Handling Problems
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Handling Problems
Guys,
I've got a manual steering 84 2.5 in excellent condition. Suspension, shocks, bushes, wheel bearings, steering shaft, tie rods and wishbone balljoints have all been replace in the last 12 months.
Brakes have also been rebuilt. A couple of weeks back the car had a full 4 wheel alignment and felt better than ever....then I replaced the tyres with a set of Kumho Kh15's - 215/60/vr 15's.
Using std pressures 30psi fr and 36psi rear - the steering feels much lighter, even when moving at very low speed. Problem is at anything over 50 mph I've the steering lacks feel - virtually no feedback through the steering wheel - almost feels disconnected from the road..like an overservo'd 1970's Jaguar steering
In the wet it's awful - even worse than in the dry....
Apart from the obvious (ditch the tyres) does anyone have any suggestions
Thanks
Jon
I've got a manual steering 84 2.5 in excellent condition. Suspension, shocks, bushes, wheel bearings, steering shaft, tie rods and wishbone balljoints have all been replace in the last 12 months.
Brakes have also been rebuilt. A couple of weeks back the car had a full 4 wheel alignment and felt better than ever....then I replaced the tyres with a set of Kumho Kh15's - 215/60/vr 15's.
Using std pressures 30psi fr and 36psi rear - the steering feels much lighter, even when moving at very low speed. Problem is at anything over 50 mph I've the steering lacks feel - virtually no feedback through the steering wheel - almost feels disconnected from the road..like an overservo'd 1970's Jaguar steering
In the wet it's awful - even worse than in the dry....
Apart from the obvious (ditch the tyres) does anyone have any suggestions
Thanks
Jon
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The only thing not listed that could, and this is a long shot, effect the steering feel is the upper strut mounts. Other than that.... ditch the tyres.
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Thanks guys,
I'll try experimenting with the pressures this weekend. Also, will order a new set of top mounts (everything else is new so seems a good move whatever the outcome).
Kumho's were great on my 928 wet or dry so I'm struggling to find why they're so bad on the 944...
I'll post the resolve as soon as I've sorted the beast.
Regards
Jon
I'll try experimenting with the pressures this weekend. Also, will order a new set of top mounts (everything else is new so seems a good move whatever the outcome).
Kumho's were great on my 928 wet or dry so I'm struggling to find why they're so bad on the 944...
I'll post the resolve as soon as I've sorted the beast.
Regards
Jon
#6
Drifting
Tires and tire pressures can make HUGE differences. My car regularly changes tires & pressures a few times a weekend, and the difference between 36psi Hoosier A6's and 36psi Kuhmo Escta MX's is almost as big as between a worn stock suspension and a new track suspension.
For that matter, I inadvertently did one lap with 40/36psi vs my normal 36/40psi (switched tires f/r w/o changing pressures)... and had to back WAYYY off because I honestly thought a wheel was falling off or something.
For that matter, I inadvertently did one lap with 40/36psi vs my normal 36/40psi (switched tires f/r w/o changing pressures)... and had to back WAYYY off because I honestly thought a wheel was falling off or something.
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Thanks Scott,
Did you have any issues with the Kumho's? I've used them to good effect on my 928....but they really seem to upset the 944.
Regards
Jon
Did you have any issues with the Kumho's? I've used them to good effect on my 928....but they really seem to upset the 944.
Regards
Jon
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#8
Triple check the sheet from your "four wheel alignment".
Nobody likes to align a 944, and shortcuts have been observed.
If you want, post the sheet here, and we can take a look at it.
You have been describing how a car behaves with toe-out instead of toe-in.
(on your old tires they could have had such a strong wear pattern that the car went straight anyway)
Jay
Nobody likes to align a 944, and shortcuts have been observed.
If you want, post the sheet here, and we can take a look at it.
You have been describing how a car behaves with toe-out instead of toe-in.
(on your old tires they could have had such a strong wear pattern that the car went straight anyway)
Jay
#9
Drifting
FWIW, the RE01-R's are the "king" of the SCCA's "street tire" classes.
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YOu could also try moving tires around (front-back/left-right) and see how that effects things. Sometimes tires with slipping interior belts will feel like an alignment problem.
