to key in on here is " know what I am talking about and plugged version of PS" Anyone who has tried both the plugged and looped versions knows that the looped is much easier to turn. Sorry.... don't mean to be crucial but plugged racks are notoriously hard to steer
#27
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I'm still trying to figure out why Charles seems to be turning right on a left hand turn....unless my eyes are deceiving me???
#28
Burning Brakes
one thing which you may want to consider is the tire, and i mean the actual tire, not just the size. i switched my 951's power steering out a few years ago and then spent the next 2 years kicking myself. the car was very difficult to drive and every single time i made a right turn as when turning off a main road into a side street, i would have to slow down to such a ridiculously low speed, otherwise i was not strong enough to turn the steering wheel quickly enough. all this time i was running some crappy sumitomo tires (205/50-17) which came on a set of 17" cup wheels i had bought, so when i finally upgraded to some michelin pilot sports in 225/45-17 i expected the effort to get worse but these tires transformed the car. gone was the insanely difficult parking effort, gone was the previously mentioned slow speed turn in on every tight turn, gone was the bump steer and wheel fighting back in my hands. and no change to the alignment was made at the time. the only change was to the michelins. i still don't know why exactly but these tires transformed the manual steering. and now after having the pilot sports on for about 2 years, the only time i ever even think that the steering requires a high effort is when parallel parking and even then it's not so bad. and furthermore, i've had many manual steering cars and the 951 is the lightest steering of any the manual VW's i ever owned or any other manual steering car i've driven.
i still question whether it would be the perfect choice for the track. the few times i tracked my car was with the power rack and at the end of one of the days i ended up with blisters on my hands (no gloves though) so the track is obviously very hard on the body.
also, can someone explain the looped rack or point to a link on how to do this? i'm putting my alfa milano back together and would like to go this route as the milano racks are just as bad as the 944's when it comes to leaking (and a whole lot more difficult to remove from the car.)
thanks.
i still question whether it would be the perfect choice for the track. the few times i tracked my car was with the power rack and at the end of one of the days i ended up with blisters on my hands (no gloves though) so the track is obviously very hard on the body.
also, can someone explain the looped rack or point to a link on how to do this? i'm putting my alfa milano back together and would like to go this route as the milano racks are just as bad as the 944's when it comes to leaking (and a whole lot more difficult to remove from the car.)
thanks.
#29
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Guys,
I tried the 3 solutions (PS, then plugged PS, then manual, in that particular order). Track car only. All with R-Compound 245 or 255 at the front.
If were to do it again, I would either leave the PS or go directly to the manual.
I really disliked the ps without the power in. It was not fun to drive the car with it. And in my case, on short tracks, after 2 complete hot days at the track, my arms were dead.
Patrick, I'm turning right!
c.
I tried the 3 solutions (PS, then plugged PS, then manual, in that particular order). Track car only. All with R-Compound 245 or 255 at the front.
If were to do it again, I would either leave the PS or go directly to the manual.
I really disliked the ps without the power in. It was not fun to drive the car with it. And in my case, on short tracks, after 2 complete hot days at the track, my arms were dead.
Patrick, I'm turning right!
c.
#30
Nordschleife Master
I used Castrol wheel bearing grease and it was too light, made the steering too "twitchy". Went for a heavier grease, can't remember the brand but got the heaviest they had at Autozone and it feels just right.