930 Steering Ratio

[jrl]

I finally got around to reading the June 911 & PW article on the 930 engine. The gray sidebar on p. 103 mentions "the steering rack ratio was increased", presumably compared with the NA 911.

My 930 steers pretty heavily, more so than the couple of Carreras I test drove. I chalked it up to the wider track and tires, but quicker steering might explain this.

However, "increased" suggests a higher numerical ratio, i.e., slower, lighter steering. Is the 930's steering quicker, slower, or the same as the same vintage 911's? Mine's an '86.

[Emission]

Bump 'cause I want to know now...

[dean]

The 930 has slightly quicker steering. 3.1 turns lock to lock as apposted to 3.3 on the 911. My #'s are off but you get the idea.

[wcc]

FWIW my 930 'feels' quicker and lighter than my '85. Maybe it has something to do with Fuch's on the 930 and DP aftermarket wheels on the '85.

[kuehl]

hmmm, for some reason I recall the gear rack and pinion profiles are the same and the difference was in the two boss mounts in the casting.... guess we'll have to count those teeth and check the angle.

[Emission]

I just bought a new rack for my 930... I don't recall it being a "turbo-specific" part.

[kuehl]

Originally posted by Emission
I just bought a new rack for my 930... I don't recall it being a "turbo-specific" part.

As I recall the first 911's had a very nice gear set, extremely smooth, maybe pn 901-347-010-01, and then it went to the more commonly found 914-347-010-05 and then -06.

But the 930 used a pn 930-347-010-00. The only differnence that stood out in recollection was, between the "914-" vs. the "930-" prefix, was that the 914 used a M10x45 mm length bolt to secure it to the cross member, whereas the 930 used a short M10x35 mm length bolt.

But then again you won't know till you count those teeth and check the gear profile.

The feeling or confusion of a "quicker ratio" could relate to a limitation of full travel by something like a steering stop or even tire profile; my 73t 911 had rather narrow tires compared to the current 87 cab so the 87 in comparison steers like a "truck".

[jrl]

In my first e-mail, I mentioned wider tires could account for heavier steering. Last night mowing the grass--when things make most sense--I vaguely recalled that NA 911's use 205 fronts, like the turbo. That right? If so, it shoots my theory down.

[Jim2]

Some info I read a number of years ago stated the 930 is 2.5 turns lock to lock, and the 911 is 3.0 turns.

Jim

[kuehl]

Originally posted by Jim2
Some info I read a number of years ago stated the 930 is 2.5 turns lock to lock, and the 911 is 3.0 turns.

Jim

hmmm. ....
Well I guess the only way to know for sure is to take one of each (out of the car) and do a quickie roll test.