993 vs 964

[ReOwner]

Hi all,
I am curious about the handling differences between the 964 (particularly the RSA) and the 993. I know the 993 has a suspension enhanced with the "Weisach" aspects from the 928, and the 993 has power steering while the RSA version of the 964 doesn't, but how do these translate into handling feel differences? (Assuming sport/modified susp on the 993.)

I'm interested in both track and street use; a relatively harsh street ride isn't a problem. But I am concerned about the power steering; my euro '81 SC didn't have power steering, and I really loved the handling of that car -- never felt a need for the PS. Also, does the rumored "tamer" handling take anything away from the rumored precision feel of the 964 RSA handling?

Not meaning to be inflamatory; it is very difficult to really try these cars in depth before buying, so I'm interested in all impressions.....

Thanks!
-frank

[Cobalt]

Originally Posted by ReOwner

Hi all,
I am curious about the handling differences between the 964 (particularly the RSA) and the 993. I know the 993 has a suspension enhanced with the "Weisach" aspects from the 928, and the 993 has power steering while the RSA version of the 964 doesn't, but how do these translate into handling feel differences? (Assuming sport/modified susp on the 993.)

I'm interested in both track and street use; a relatively harsh street ride isn't a problem. But I am concerned about the power steering; my euro '81 SC didn't have power steering, and I really loved the handling of that car -- never felt a need for the PS. Also, does the rumored "tamer" handling take anything away from the rumored precision feel of the 964 RSA handling?

Not meaning to be inflamatory; it is very difficult to really try these cars in depth before buying, so I'm interested in all impressions.....

Thanks!
-frank

To be honest i went from 2 SC's to a 964 turbo and 964 C2 which I currently own. I used to track one of the SC's and i currently track the C2. I only noticed a difference at low speeds when I had to fight the wheel. Once at speed I think you would barely notice it. The power steering does eliminate a lot of the bump steer that you get from the manual racks but now that I am used to it I prefer it to the non power steering rack.

The 993 feels slightly more planted over adverse road conditions. Typically conditions you would not find on a track. I like the 993 although I have a problem with the gearing of the 6 speed and prefer the 5 speed box myself. Although I hear the gearing on the ROW 993's is much better. Although the 993 is nice I think you will find it differs more by looks than anything else. For the extra $10k or so you will spend on a 993 you can do a lot of upgrades to a 964. I f you get a 993 get a varioram engine car. It has better power and less issues than the 95's.

Pros and cons to everything. The newer cars have more power better engine management but weigh more. The dual mass flywheel is the biggest let down IMO of either the 964 or the 993 and IMO is one thing to switch out immediately. Although the coil over suspension of the later cars is superior to the Tbars I think they are dated also and would upgrade them too. lowered center of gravity and stiffer springs makes a world of difference. Stay away from the multi adjustable systems unless you really think you need them. More trouble to dial in the way you want and once you have it right you won't wan to mess with them anyhow.

[Bill Verburg]

I am curious about the handling differences between the 964 (particularly the RSA) and the 993. I know the 993 has a suspension enhanced with the "Weissach" aspects from the 928, and the 993 has power steering while the RSA version of the 964 doesn't, but how do these translate into handling feel differences? (Assuming sport/modified susp on the 993.)

The 993 received several enhancements to the suspension design, both front and rear, that contribute to "sportier" handling characteristics relative to 964.

Among these in front are
quicker steering
25mm wider track
10mm larger scrub radius
more caster
more negative camber
less toe

both 964 and 993 have a suspension designed to reduce the impact of road irregularities, making them more stable on rough roads than 911. Rough roads are a fact of life(even track life)

All of these attributes can be further enhanced w/ aftermarket suspension.

In the back the 964 received a version of the "Weissach" axle that induces some negative toe during braking and cornering. For sportier handling the elastic bushings that are the heart of this effect are replaced w/ less elastic or solid bushings.

The 993 recieved a further enhancement w/ the same sort of characteristics. Again for sportier handling less elastic or solid bushes are prefered. There are more bushes on a 993 which is the big reason that they are more expensive to set up for ttrack use.

either 964 or 993 is a wonderful track platform but the only 2 categories where a 964 comes out ahead is in cost and the #s produced.

[Bill Verburg]

Originally Posted by Cobalt

To be honest i went from 2 SC's to a 964 turbo and 964 C2 which I currently own. I used to track one of the SC's and i currently track the C2. I only noticed a difference at low speeds when I had to fight the wheel. Once at speed I think you would barely notice it. The power steering does eliminate a lot of the bump steer that you get from the manual racks but now that I am used to it I prefer it to the non power steering rack.

