69 911 handling/steering question

[robertmark]

The shocks are not comfort. Does the vr rating give you a stronger sidewall as opposed to the r rated tires I have on now? I don't want to go to larger rims or too many mods, as I'm trying to keep the car a survivor. Perhaps front sway bar and new vr tires?

[Larmo63]

Bigger wheels may help your handling issues and, sway bars are not that hard to install?

Those 14" wheels are kind of the red headed step child of Fuchs. Your car would look better with 15s IMHO.

[robertmark]

Originally Posted by Larmo63

Bigger wheels may help your handling issues and, sway bars are not that hard to install?

Those 14" wheels are kind of the red headed step child of Fuchs. Your car would look better with 15s IMHO.

Agree on the red headed step child, but I want to keep car original. All fuchs including spare are date stamped correctly and original to the car. Maybe I'll go slightly wider tire with vr rating instead of r rated.

[burgermeister]

You could try staggering tire pressure more if you're not already doing so. More in the rear, little less in the front.

If you switch tires, keep the fronts narrow and change to wider ones just in the rear. Try to pick summer performance tires - the bigger the tread blocks the better. The 14" might limit you there. If you don't plan many miles, so wear is not a major concern, you could get the rears shaved a bit. Basically you want the rear stiffer and the front softer, laterally.

What is your driving experience? A few track days with an old 911 will be a total hoot, and will also help train your hands to make inputs at appropriate input speeds and coordinate properly with the throttle. This doesn't help the car, but it helps you, and you, along with your senses, reflexes, and feedback, are a big part of the system.

[robertmark]

Originally Posted by burgermeister

You could try staggering tire pressure more if you're not already doing so. More in the rear, little less in the front.

If you switch tires, keep the fronts narrow and change to wider ones just in the rear. Try to pick summer performance tires - the bigger the tread blocks the better. The 14" might limit you there. If you don't plan many miles, so wear is not a major concern, you could get the rears shaved a bit. Basically you want the rear stiffer and the front softer, laterally.

What is your driving experience? A few track days with an old 911 will be a total hoot, and will also help train your hands to make inputs at appropriate input speeds and coordinate properly with the throttle. This doesn't help the car, but it helps you, and you, along with your senses, reflexes, and feedback, are a big part of the system.

Yes, I have track experience in both an 88 targa, and a 06 997. Man you learn a lot when you get on a track with a good instructor. As much body roll as I'm experiencing with the current set up on the 69, don't think I'll be hitting the track.

[1979-930]

^^^ Yea no need for tracking that car. Looks like a cool classic touring car.


Sent from my iPhone using Tapatalk

[robertmark]

Thanks Derrick, this is my countryside cruiser. I won’t be tracking, but wouldn’t mind a bit more anti roll up front.

[cassisrot]

Is your car a 1969 E? If so does it still have it's hydro pneumatic struts? If not, what were they replaced with?

[Bill Verburg]

Originally Posted by robertmark

So I'm new to the early 911's. Only had the car on the road for maybe the tenth time when I had to swerve abruptly left, then right to avoid hitting something in the road. The car felt loose so I experimented at about 50 mph moving the steering wheel quickly between say 11 and 1 o'clock. You can feel the body of the car rolling , as I would call it. When I did the same thing in my 89 911, it just darts in the direction you point it, and you don't feel this rolling/bobbing effect. Is this normal for an early 911, to have this effect I'm experiencing? I don't know if I need to check something on the car, or if this is just the way the earlier cars handle. Thanks!!

The difference between a stock '60 and stock '89 is immense

The issues you are asking about will be traced to the wheels, tires and sways(assuming that all else is at least nominal)
'60 5.5 x14 w/ unspecified but likely 185/78 x14 tires and no sways vs a
6x16 205/55 & 8x16 225/50

