grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
hi, which part of the cv joint breaks under extreme stress, for instance a car using slicks with high rpm. thanks grogy
cv weakness
1303Steve Scirocco Rare
8,650 posts · joined Aug 2002 ·
The diff
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
well..... i got a peloquin lsd in an 091, so apparently the cv is the next weak link, i read the offroaders use race prepped cvs usually 930 or 934 cvs. i using kombi cvs, [ i saw an advert for chromemoly cages] will this make any diff for a street strip car. or what is arace prepped cv. or what usually breaks first in a cv
dangerous 23 Windows of Awesome
5,901 posts · joined Jan 2005 ·
The cage is the weakest part of the CV joint.
You can get better cages but I doubt you will need them.
The only time I broke a bus CV was when the axle broke first.
I did have an inner race fail once,
but I had bored out the inside, and resplined them for a larger axle.
You can get better cages but I doubt you will need them.
The only time I broke a bus CV was when the axle broke first.
I did have an inner race fail once,
but I had bored out the inside, and resplined them for a larger axle.
westi wrote:That's mad Alan.
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
apprecaite your experience dave, i dont want to spend any more than i need to..... i put some pics of the trans mounted in the car in teh drag race forum, the ? is, if the trans i slightly out of alignment, will the cvs compensate for this. i dont want to crash the car when i finally get it going cause its not going straight. thanks greg
dangerous 23 Windows of Awesome
5,901 posts · joined Jan 2005 ·
Hi Greg,
you want to try and get the trans aligned as close as possible,
but slight misalignemt wont worry the CVs much.
Just use a level on the bellhousing face ,
and centre the flanges
using the forks and outboard flanges as your reference points.
Your mounting system must be as good as possible.
All the torque reaction off the line tranfers through the mounts.
Forks should be braced up to the cage or shock towers too.
I try to mount under the bellhousing,
under and/or over the intermediate housing,
and also the top of the bellhousing if you have the one with the ears.
you want to try and get the trans aligned as close as possible,
but slight misalignemt wont worry the CVs much.
Just use a level on the bellhousing face ,
and centre the flanges
using the forks and outboard flanges as your reference points.
Your mounting system must be as good as possible.
All the torque reaction off the line tranfers through the mounts.
Forks should be braced up to the cage or shock towers too.
I try to mount under the bellhousing,
under and/or over the intermediate housing,
and also the top of the bellhousing if you have the one with the ears.
westi wrote:That's mad Alan.
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
thanks dave, was tryin to do somewhat that, but not as comprehensive, i get back at it now. appreciate your advice regards greg
vwfastback Seriously Crusin Dubber
187 posts · joined Oct 2003 ·
I thought my axles or Kombi CV's would fail first, but the output shaft of the highdollar diff went first.....
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
vwfastback, what type diff was that, is it in a kombi or ??????????
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
fastback, i checked in search and see u got the turbo car, did i read right and u broke a standard drive shaft in a type 3 trans????????????
matberry Moderator Go hard or go home
8,114 posts · joined Mar 2006 ·
Type one irs box output shaft will break before bus cv's usually imo. Even with the Dangerous mods to retain the cv flange to the output shaft, I broke a few with hard launches and a type I box, I was admitedly using Superboot axles and race prepped/blueprinted type II cv's. Maybe 8000 rpm launches did it ????
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
thanks, from all that i read from dangerous and u , is that the type 2 cvs are quite strong. what did u do to u cvs that makes them race prepped, are they lobro brand
matberry Moderator Go hard or go home
8,114 posts · joined Mar 2006 ·
Yes Lobro and prepped by a dude in Sydney that did big hp formula cars
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
Craig Torrens 6 times Australian, 7 times State Hillclimb Class Champion
8,040 posts · joined Jan 2003 ·
I find that puc clutches kill CV's 😎..............I've never had problems when running a standard style clutch disc, and I do 8000rpm launches all the time !! I think its because the standard disc has just enough give to take the brutal force out of the drivetrain.
vwfastback Seriously Crusin Dubber
187 posts · joined Oct 2003 ·
Nope. Not standard. Racing IRS diff manufactured in Adelaide by what is now Pfitzer gearboxes. Was susposed to be good for 500+ hp.
dangerous 23 Windows of Awesome
5,901 posts · joined Jan 2005 ·
The diameter of your output splines was either type one or 002 I think James,
even though it was a racing type 'torque biasing" diff.
Shame they rated the diff to 500hp.
Any transmission designer worth his salt will rate his parts using a TORQUE figure,
and have a safety margin built in.
You'd possibly have 500hp potential though.👍
I used to crack the type one versions,(never had one fall off though)
and saw the ZF splines crack too....but the small ZF spiders will normally fail first.
In my "twin blower" days even the larger 002 splines used to crack,
but the 091 sized splines did the job.
James, perhaps your diff could be fixed using some 091 splines?
Yes a 3 puc disc is much harsher than full circle disc,
but with the correct pressure plate, 8000 launches (or 8400 by some guys🙄)
can still have a little slip and save parts.
In fact, leaving at MORE RPM can be easier on trans parts than less RPM,
because the extra momentum can induce a little slip, that would not have occured otherwise.
You will be fine with your 091 Greg.
Some companies make the cages from a different material,
but they are generally a little softer, to remove the brittleness.
Mine were dead stock cages.
If you are on a budget, you can polish all the sharp edges of the cage.
You can also have a Heat Treater temper the cages to soften them,
but he may need a material specification.
I think Albins makes cages too....
even though it was a racing type 'torque biasing" diff.
Shame they rated the diff to 500hp.
Any transmission designer worth his salt will rate his parts using a TORQUE figure,
and have a safety margin built in.
You'd possibly have 500hp potential though.👍
I used to crack the type one versions,(never had one fall off though)
and saw the ZF splines crack too....but the small ZF spiders will normally fail first.
In my "twin blower" days even the larger 002 splines used to crack,
but the 091 sized splines did the job.
James, perhaps your diff could be fixed using some 091 splines?
Yes a 3 puc disc is much harsher than full circle disc,
but with the correct pressure plate, 8000 launches (or 8400 by some guys🙄)
can still have a little slip and save parts.
In fact, leaving at MORE RPM can be easier on trans parts than less RPM,
because the extra momentum can induce a little slip, that would not have occured otherwise.
You will be fine with your 091 Greg.
Some companies make the cages from a different material,
but they are generally a little softer, to remove the brittleness.
Mine were dead stock cages.
If you are on a budget, you can polish all the sharp edges of the cage.
You can also have a Heat Treater temper the cages to soften them,
but he may need a material specification.
I think Albins makes cages too....
westi wrote:That's mad Alan.
grogy Custom Title Time!
1,000 posts · joined Aug 2007 ·
fast cars"""""""its can be expensive/frustrating exercise when parts fail, and thats not even including all u time. well i bought some expensive parts for my 091, so hopefully i can be confident it will do the job. i read about 3 diff brands of cv, some from china, and 2 types from germany, lobro and gkn. do u know if gkn & lobro are as good as each other? its an interesting read about all the vws on the forum being built, hope u have urs going again soon vwfastback, im learning all the time. glad to always have your advice dave, save time and money if i start out on the right track. regards greg. ps easier to be reliable if u got n/a car compared to all the turbo ones