Rear end wagging
11-05-2018, 09:47 AM
#16
Three Wheelin'
Check your control arms. I bet your shop forgot to tighten after set up or they came loose. If you don't have it, tarett sells a locking toe arm kit.
Changing toe will give the feeling you describe. Happened to me once, ruined a track weekend
Changing toe will give the feeling you describe. Happened to me once, ruined a track weekend
11-05-2018, 10:15 AM
#17
Rennlist Member
Will pull the wheels off and take a closer look at the bushings tomorrow.
Ill play around with the tire pressures also. Still very new to this car, so wanted to try it as Porsche intended it...
.
Any thoughts on worn engine mounts?
Thankfully Black Friday sales are coming soon...
Ill play around with the tire pressures also. Still very new to this car, so wanted to try it as Porsche intended it...
.Any thoughts on worn engine mounts?
Thankfully Black Friday sales are coming soon...
solid mounts are nice but quite “loud” for the street.
11-05-2018, 12:04 PM
#18
Nordschleife Master
Thread Starter
Will take pics of the tail pipes when I get home. I did notice the passenger side looks just slightly lower. Mounts are easy enough to do, so maybe a good first step.
Also found Gadsby’s post on the worn thrust arms.
Replacing the dog bones and thrust arms with all OEM rubber is about $1k in parts. Makes me wonder if I should go down the slippery slope of adjustable everything... 😏
Also found Gadsby’s post on the worn thrust arms.
Replacing the dog bones and thrust arms with all OEM rubber is about $1k in parts. Makes me wonder if I should go down the slippery slope of adjustable everything... 😏
11-05-2018, 08:00 PM
#21
I agree with DHI. If alignment, LSD and parts are good working order. When tracking these cars they are sensitive to high hot rear tire pressures. I can always tell my rear tire pressures are too high when my rear moves around under heavy braking. Bringing the pressures down to my known hot pressure always resolves this issue. Good luck.
11-05-2018, 09:42 PM
#22
Nordschleife Master
Thread Starter
Dropped the tire pressure to 32/35. Will try and go for a drive tomorrow and see if that did the trick.
Pulled the drivers rear off, noting looks amiss. Did some probing with a pry bar on some of the dog bones, nothing out of the ordinary. Visual check of the thrust arm and control arm bushings, all looks good.. but still not going to rule that out. Also did a quick check of various nuts and bolts, all are tight. Will pull the passenger off tomorrow and do the same.
I also jacked the car up just a little by the engine and saw no movement of the engine before the entire car started lifting, so i think that rules out the engine mounts. Pictures of the tail pipe are pretty subjective based on where i position the camera.
Pulled the drivers rear off, noting looks amiss. Did some probing with a pry bar on some of the dog bones, nothing out of the ordinary. Visual check of the thrust arm and control arm bushings, all looks good.. but still not going to rule that out. Also did a quick check of various nuts and bolts, all are tight. Will pull the passenger off tomorrow and do the same.
I also jacked the car up just a little by the engine and saw no movement of the engine before the entire car started lifting, so i think that rules out the engine mounts. Pictures of the tail pipe are pretty subjective based on where i position the camera.
11-05-2018, 11:22 PM
#23
Racer
Those tail pipes are lower than on my car - BUT if the rear mufflers have ever been off the car for any reason, the final re-positioning may have been & bolted up hanging lower, as there is a small up / down adjustment on the pipes when the securing bolts are loosened.
Determining wear or looseness on the suspension components can be difficult. Jacking up one side only and using a pry bar to determine worn parts is next to impossible. Both wheels need to be "hanging" on the suspension, but even then, bushes on drop links and control arms usually require pulling them off their respective contact suspension component to feel for any looseness. I chased rattling worn out front LCA bushes for months, replacing drop links, steering rods and upper shock mounts before removing the control arms and finding the bushes very loose in the housing...….. This wear did not show up while the LCA's were still attached to the rest of the suspension. The difference in suspension compliance after the LCA's were changed out was significant, not only noise but in suspension improvement too.
Posting your alignment specs would have given everybody a better understanding too, so perhaps another shop can set up the suspension to (say) Kussmaul base settings which in turn could save you a lot of time down blind alleys....
Determining wear or looseness on the suspension components can be difficult. Jacking up one side only and using a pry bar to determine worn parts is next to impossible. Both wheels need to be "hanging" on the suspension, but even then, bushes on drop links and control arms usually require pulling them off their respective contact suspension component to feel for any looseness. I chased rattling worn out front LCA bushes for months, replacing drop links, steering rods and upper shock mounts before removing the control arms and finding the bushes very loose in the housing...….. This wear did not show up while the LCA's were still attached to the rest of the suspension. The difference in suspension compliance after the LCA's were changed out was significant, not only noise but in suspension improvement too.
Posting your alignment specs would have given everybody a better understanding too, so perhaps another shop can set up the suspension to (say) Kussmaul base settings which in turn could save you a lot of time down blind alleys....
11-06-2018, 08:00 PM
#24
OTOH, With all due respect the OP has only driven the car 200 miles if I understand, and he doesn't even know how the car handles.
11-07-2018, 02:05 PM
#25
Still getting used to this car, have about 200 miles on it so far. 57k miles (no track), brand new PS2's in stock sizes and fresh off the scales from a corner balance / alignment / bump steer. The front and rear toe links were replaced with spherical. Transmission mount is the updated 997 part, has 15k miles on it.
Ive noticed a bit of a unsettling characteristic from the rear. If you lift while turning, i can feel the car yaw / or pull slightly in the direction i am turning. I know... 'no lift'. But you can feel it even on long sweeping turns on the highway, not just driving it through the canyons. Once it 'settles'. it feels nice and planted.
