bump steer on the 993
Thread Starter
Three Wheelin'
Joined: Sep 2003
Posts: 1,507
Likes: 0
From: Dayton, OH
bump steer on the 993
In reading through the archived posts, it seems that one way of reducing bump steer (and possible adding a lttle more precision to the steering) is with the addition of the Evo uprights along with either the ERP or RS/GT2 tie rods.
a couple of questions: 1) if the bump steer is not bad and I am looking for simply some extra steering precision, is it adviseable to simply switch out the tie rods? If the answer is yes, is it adviseable to go with the RS/GT2 variety? I know they are not adjustable like the ERP, but does it matter if the uprights aren't added with it?
2) I looked for RS/GT2 tie rods in the PET, but didn't see any thing for 95-98 carrera... only the stock tie rods. Am I looking in th wrong place for them?
thanks
a couple of questions: 1) if the bump steer is not bad and I am looking for simply some extra steering precision, is it adviseable to simply switch out the tie rods? If the answer is yes, is it adviseable to go with the RS/GT2 variety? I know they are not adjustable like the ERP, but does it matter if the uprights aren't added with it?
2) I looked for RS/GT2 tie rods in the PET, but didn't see any thing for 95-98 carrera... only the stock tie rods. Am I looking in th wrong place for them?
thanks
Passed On
Rennlist Member
Rennlist Member
Joined: May 2001
Posts: 3,031
Likes: 3
From: Pittsburgh, PA
Drive down the highway and twitch the steering wheel back and forth rapidly about half an inch either direction. If you don't feel the front end move, might change the tires to a more aggressive pattern or check your tire pressures (my Bridgestone RE750s are comparatively "mild" but I can feel the car move when I twitch the wheel like this- even with 86K miels on original rods/suspension arms). If you DO feel it move, leave everything alone - car is fine. Remember, like me, "pothole" is a common and very well known word in this part of the country.
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Apr 2002
Posts: 5,456
Likes: 185
Alex
Unless you are at or below RS height at least and you track aggressively you should not need the bump steer kit. Steering precision does not really get impacted, Ray's suggestion is spot-on. It is rather to avoid the front from "bumping" and drifting when you hit a road/track imperfection.
The GT2 tie rods can be bought from Porsche Motorsports or a third party vendor such as Gert for instance, you will not find them on PET.
Unless you are at or below RS height at least and you track aggressively you should not need the bump steer kit. Steering precision does not really get impacted, Ray's suggestion is spot-on. It is rather to avoid the front from "bumping" and drifting when you hit a road/track imperfection.
The GT2 tie rods can be bought from Porsche Motorsports or a third party vendor such as Gert for instance, you will not find them on PET.
Thread Starter
Three Wheelin'
Joined: Sep 2003
Posts: 1,507
Likes: 0
From: Dayton, OH
thanks for the advice. Yes, I seem to have a bit of a disconnected feel through my steering wheel. My tires are Pilot Sports with correct pressure.
I guess its all relative. I have a friend with an m5. When he drives my car, he can't believe how responsive the steering is. I, on the other hand, am not satisfied unless every twitch of the wheel translates into front end response.
Would the gt2 tie rods by themselves help with the responsiveness?
I guess its all relative. I have a friend with an m5. When he drives my car, he can't believe how responsive the steering is. I, on the other hand, am not satisfied unless every twitch of the wheel translates into front end response.
Would the gt2 tie rods by themselves help with the responsiveness?
RL Community Team
Rennlist Member
Rennlist Member
Joined: Apr 2002
Posts: 3,985
Likes: 229
From: Seattle
As I recall, one of the more track-oriented cars like the 964rs had a manual steering box... I think that there was someone here who had converted their 993 over to that manual rack. Anyone recall? I may be incorrect as I am running on only a couple hours of sleep.... 
Thread Starter
Three Wheelin'
Joined: Sep 2003
Posts: 1,507
Likes: 0
From: Dayton, OH
I have consistently considered going to manual steering and my mechanic keeps trying to talk me out of it. He says I will hate it for the street. I would love to know if anyone has done it andlikes the result.
Kim - Evo uprights, rs tie rods and you still don't feel connected? wow! I'm glad you told me that. Its saved me a lot of expensive mods. Have you considered the GT2 tie rods that go specifically with the evo uprights?
Kim - Evo uprights, rs tie rods and you still don't feel connected? wow! I'm glad you told me that. Its saved me a lot of expensive mods. Have you considered the GT2 tie rods that go specifically with the evo uprights?
RL Technical Advisor
Joined: May 2001
Posts: 11,870
Likes: 75
From: Portland Oregon
Originally Posted by Jean
Alex
Unless you are at or below RS height at least and you track aggressively you should not need the bump steer kit. Steering precision does not really get impacted, Ray's suggestion is spot-on. It is rather to avoid the front from "bumping" and drifting when you hit a road/track imperfection.
