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914World.com _ 914World Garage _ Question on steering racks
Posted by: naro914 Nov 21 2011, 07:08 AM
Hi all,
My questions centers around the turning ratio's of the racks. Are there different ones or are all 914 racks the same? I remember a while ago - maybe years - someone posting a 914/6 GT rack saying the turning ratio was different than stock. Then I think I saw someone say they had a different ratio rack, but I can't find those posts, or confirm any information on them.
So...are there any steering racks with better ratio's than stock? i.e. turn the steering wheel less to get more turn of the wheels?
thanks all
Posted by: scotty b Nov 21 2011, 07:20 AM
I'm pretty sure a 911 rack has a quicker ratio, but I can't 100% promise that.
I do know the part numbers are different for whatever that is worth 
Posted by: naro914 Nov 21 2011, 07:35 AM
does it fit?
Posted by: SLITS Nov 21 2011, 08:04 AM
Yes it fits ... as far as I remember, the difference is in the input shaft length. If there is a difference in turn ratio I've never paid attention.
I'll see if I can find out today.
Posted by: McMark Nov 21 2011, 11:07 AM
HA! I was just researching this last night. What I ended up finding in my 911/912 Clymer manual was:
The 65-66 SWB 911, and all 912 steering racks are 16.5:1.
All others, including 914, are 17.78:1.
This is a reduction of 3.1 turns to lock, down to 2.9 turns. Not a huge amount, if you want more Quaife sells a http://www.quaife.co.uk/shop/products/qsf3q001-1, but that takes more work to install.
I haven't done the swap (yet), but as far as I can tell, you'll only need to swap the input shaft from the 914 unit, and then install turbo tie rods.
There was a bit of chatter on the 912 BBS about turbo tie rods being too short for the early rack, and Elephant sells a http://elephantracing.com/suspension/tierod/911turbotierod.htm. But again, I haven't seen this issue for myself.
I have a 66 912 here in the shop that I plan on pulling the steering rack to take some measurements and comparisons.
Sure would have liked the tighter ratio at last weekends autocross. Lots of steering wheel twirling on that course.
Posted by: r_towle Nov 21 2011, 11:11 AM
I looked into this years ago...when I was rebuilding my rack (s)
I seem to recall a 911 RS version that was a porsche part number with a much shorter ratio.
Its rare...but it also means the pinion gear exists.
Look up that part number on the stock rack and see if one our our Porsche parts guys can dig a bit deeper to look for the other pinion gear.
Its a little stub that is about 3 inches long...not super hard to make, but easier to buy if its on some shelf somewhere..
I looked into getting one,,,,not worth the effort for me at that time.
All the 911 racks seem to be the same physical size...at least all the 911 racks from cars that have the same front suspension as our 914 does.
Rich
Posted by: SLITS Nov 21 2011, 11:19 AM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Posted by: McMark Nov 21 2011, 11:28 AM
Rich, here is a http://www.pbase.com/slidevalve911rsr/myrsr_suspension_rack_and_pinion_quick_ratio.
Posted by: McMark Nov 21 2011, 11:31 AM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
Posted by: scotty b Nov 21 2011, 12:53 PM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
AWWWW YEAH !!
Attached image(s)
Posted by: MDG Nov 21 2011, 01:02 PM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
AWWWW YEAH !!
I love the brocade on Slits' jacket. Very nice.
Posted by: Eric_Shea Nov 21 2011, 01:04 PM
But is it... positively 3.1 turns?
Posted by: McMark Nov 21 2011, 01:05 PM
That I don't know....
Posted by: scotty b Nov 21 2011, 01:14 PM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
AWWWW YEAH !!
I love the brocade on Slits' jacket. Very nice.
Eric is just off to the side acting as the formal judge, and remover of bodies afterwards. He's in dashing red and gold outfit with his hair piled high and properly powderd
Posted by: SLITS Nov 21 2011, 01:45 PM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
Don't care Mark .... you can argue with A1/Cardone, ATSCO and the other rack rebuilders. Those are the specs they operate by.
Posted by: naro914 Nov 21 2011, 02:47 PM
now children, I didn't mean to start a fight here.
Honestly I don't care what the stock ratio is, I want one that is better than stock ratio.
I noticed that Patrick Motorsports sells a Quaife 2.5 lock to lock system.
Posted by: SLITS Nov 21 2011, 05:55 PM
As a core supplier, The 911 and 914 manual rack are the same with a different part number. Turn ratio is 2.750 turns lock to lock.
We think that the 911 Turbo could be different, but never have been able to get a sample.
Sorry Slits. 914 rack is absolutely 3.1 turns lock to lock.
AWWWW YEAH !!
I love the brocade on Slits' jacket. Very nice.
Eric is just off to the side acting as the formal judge, and remover of bodies afterwards. He's in dashing
Fixed it for ya!
No fight ... we are due for one, but the "A______s" won't allow it.
Posted by: McMark Nov 21 2011, 06:21 PM
Awwww, come on! 
Posted by: r_towle Nov 21 2011, 06:43 PM
http://www.youtube.com/watch?v=kQFKtI6gn9Y
Posted by: naro914 Nov 21 2011, 08:57 PM
http://www.youtube.com/watch?v=kQFKtI6gn9Y
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