Ive had cars with both worn and good LSD's and don't recall ever feeling this behavior. Is this what a worn out diff on a GT3 feels like? I am thinking of going Guards rebuilt sooner rather than later now.
Any other ideas? Engine mounts? Rubber elsewhere in the suspension? Tire squirming? I think realistically this will stay a street car for me, so i don't really want to go spherical everything.
Its one hell of a car though!
Ive noticed a bit of a unsettling characteristic from the rear. If you lift while turning, i can feel the car yaw / or pull slightly in the direction i am turning. I know... 'no lift'. But you can feel it even on long sweeping turns on the highway, not just driving it through the canyons. Once it 'settles'. it feels nice and planted.
Ive had cars with both worn and good LSD's and don't recall ever feeling this behavior. Is this what a worn out diff on a GT3 feels like? I am thinking of going Guards rebuilt sooner rather than later now.
Any other ideas? Engine mounts? Rubber elsewhere in the suspension? Tire squirming? I think realistically this will stay a street car for me, so i don't really want to go spherical everything.
Its one hell of a car though!
Good luck with your car. They are amazing once you get them dialed in and learn how to drive them.
11-07-2018, 09:53 PM
#26
Nordschleife Master
Thread Starter
Not new to rear engine; i have an '88 Carrera as well.
Tire pressure change did not help. Something else i was thinking was to swap the rear wheels left to right...maybe this weekend. But like i said, this issue existed before the new tires, so i don't think that will help.
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy. One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.
On the bright side, i did figure out what the rattling sound between 2200-2500 rpm was. The common muffler tips rattling on the pipe issue. I wedged a copper washer between the tip and pipe that got rid of the rattle. Ill do a more elegant solution with aluminum or copper sheet.
Tire pressure change did not help. Something else i was thinking was to swap the rear wheels left to right...maybe this weekend. But like i said, this issue existed before the new tires, so i don't think that will help.
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy. One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it
. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.On the bright side, i did figure out what the rattling sound between 2200-2500 rpm was. The common muffler tips rattling on the pipe issue. I wedged a copper washer between the tip and pipe that got rid of the rattle. Ill do a more elegant solution with aluminum or copper sheet.
Last edited by Techno Duck; 11-07-2018 at 10:23 PM.
11-08-2018, 03:37 AM
#27
RL Community Team
Rennlist Member
Rennlist Member
Monoballs are awesome on these cars. My road GT3 had monoballs everywhere and it felt more communicative in some ways than my cup car does which has the factory rubber bushings in most places. Yes a bit of clunking and clacking but not that bad on a GT3 compared to other cars I've experienced. Worth it IMO!
11-08-2018, 08:18 AM
#28
Rennlist Member
If you don't mind a little more road noise and harshness over bad roads, the RSS semi-solid mounts really tighten up the car.
It just depends how sensitive you are to these things. For me it's no big deal. I cut my teeth on Triumph TR-4as when I got out of high school.
The difference between Armstrong lever shocks and solid steel plates is indistinguishable.
It just depends how sensitive you are to these things. For me it's no big deal. I cut my teeth on Triumph TR-4as when I got out of high school.
The difference between Armstrong lever shocks and solid steel plates is indistinguishable.
11-08-2018, 11:49 AM
#29
Not new to rear engine; i have an '88 Carrera as well.
Tire pressure change did not help. Something else i was thinking was to swap the rear wheels left to right...maybe this weekend. But like i said, this issue existed before the new tires, so i don't think that will help.
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy. One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.
On the bright side, i did figure out what the rattling sound between 2200-2500 rpm was. The common muffler tips rattling on the pipe issue. I wedged a copper washer between the tip and pipe that got rid of the rattle. Ill do a more elegant solution with aluminum or copper sheet.
Tire pressure change did not help. Something else i was thinking was to swap the rear wheels left to right...maybe this weekend. But like i said, this issue existed before the new tires, so i don't think that will help.
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy. One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it
. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.On the bright side, i did figure out what the rattling sound between 2200-2500 rpm was. The common muffler tips rattling on the pipe issue. I wedged a copper washer between the tip and pipe that got rid of the rattle. Ill do a more elegant solution with aluminum or copper sheet.
11-08-2018, 11:50 AM
#30
Chasing red herrings? Just rebuild the LSD
Not new to rear engine; i have an '88 Carrera as well.
Tire pressure change did not help. ,,,,
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy..... One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.
Tire pressure change did not help. ,,,,
Still trying to get the alignment numbers... will stop by the shop this weekend. Also i have a local friend with a 6-GT3 that i am going to meet up with.
Because the motor mounts are so easy to remove i pulled them off out of curiosity. Not sure what these should look like new, but the passenger side sags about 2mm more than the drivers. Will plan to replace these, just need to decide do i stick with OEM or go semi-solid.
..
All new dog bones, control arms and torque arms will run $1600 from Sunset. Could rebuild my control arms with Elephant Racing rubber bushings for $400 vs $674 for new..assuming my ball joints are still good. Spherical everything would be nice, but i've ruined my fair share of street cars by turning them into street / track cars.
Guards LSD will run about $1500-2000 at my local indy..... One selling point of this car was 'never been tracked'. If i'm going through all this $ and trouble...ill probably track it
. The price was right and i know any old car i buy will need some sorting out. I always wanted one of these, so just extremely excited to have it in the garage.Save your money for future repairs.
Only replace the plates in the LSD, The ramps are unnecessary.