Front left suspension gremlin
05-26-2017, 01:36 PM
#1
Front left suspension gremlin
The car 2004 RX8 sport suspension full cage built to SCCATouring 4 specs.
Ran the car in a driving school (first time on track) 3rdsession pushed hard and overheated trans. Notchy, Clutch grabby, wheels andbrakes so hot we couldn’t get pressures.Session 4 on warm up turning left at about 40mph got a thud, thud ,thudfrom the left front.Immediately thoughtbrakes.I continued and after the 3rdlap completely cleared up.5thsession went out for warm up and was paying close attention and once again thudthud thud but much worse.I didn’t touchthe brakes and on the in-car you can hear it and see the impact on myself whenit pushes me forward when it happens.Clearly not just a sound.Butonce again gone after 3rd lap and up to temps.Thought hub maybe?But no indication nothing obvious atall.Next week changed to Mazda speedspring, pulled out hawk blue pads from the rears and installed stock addedmore toe out in the front.Went to atrack day at Milwaukee mile and the only real left hander is a double apex 4thgear 85 to 95 MPH.So quite nervous thefirst couple of times thru.The issuewas still there but at the higher speeds it was less noticeable but neverreally went away and the sound was moreof a Brrr, Brrr Brrr instead.I wasconsidering just changing hubs but I’m having a hard time believing they have aproblem.Hubs are tight smooth and don’tget hot at all.ABS hub sensor maybe?Hard to believe they wouldn’t have a failsafefor this.Any ideas please.
Ran the car in a driving school (first time on track) 3rdsession pushed hard and overheated trans. Notchy, Clutch grabby, wheels andbrakes so hot we couldn’t get pressures.Session 4 on warm up turning left at about 40mph got a thud, thud ,thudfrom the left front.Immediately thoughtbrakes.I continued and after the 3rdlap completely cleared up.5thsession went out for warm up and was paying close attention and once again thudthud thud but much worse.I didn’t touchthe brakes and on the in-car you can hear it and see the impact on myself whenit pushes me forward when it happens.Clearly not just a sound.Butonce again gone after 3rd lap and up to temps.Thought hub maybe?But no indication nothing obvious atall.Next week changed to Mazda speedspring, pulled out hawk blue pads from the rears and installed stock addedmore toe out in the front.Went to atrack day at Milwaukee mile and the only real left hander is a double apex 4thgear 85 to 95 MPH.So quite nervous thefirst couple of times thru.The issuewas still there but at the higher speeds it was less noticeable but neverreally went away and the sound was moreof a Brrr, Brrr Brrr instead.I wasconsidering just changing hubs but I’m having a hard time believing they have aproblem.Hubs are tight smooth and don’tget hot at all.ABS hub sensor maybe?Hard to believe they wouldn’t have a failsafefor this.Any ideas please.
05-26-2017, 03:29 PM
#3
My gently tracked 07 6 spd auto got to doing that Brr, Brr, BRR on left front.
It would seem that the traction control is going off.
When I did last alignment, the tech got the front right caster to around 4.9 instead of around the normal 6.5 deg or whatever, also, I told him to set at minimal toe out.
Also, I think the weak rear suspension is allowing the right rear to go low which jacks up the front left.
I also lost wheels weight on that wheel which could maybe influence trouble.
I now have the Bilstein B12 and Michelin PSS which plants car, but I haven't tested on track.
I only have 33k miles on 8, and have tracked maybe 12 times +; I just now changed the rear brake pads which wear quicker than front on my stock brakes.
The fronts are about half worn, and I'll watch for new ones.
Fastest on track was 96mph, and I chirped the Exsta Spt tires while slowing.
Track day is not a race, so go easier on brakes. RX8 needs to retain all the speed it caN around corners.
Leave it to the BMW guys that can use hp to compensate for bad driving, and keep the momentum in the RX8.
It would seem that the traction control is going off.
When I did last alignment, the tech got the front right caster to around 4.9 instead of around the normal 6.5 deg or whatever, also, I told him to set at minimal toe out.
Also, I think the weak rear suspension is allowing the right rear to go low which jacks up the front left.
I also lost wheels weight on that wheel which could maybe influence trouble.
I now have the Bilstein B12 and Michelin PSS which plants car, but I haven't tested on track.
I only have 33k miles on 8, and have tracked maybe 12 times +; I just now changed the rear brake pads which wear quicker than front on my stock brakes.
The fronts are about half worn, and I'll watch for new ones.
Fastest on track was 96mph, and I chirped the Exsta Spt tires while slowing.
Track day is not a race, so go easier on brakes. RX8 needs to retain all the speed it caN around corners.
Leave it to the BMW guys that can use hp to compensate for bad driving, and keep the momentum in the RX8.
Last edited by 40w8; 05-26-2017 at 03:37 PM.
06-05-2017, 08:24 AM
#5
Sorry for the formatting I can't edit for some reason.
40w8, I think you are right about the TCS. I run with it on and will notice it has gone off and will stay off (TCS off light) then look down and its back on. It still amazes me how little time you have to look at the gauges when at speed.
I run another time trial at Milwaukee this weekend and will run with TCS off. I'll also be on slicks (Hoosier R7's) for the first time ever! Wish me luck.
40w8, I think you are right about the TCS. I run with it on and will notice it has gone off and will stay off (TCS off light) then look down and its back on. It still amazes me how little time you have to look at the gauges when at speed.
I run another time trial at Milwaukee this weekend and will run with TCS off. I'll also be on slicks (Hoosier R7's) for the first time ever! Wish me luck.
08-08-2017, 02:19 PM
#6
Just an update
So while at the track struggling with this left brake issue(in between races) I did some research with a bunch of Miata guys (some used torun the 8) and the consensus was disable the DSC. The advice was all the same and the easiestway is to disable was to flip the yaw meter upside down and default thecomputer.For a track car it’s probably finebut for a full Race car it is not.The carwas amazing after doing this!No moretraining wheels but it was so erratic it about put me off track several timesanyway.