justbob
02-17-2014, 06:28 AM
I think mine is well within the limits but before I throw any more money at this car I am wanting to confirm. My trans is -4* driveshaft around -1* and the pinion is right at +2*. The working angle I believe would be -4* minus -1* equalling -3* front ujoint, and the rear being +2* plus +1* equalling +1*
I have read up on soooo many conflicting ways of setting this properly! I am to understand I am looking for matching - and + numbers first, then factor in -1* to -2 1/2* at the rear for torque to raise the pinion in four link applications. That science would put me dead nuts where it should be.
My trans output shaft is dead on within an 1/8" of stock, ujoints are 2 1/2" farther apart, but overall driveshaft length is a tad shorter. (No slip joint/flange to flange application)
I have talked to Rick at Metco (before digging in in my angles) and he suggested look into this and also an upgrade to Delrin bushings may be in order as the manual is simply too hard on the regular ones.
I'm limited on trans adjustment as it will only raise 1/8" and I'm hitting the tunnel, but I am not opposed to sending out the upper arms to be made adjustable. Still not seeing the need though.
I think all my problems would be solved using the GT500 CV shaft offered by DSS. They quoted me around $850 for the aluminum but in my set up critical speed limited to around 130 or their carbon fiber for $1,450 critical speed around 190 MPH. Keep in mind I would like to enter the Chicago 1/2 mile someday, part of the reason I chose a six speed and set this car up the way I have. BUT right now is not the best time financially for all this as I have made too many big purchases lately, Christmas bills, and was slow at work the last six weeks. So I may have to put this in hold for a spell, the car is just fine up to 70 as is. DSS assured me just going to aluminum would put a stop to most vibrations, but also insisted I check my angles.
If you can offer assistance then I'm all ears.
Things you should know.
The car and shaft can take ridiculous amounts of torque off the line or at speed.
It always starts vibrating on new shafts around 80 to 105 under WOT, then worsens over time, so more speed related.
First shaft lasted the longest and Srg Mac hit 122 with zero problems. I hit 100 a few times, 115 at the track first run, shattered it in half and threw parts at the new M3 as I passed in third at 90. :D
Second shaft didn't feel right at 80, had a different shop balance it. On the way to Atlanta I hit 105 and caused another vibration at anything over 80, had realigned yet again in Atlanta and can feel it at 70 now, actually the car felt different after they did it at all speeds.. I did watch them and it looked good to me, but I know squat..
I think half my battle is dealing with cromoly steel and rotational mass?
Hopefully that gives enough info, thanks again.
Self proclaimed Builder Of Badassery.
Buy it, Break it, Build it BETTER.
"Since 2004"
I have read up on soooo many conflicting ways of setting this properly! I am to understand I am looking for matching - and + numbers first, then factor in -1* to -2 1/2* at the rear for torque to raise the pinion in four link applications. That science would put me dead nuts where it should be.
My trans output shaft is dead on within an 1/8" of stock, ujoints are 2 1/2" farther apart, but overall driveshaft length is a tad shorter. (No slip joint/flange to flange application)
I have talked to Rick at Metco (before digging in in my angles) and he suggested look into this and also an upgrade to Delrin bushings may be in order as the manual is simply too hard on the regular ones.
I'm limited on trans adjustment as it will only raise 1/8" and I'm hitting the tunnel, but I am not opposed to sending out the upper arms to be made adjustable. Still not seeing the need though.
I think all my problems would be solved using the GT500 CV shaft offered by DSS. They quoted me around $850 for the aluminum but in my set up critical speed limited to around 130 or their carbon fiber for $1,450 critical speed around 190 MPH. Keep in mind I would like to enter the Chicago 1/2 mile someday, part of the reason I chose a six speed and set this car up the way I have. BUT right now is not the best time financially for all this as I have made too many big purchases lately, Christmas bills, and was slow at work the last six weeks. So I may have to put this in hold for a spell, the car is just fine up to 70 as is. DSS assured me just going to aluminum would put a stop to most vibrations, but also insisted I check my angles.
If you can offer assistance then I'm all ears.
Things you should know.
The car and shaft can take ridiculous amounts of torque off the line or at speed.
It always starts vibrating on new shafts around 80 to 105 under WOT, then worsens over time, so more speed related.
First shaft lasted the longest and Srg Mac hit 122 with zero problems. I hit 100 a few times, 115 at the track first run, shattered it in half and threw parts at the new M3 as I passed in third at 90. :D
Second shaft didn't feel right at 80, had a different shop balance it. On the way to Atlanta I hit 105 and caused another vibration at anything over 80, had realigned yet again in Atlanta and can feel it at 70 now, actually the car felt different after they did it at all speeds.. I did watch them and it looked good to me, but I know squat..
I think half my battle is dealing with cromoly steel and rotational mass?
Hopefully that gives enough info, thanks again.
Self proclaimed Builder Of Badassery.
Buy it, Break it, Build it BETTER.
"Since 2004"