The GT2 tie rods can be bought from Porsche Motorsports or a third party vendor such as Gert for instance, you will not find them on PET.
Unless you are at or below RS height at least and you track aggressively you should not need the bump steer kit. Steering precision does not really get impacted, Ray's suggestion is spot-on. It is rather to avoid the front from "bumping" and drifting when you hit a road/track imperfection.
The GT2 tie rods can be bought from Porsche Motorsports or a third party vendor such as Gert for instance, you will not find them on PET.
Just so you know, Rennsport Systems carries ALL of those race parts you mentioned here (and then some) as well as Porsche Motorsports since they do not stock much 993 stuff anymore.
Sorry, Sir,.......I couldn't resist,.....
Trending Topics
Advanced
Joined: Oct 2004
Posts: 69
Likes: 0
From: Wilmette, Illinois
After I installed the ERP monoballs in the front and rear of my car the steering became extremely precise. Any amount of steering input results in the car turning. It made my 97,000 mile car feel better than new! I don't think I'd switch to manual steering. My beater Sentra has manual steering with 195's on it and it's a royal pain. I even overfill the tires a little to try and make it a little easier. I couldn't imagine the effort it would take with 225 SportCups!
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
9 Vehicles Porsche Helped Engineer that Aren't Porsches
Verdad Gallardo
9 Features and Characteristics That Only Porsche People Understand
Verdad Gallardo
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way
Joe Kucinski
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)
Verdad Gallardo
Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner
Joe Kucinski
This Builder Is Turning Heads With Its Slantnose 911 Creation
Verdad Gallardo
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture
Verdad Gallardo
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Apr 2002
Posts: 5,456
Likes: 185
Dear Steve
If you run a search, you will see how often I recommend your shop Even more so in private! You have always been very helpful. I recommended Gert instinctively because I still have the pictures of his bump steer kit in my mind, but of course you both, and other sponsors are top notch people. 
Definitely easier to get the tie-rods from you guys than Porsche Motorsports.
Alex
The 993GT2 street and Evo versions came both with the power steering (some teams did remove them) so IMHO, the benefits far outweigh the downsides especially for a (mainly) street car.
If you run a search, you will see how often I recommend your shop
Even more so in private! You have always been very helpful. I recommended Gert instinctively because I still have the pictures of his bump steer kit in my mind, but of course you both, and other sponsors are top notch people. Definitely easier to get the tie-rods from you guys than Porsche Motorsports.
Alex
The 993GT2 street and Evo versions came both with the power steering (some teams did remove them) so IMHO, the benefits far outweigh the downsides especially for a (mainly) street car.
Technical Guru
Rennlist Member
Rennlist Member
Joined: May 2002
Posts: 8,138
Likes: 122
From: USVI
I've had manual steering in my 964RS-A for 11 years now and it rocks. Even for long 6-8 hour drives I love it and over the years I have come to hate the lack of feeling you get with power steering in other cars. It makes everything else feel like your driving a school bus. You have to remember that in comparison to cars like a Nissan Sentra the Porsche 993 has almost no weight over the front wheels.
RL Community Team
Rennlist Member
Rennlist Member
Joined: Apr 2002
Posts: 3,985
Likes: 229
From: Seattle
As I recall, one of the more track-oriented cars like the 964rs had a manual steering box... I think that there was someone here who had converted their 993 over to that manual rack. Anyone recall? I may be incorrect as I am running on only a couple hours of sleep....
RL Community Team
Rennlist Member
Rennlist Member
Joined: Apr 2002
Posts: 3,985
Likes: 229
From: Seattle
Jason, do you have the part number for your rack? I am thinking about converting over. I show a part #964 347 011 02 in PET, but I am thinking that there is another application and part numnber from another model... cheaper than an RSA rack.
Also, are the other tie-rods solid ended as opposed to rubber on the inside as is stock on the 993? The turbo tie rod conversion I did on my 87 Cab made a HUGE difference, and they were solid ended.
Thanks
Also, are the other tie-rods solid ended as opposed to rubber on the inside as is stock on the 993? The turbo tie rod conversion I did on my 87 Cab made a HUGE difference, and they were solid ended.
Thanks
Thread Starter
Three Wheelin'
Joined: Sep 2003
Posts: 1,507
Likes: 0
From: Dayton, OH
I am also interested in understanding the tie rod differences. From my research, the RS tie rods have a harder rubber than stock while the gt2/Evo tie rods are completely solid (they are also about twice the cost of the rs tie rods). Am I correct in my thinking?
Thread Starter
Three Wheelin'
Joined: Sep 2003
Posts: 1,507
Likes: 0
From: Dayton, OH
in addition, my understanding is that the turbo tie rods are used to cure bump stgeer on on pre-993 style 911's. Are the turbo tie rods therefore different than the RS tie rods (I would imagine these are the ones used on the 993RS, maybe the 964RSA??)