The feel and response if the car is directly correlated to the pneumatic coefficient of the tires which is derived form the tire construction, geometry and pressures and from the wheel specs. A 185/78 or even 185/70 on a 5.5 x14 will have much more flexible sidewall and tread compared to either of the comparable wheel/tire sets on the '89, the 185 will run at a much higher slip angle( the whole tire twists and is distorted) and will as a result be capable of far lower inputs to the chassis vectors. What you will feel is a lazy, sloppy response compared to the later set ups, all else being equal, the '89 can be made sharper yet by judicious tuning. The other large influence is the sway bars which have a significant effect on chassis roll and thus on on camber gain or loss which also has a significant effect on grip and response. All 911s even your '89 have a lot of roll w/ a stock suspension compared to a truly sporting setup.


a '69 T was designed as a comfortable tourer not as a sporting vehicle, the '89 is still a comfortable tourer but is also a much more capable sporting vehicle

[robertmark]

Originally Posted by cassisrot

Is your car a 1969 E? If so does it still have it's hydro pneumatic struts? If not, what were they replaced with?

Correct, it is an E. Not sure what brand my guy installed. But I know they're new.

[robertmark]

Originally Posted by Bill Verburg

The difference between a stock '60 and stock '89 is immense

The issues you are asking about will be traced to the wheels, tires and sways(assuming that all else is at least nominal)
'60 5.5 x14 w/ unspecified but likely 185/78 x14 tires and no sways vs a
6x16 205/55 & 8x16 225/50

The feel and response if the car is directly correlated to the pneumatic coefficient of the tires which is derived form the tire construction, geometry and pressures and from the wheel specs. A 185/78 or even 185/70 on a 5.5 x14 will have much more flexible sidewall and tread compared to either of the comparable wheel/tire sets on the '89, the 185 will run at a much higher slip angle( the whole tire twists and is distorted) and will as a result be capable of far lower inputs to the chassis vectors. What you will feel is a lazy, sloppy response compared to the later set ups, all else being equal, the '89 can be made sharper yet by judicious tuning. The other large influence is the sway bars which have a significant effect on chassis roll and thus on on camber gain or loss which also has a significant effect on grip and response. All 911s even your '89 have a lot of roll w/ a stock suspension compared to a truly sporting setup.


a '69 T was designed as a comfortable tourer not as a sporting vehicle, the '89 is still a comfortable tourer but is also a much more capable sporting vehicle

Thanks Bill I'm running 185/70r14's. What would help as far as tires are concerned? I want to stay with the factory stock rims which are 14's. Can I go with the same tire size but with a vr instead of an r? Does that make any difference, or, do I need to go slightly taller or wider, or both?

Car drives straight, brakes straight, but if you're on the highway at speed and you make a sudden swerve for any reason, LOOK OUT!!!!You are likely to become a passenger. Thanks for all input!!

[Bill Verburg]

Originally Posted by robertmark

Thanks Bill I'm running 185/70r14's. What would help as far as tires are concerned? I want to stay with the factory stock rims which are 14's. Can I go with the same tire size but with a vr instead of an r? Does that make any difference, or, do I need to go slightly taller or wider, or both?

Car drives straight, brakes straight, but if you're on the highway at speed and you make a sudden swerve for any reason, LOOK OUT!!!!You are likely to become a passenger. Thanks for all input!!

using a 6" wheel vs the 5.5 would stiffen the tire a bit as will raising tire pressures, the caveat w/ pressures is you loose grip if you go too far.

The easiest thing for you to do is to get a set of f/r sway-bars, 15/15 from a '72-73 would help tame body roll a lot, Back in the day we added them to bar less T's , the better kits back then were from H&H Carrera but that was 50yrs ago

[latunabernie]

I have a 1970 T with comfort package
I am running 185 75 14 Tiger Paws
Tire psi F 29 rear 31
I added a 15mm through the frame sway bar.
It changed the car.
Car is stable at high speeds, but front end gets light feeling.
Car does blow around on windy days.
I had the problems you are talking about.
Went to a really good alignment that knows Porsches. Solved the problem.
Your latter 911 is heavier and has lot more rubber on the ground.
You can't compare them.
Also check the age of your tires.

Bernie

[robertmark]

Thanks guys, think I'll start with higher tire pressure. No improvement's I'll go to front sway bar. Does anyone know if the vr rating gets you a stronger sidewall over an r rating?