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Triple check the sheet from your "four wheel alignment".
Nobody likes to align a 944, and shortcuts have been observed.
If you want, post the sheet here, and we can take a look at it.
You have been describing how a car behaves with toe-out instead of toe-in.
(on your old tires they could have had such a strong wear pattern that the car went straight anyway)
Jay
Nobody likes to align a 944, and shortcuts have been observed.
If you want, post the sheet here, and we can take a look at it.
You have been describing how a car behaves with toe-out instead of toe-in.
(on your old tires they could have had such a strong wear pattern that the car went straight anyway)
Jay
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Thanks Guys,
Here are the results :- n.b. the digit before the dot is degrees, the digits after with a ' are minutes.
The alignment was carried out the same morning (just before) the new tyres were fitted.
I booked the alignment after another shop had a go and didn't improve things - booked as "poor handling and light front end"
Been back to the adjusting shop today to have the settings rechecked (all as per below).
FRONT
Caster = L 2.16' R R 2.14'
SAI = L 17.22' R 18.30'
Curve Toe in = L 1 degree dead R 1.19'
Camber angle = L -0.25' R -0.26'
Partial-toe= L .60 R .60
Total toe = 1.30
Set back = 0.28'
REAR
Camber = L -0.38' R -0.54'
Partial toe = L -2.20 R 2.30
Total toe = 0.00
Thrust Angle = -0.18'
set back = 0.28'
Thanks in advance
Regards
Jon
Here are the results :- n.b. the digit before the dot is degrees, the digits after with a ' are minutes.
The alignment was carried out the same morning (just before) the new tyres were fitted.
I booked the alignment after another shop had a go and didn't improve things - booked as "poor handling and light front end"
Been back to the adjusting shop today to have the settings rechecked (all as per below).
FRONT
Caster = L 2.16' R R 2.14'
SAI = L 17.22' R 18.30'
Curve Toe in = L 1 degree dead R 1.19'
Camber angle = L -0.25' R -0.26'
Partial-toe= L .60 R .60
Total toe = 1.30
Set back = 0.28'
REAR
Camber = L -0.38' R -0.54'
Partial toe = L -2.20 R 2.30
Total toe = 0.00
Thrust Angle = -0.18'
set back = 0.28'
Thanks in advance
Regards
Jon
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George Beuselinck recommends this for early 944s. I have had two alignments performed on my 83, manual steering, and I think it's great. I know it's in response to steering shimmy, but it may help you:
If I'm reading correctly, your total toe is 1.3" ? I saw the portion given in degrees-minutes, and another measurement.
I'm also wondering how inflating the tires would make the car less jittery? The garage that installed my tires inflated them to 35 psi. I tried it out on the highway, and it was very nervous. I stick with 29 or 30 in the front.
This street front axle setup works for eliminating the shimmy at 60 mph characteristic in early 944 cars.
Toe: 1/16 inch toe in per side for a total of 1/8 inch toe in.
Camber: -20 minutes +/- 15 minutes
Caster: 2 degrees 30 minutes +30/-15 minutes. If you can go to 3 degrees on both sides, that will make the shimmy go away.
Toe: 1/16 inch toe in per side for a total of 1/8 inch toe in.
Camber: -20 minutes +/- 15 minutes
Caster: 2 degrees 30 minutes +30/-15 minutes. If you can go to 3 degrees on both sides, that will make the shimmy go away.
I'm also wondering how inflating the tires would make the car less jittery? The garage that installed my tires inflated them to 35 psi. I tried it out on the highway, and it was very nervous. I stick with 29 or 30 in the front.
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Hi Joel,
The total toe is shown just as 1.30 on the print out - no degrees or minutes, Partial-toe is the same. All the other readings have a degree and minutes reading against them.
Currently I've kept the pressures at 30/36 as per Porsche recommendations.
Regards
Jon
The total toe is shown just as 1.30 on the print out - no degrees or minutes, Partial-toe is the same. All the other readings have a degree and minutes reading against them.
Currently I've kept the pressures at 30/36 as per Porsche recommendations.
Regards
Jon