The 964/993 suspension is designed to be relatively immune to road irregularities, much more so than 911 this has nothing to do w/ p/s or bump steer. This compliance should not be confused w/ bump steer, caused by vertical misalignment of the steering arm and hub when a car is lowered, none of these are immune to bump steer. On a rough track the 993 will be far more compsed than a 911. I like the 993 p/s, not because of effort , but rather because of steering ratios, fastest to slowest 993, 911, 964

Originally Posted by Cobalt

The 993 feels slightly more planted over adverse road conditions. Typically conditions you would not find on a track. I like the 993 although I have a problem with the gearing of the 6 speed and prefer the 5 speed box myself. Although I hear the gearing on the ROW 993's is much better. Although the 993 is nice I think you will find it differs more by looks than anything else. For the extra $10k or so you will spend on a 993 you can do a lot of upgrades to a 964. I f you get a 993 get a varioram engine car. It has better power and less issues than the 95's.

I agree that either a 964 or 993 will feel more planted than a 911, the 993 more so(see above)
I also agree that US 993 gearing sucks
but US 964 and 993 both have virtually the same gearing 1-3, which will take you to just under 100mph. From there 964 has 2 more that go to ~150, 993 3 more that go to a theoretical 180 or so.

US 993 really comes alive when regeared to ~ 160top

Originally Posted by Cobalt

Pros and cons to everything. The newer cars have more power better engine management but weigh more. The dual mass flywheel is the biggest let down IMO of either the 964 or the 993 and IMO is one thing to switch out immediately. Although the coil over suspension of the later cars is superior to the Tbars I think they are dated also and would upgrade them too. lowered center of gravity and stiffer springs makes a world of difference. Stay away from the multi adjustable systems unless you really think you need them. More trouble to dial in the way you want and once you have it right you won't wan to mess with them anyhow.

numerical comparison 964 993, US,manual trans, 2wd coupes factory #s
weight(kg) normal1350 1370
weight(kg) RS 1200 1270

hp normal 250@6100 272@6100(285@6300vram)
hp RS 260@6100 300@6500

brakes normal rotor f/r 298x28/299x24 304x32/299x24
brakes RS rotor f/r 322x32/299x24 322x32/322x28

brakes normal axle pad area cm^2 f/r 170/170 250/170
brakes RS rotor f/r 250/170 302/250

wheels & tires normal 205/55 & 225/50 x16 on 6 & 8 205/55 & 245/45 x16 on 7 & 8

wheels & tires optional 205/50 & 255/40 x17 on 7 & 8 205/50 & 255/40 x17 on 7 & 9

wheels & tires normal 205/55 & 225/50 x16 on 6 & 8 205/55 & 245/45 x16 on 7 & 8

wheels & tires RS 205/50 & 255/40 x17 on 7.5 & 9 225/40 & 265/40 x18 on 8 & 10

Any model can be made to be more track ready w/ suspension, wheel/tire & brake upgrades. It's just generally easier to do on a 993 if not cheaper

[Cobalt]

Originally Posted by Bill Verburg

The 964/993 suspension is designed to be relatively immune to road irregularities, much more so than 911 this has nothing to do w/ p/s or bump steer. This compliance should not be confused w/ bump steer, caused by vertical misalignment of the steering arm and hub when a car is lowered, none of these are immune to bump steer. On a rough track the 993 will be far more compsed than a 911. I like the 993 p/s, not because of effort , but rather because of steering ratios, fastest to slowest 993, 911, 964

I agree I should not have used the term bump steer. Unfortunately, I am at a loss for words. I guess I was trying to say input? The manual rack will move constantly over every imperfection vs the p/s rack which vibrates a bit less. I am still not sure if I am explaining myself properly. Although the manual rack gives more input I find it to be excessive or unnecessary most of the time.

I never really took into consideration the steering ratios. I prefer the feel of the 964 myself. Is this why I consider the 993's to feel nervous at speed. I found my C2 and turbo to be much more stable and controllable at high speeds than the 993's I have driven. Although I find the 993's to be easier to autocross I prefer the feel of the 964 on the track. (that is after it has had a simple suspension, brake and tire/wheel upgrade)

[Bill Verburg]

Originally Posted by Cobalt

I agree I should not have used the term bump steer. Unfortunately, I am at a loss for words. I guess I was trying to say input? The manual rack will move constantly over every imperfection vs the p/s rack which vibrates a bit less. I am still not sure if I am explaining myself properly. Although the manual rack gives more input I find it to be excessive or unnecessary most of the time.

I never really took into consideration the steering ratios. I prefer the feel of the 964 myself. Is this why I consider the 993's to feel nervous at speed. I found my C2 and turbo to be much more stable and controllable at high speeds than the 993's I have driven. Although I find the 993's to be easier to autocross I prefer the feel of the 964 on the track. (that is after it has had a simple suspension, brake and tire/wheel upgrade)

The 911 steering wheel feels alive becase of a lack of compliance to road irregularity in the fore & aft direction and the relatively large scrub radius used on 911 front ssupensions. I can understand why afficianados of the 911 like it it is sort of sensous.