Latunabernie, do your tiger paws have a r or vr rating? Thanks guys

[latunabernie]

Hi Robert,
The Uniroyal tiger paws are a M&S all season tire.
89S rating range B 4 ply.
When I wear these out I will be going to the new classic Pirelli.
14" tires have very limited choices. unless you want trailer tires.
My car came with 14" Fuchs. I plan on keeping them.

Bernie

[robertmark]

Originally Posted by latunabernie

Hi Robert,
The Uniroyal tiger paws are a M&S all season tire.
89S rating range B 4 ply.
When I wear these out I will be going to the new classic Pirelli.
14" tires have very limited choices. unless you want trailer tires.
My car came with 14" Fuchs. I plan on keeping them.

Bernie

Hello Bernie,

What tire size are you going with on the classic Pirelli? When I look up the correct size for my car, 185/70/14 the only tire that is sufficient is the Vredestein sprint classic. All five of my 14" fuchs are original and matching date stamped. I don't want to change my rim sizes.

[Arne2]

The correct (original) size for your car is NOT 185/70-14. It was 185HR14, which in today's nomenclature is equivalent to 185/80-14.

There are only three tires in the correct size that are (or claim to be) for use on classic sports cars.

The original size of 185HR14 is available in the Vredstein Sprint Classic (available from several vendors), or the Michelin MXV-P (available from Coker). I'm not crazy about either one as being a true performance tire, but of those 2 I'd go with the Michelin. I've heard too many people complain about soft sidewalls and sloppy handling with the Vredsteins.

There is now an additional choice - 185/80HR14 in the Dunlop Sport Classic (available from Coker). I've not heard/seen many reports on this tire yet, but the few I have heard have been good. The Dunlop is actually made in Europe by Goodyear, and the tread looks a whole lot like the old Eagle NCT/Eagle GT/Wingfoot tires from the late '70s and early '80s. It might be a good choice.

[robertmark]

Originally Posted by Arne2

The correct (original) size for your car is NOT 185/70-14. It was 185HR14, which in today's nomenclature is equivalent to 185/80-14.

There are only three tires in the correct size that are (or claim to be) for use on classic sports cars.

The original size of 185HR14 is available in the Vredstein Sprint Classic (available from several vendors), or the Michelin MXV-P (available from Coker). I'm not crazy about either one as being a true performance tire, but of those 2 I'd go with the Michelin. I've heard too many people complain about soft sidewalls and sloppy handling with the Vredsteins.

There is now an additional choice - 185/80HR14 in the Dunlop Sport Classic (available from Coker). I've not heard/seen many reports on this tire yet, but the few I have heard have been good. The Dunlop is actually made in Europe by Goodyear, and the tread looks a whole lot like the old Eagle NCT/Eagle GT/Wingfoot tires from the late '70s and early '80s. It might be a good choice.

Thanks Arnie, I currently have Michelin defenders which carry exactly the same specs as two of the tires you mentioned. The Vredstein is the only tire that carries a higher speed rating. Wouldn't it seem that would make the sidewalls stronger?

[Arne2]

Originally Posted by robertmark

Thanks Arnie, I currently have Michelin defenders which carry exactly the same specs as two of the tires you mentioned. The Vredstein is the only tire that carries a higher speed rating. Wouldn't it seem that would make the sidewalls stronger?

No, sidewall stiffness is only part of the equation. The Defender is not a performance tire. It's an all-season tire suitable for mini-vans. I was not aware that it could be found in the original, correct, non-70 series size. But in any case it is not a tire I would recommend to anyone as a sporty tire suitable for this type of car.

There is a lot more to tire suitability for a particular purpose than just size or specs or sidewall height/stiffness. You need to look at true, performance rated sports car tires. Which are admittedly hard to find in a suitable size for the 14" wheels.

[Arne2]

One additional thought - Remember that the 14" wheel option was sold as part of the Comfort package. So even the best of performance tires that were available back in the day were not going to handle as well as the 15" options - the 14" were supposed to be softer. I totally understand wanting to retain the original 14" wheels, which is why I'd strongly consider the new Dunlop in size 185/80HR14 if I were you.

But due to the small wheel size, and the "comfort" aspect of that, you might be happier with 15" wheels and tires.