Too EASY to Turn?

[Laser Stan]

OK, I've only got 500 miles in my Mk4, and I'm still learning, but it seems like it's too easy to steer. No, I'm not talking about turning in parking lots; that's a bear. But, on the country roads in medium-tight turns, the steering input doesn't seem to vary with turn radius. In fact, the required steering wheel input torque seems almost constant and light, regardless of the turn radius.

Also, after finishing the turn, I need to turn back to straight line driving, i.e. it doesn't "unwind" on its own. Is this normal? Other manual steering cars that I've had would freely unwind after the turn.

The car tracks straight, there's no bump steer, it's happy at 100 mph (as much as I've dared so far), and nothing else seems unusual.

Caster, camber, and toe are set to the Mk4 book values, 3 deg, -0.5 deg, 1/16", repectively...at least I think so, per my FastTrax. Running Nitto 555s, 245/45 R17, at 26 psi (cold) in the front.

Is something wrong, or should I just leave it alone?

Thanks guys,
Stan

[Mark Reynolds]

Suggest you try more caster and lower your tire pressure.

[edwardb]

3 degrees is the recommended caster for manual steering. It might help to increase, but at the expense of higher effort.

Definitely try lower tire pressure. I run my BFG's at 22 PSI front 245/45/17 and 24 PSI rear 315/35/17, cold. 1500 miles and wear seems fine.

[Cheapsnake]

More caster. I had manual steering and set it up for 3 deg., by the book and had the same results as you. I went to 5 1/2 deg. and it made a world of difference, probably could go to 6. Steering effort increased, but not dramatically. Good luck.

[ZoaFan08]

I had 2* caster and just recently upgraded my sleeves and went to 7* and it feels much better. Not hard but you lose that floating feeling.

[steno]

Originally Posted by ZoaFan08

I had 2* caster and just recently upgraded my sleeves and went to 7* and it feels much better. Not hard but you lose that floating feeling.

What sleeves did you use to vet the extra caster?

[ZoaFan08]

5" sleeve from here.

Aluminum Tie Rod Sleeve, 5/8 Inch - Speedway Motors, America's Oldest Speed Shop

[Laser Stan]

Now, if I can just remember how to use that Fastrax tool.

Thanks, all.

[CraigS]

Now you know why so many of us use power steering. The car feels great w/ 6-8 deg. caster and the PS makes it parkable.

[ZoaFan08]

Originally Posted by CraigS

Now you know why so many of us use power steering. The car feels great w/ 6-8 deg. caster and the PS makes it parkable.

I hated my power steering, the car felt unsafe, but then Jeff told me about the caster and the sleeves and I wouldn't have it any other way. You get the solid feel of manual at speed but still have a soft wheel in parking lots.

[JKleiner]

In addition to more caster 1/16"-3/32" toe in will also help with self centering.

Jeff

[Bob Cowan]

Originally Posted by Laser Stan

Caster, camber, and toe are set to the Mk4 book values, 3 deg, -0.5 deg, 1/16", repectively...at least I think so, per my FastTrax. Running Nitto 555s, 245/45 R17, at 26 psi (cold) in the front.

Is something wrong, or should I just leave it alone?

Thanks guys,
Stan

Those are pretty much the same specs I use for street driving. Except I generally use about 1/32" total toe in. I also use 26psi in the front tires (same tires as you have), and according to the tire temps that seems to be just about perfect. But tire pressures are very dependent on weight.

I also think the steering is light and easy, just the way I like it. Very stable at high speeds, easy to cruise down the highway at 85mph with one hand on the wheel.

Once I get on the twisty mountain roads, there is a little more effort required just as you would expect. But certainly not anything I consider excessive. My car comes back to center pretty easily, and doesn't really need any additional input on my part. Except in a really tight corner at high speed.

I can drive this car through the mountains all day and not get worn out. It takes less effort to drive this car, than it does to ride my Harley. Today I drove about 200 miles in a great variety of situations - and I enjoyed every moment of it.

Originally Posted by ZoaFan08

I had 2* caster and just recently upgraded my sleeves and went to 7* and it feels much better. Not hard but you lose that floating feeling.

I have tried a variety of caster settings, from 1-7*. More caster will return the car to center faster. But it also requires more effort to get it off center. And in a sweeping corner, it requires more effort to keep it from coming back too quickly.

On the track, I find 2.5* to give me the best lap times. Anything more than 4-5* just wears me out. By the end of the day my neck and shoulders hurt so much I end up with a migraine headache.

[JKleiner]

Originally Posted by Bob Cowan

...On the track, I find 2.5* to give me the best lap times. Anything more than 4-5* just wears me out.

Two words Bob:
1. Power
2. Steering



Jeff

[Someday I Suppose]

Keep in mind that the 3 degrees of caster is also the recommendation without the improved SAI position. So on a MKIV complete kit with the FFR Spindles you should be able to run 5 ish without much issue at all. (Manual rack) I think I am at about 4 1/2 right now on my MKIII with the SAI mod and will increase it a little bit more when I get a chance.

-Scott

[cobrajj]

I'm also running 5 degrees caster, 1/16" toe-in with the SAI mod, manual steering on my MK3. Had to install the longer front adj sleeves on the UCA's as I was running out of thread. More effort is required at slow speed, but I wanted the car to be very stable at highway speeds.

[Laser Stan]

What a bunch of great information. It's amazing how close everyone seems to be on this subject. Reducing the front tire pressure by 4 psi did increase the turning feel, but there's still too much "float" in the turns for my taste. So, the next step will be increased caster.

Now, folks, what's the bigger PITA; jacking up and taking the wheels off to get at the linkage or crawling underneath and working cramped and upside down with the wheels on? I'm sure I'll need to do whichever technique more than once. I think I know the answer, but just checking.

[JKleiner]

I leave the wheels on but raise the front to get the weight off.

Jeff

[ZoaFan08]

Originally Posted by Laser Stan

What a bunch of great information. It's amazing how close everyone seems to be on this subject. Reducing the front tire pressure by 4 psi did increase the turning feel, but there's still too much "float" in the turns for my taste. So, the next step will be increased caster.

Now, folks, what's the bigger PITA; jacking up and taking the wheels off to get at the linkage or crawling underneath and working cramped and upside down with the wheels on? I'm sure I'll need to do whichever technique more than once. I think I know the answer, but just checking.

Jack up the car, takes way less time and you'll have less scratched knuckles and not hit your curse word limit for the day.

[sgspeed]

If you put in power steering with a Heidts valve you can set the car up based on parking effort, that is the most effort you can comfortably stand while parking, when you do that the car is a delight to drive and you can crank in as much castor as you want and not have the effort off the chart. I am using 5 degrees. seems good.

I dont think power steering is a luxury or for pussies that cant stand heavy steering. It is all about better performance and a more enjoyable drive. When i built my car the parking effort was so heavy that I could hear the lacquer on the steering wheel crackling from the overstress.