Most 964 drivers are put off by the 993 ratios, I don't understand why. I suppose it is just different form what they are used to.

[Cobalt]

Originally Posted by Bill Verburg

Most 964 drivers are put off by the 993 ratios, I don't understand why. I suppose it is just different form what they are used to.

More than likely. I am sure if I drove a 993 for a while I would adapt subconsciously. I find I am never happy with any 911 until I have tweaked it to my personal tastes anyhow.

[aigel]

I like the 993 steering. It is very fast and quite firm, especially at speed and with a well set up suspension. You should drive a well set up 993. Do not confuse p/s on a 911 with that in your grandmas Oldsmobile.

George

[ReOwner]

Wow, this is all fantastically helpful; thanks!

I had actually always wanted faster steering in the SC; I had talked endlessly with a guy who builds racks for Formula Atlantic, etc, cars about making a new custom rack, but never pulled the trigger. (I was more than a little concerned that without P/S, a faster ratio would have been just too much in parking lots, etc - the SC was still a street car, too.)

I did lift the rack in the SC with small spacers to improve the bump steer; didn't cure it (correct me if I'm wrong, but with a McPhearshon suspension, I don't think it is possible to eliminate bump steer). I did this partially to try to improve the highway characteristics; at the time I was doing a lot of highway driving, and found the SC to be a very lively and active car, which was quite exhausting for a 300 mile drive. (Exhausting in a good way generally, and far better than being lulled to sleep like a current so-called sports car I own is.) I had previously attributed the liveliness to bump steer (figuring that the steering was always being disturbed from small side-side variations in the road), but it probably had more to do with overall suspension stiffness, etc.

Anyway, thanks to all for some excellent info -- I'm looking forward to a new acquisition!

-frank

[ReOwner]

One more question: how do these all compare in terms of feedback at the limit, when they are about to break loose? I imagine that the 993 and 964 have both improved relative to the SC, with more feedback/warning? Or has the more docile street behavior led to more violent transitions at the limits on the track?

Thanks again, and happy Thanksgiving all!
-frank

[aigel]

Originally Posted by ReOwner

One more question: how do these all compare in terms of feedback at the limit, when they are about to break loose? I imagine that the 993 and 964 have both improved relative to the SC, with more feedback/warning? Or has the more docile street behavior led to more violent transitions at the limits on the track?

Thanks again, and happy Thanksgiving all!
-frank

The difference in grip at the limit, especially in the rear is astounding. I guess 10" wide wheels in the rear help but it's also the 3 link suspension on the 993 that really does some magic. I have recovered from situations on the track in the 993 that would have sent me into the weeds at 90mph in the SC, no question.

George

[ninesixfour]

Speaking purely of the track experience, having gone from a 964 to a Euro SC I have to say the ultimate would be a combination of the 2 (to me this would be a 964 Euro Cup). I love the feedback of the manual steering rack and when I install turbo tie rods I expect it will feel even better. The suspension on the 964 was stock as is the SC and the SC has less body roll and less dive under braking. It also feels easier to catch and control in a slide and some of this goes back to the steering where you can feel every bit of understeer. The power of the 2 cars is pretty comparable with the 964 having more torque. I run 15s on the SC so the power band is never far away and if a fast driver in a 964 or 993 is going to pass me I have to lift.
I think all of this is attributed to the 500 fewer pounds the SC is towing around. To be honest, I don't think I could go back to a 964 or 993 unless I stripped it to an RS-like weight. The body roll was horrendous and weight transfer was pretty scary. The overall experience in terms of feedback and smile factor is higher in the SC for me.
So if you're going to lighten your prospective 993 or 964 I say go for it and you'll have a wonderful car although you will have power steering unless you find the rare RS rack. For a dual purpose car you'll have the option of using adjustable suspension which you can't do in a torsion bar car. Although some people do run 18s on torsion bar cars personally I think they look ridiculous. 18s are easier to run on 993s and were actually verboten by Porsche for the 964 although some do use them anyway. There are certainly more R compound tire choices in the 17 and 18 inch sizes.
The 964 is still the best value in used 911s. The money you could spend to get a great 964 will only buy you a 150K+ mile 993. I realize I've been singing the praises of the non power steering rack but buying an RSA just for that isn't worth it unless money is of no concern. If you're interested in the charm of owning a "special" car then get an RSA. Otherwise spend half the money and get a C2 that you can mod to your delight.
Now if we're comparing creature comforts then the SC doesn't have a chance but that's for another discussion.
Good luck.