Hey guys need your help.
Ok . Ive did a search and havent reall found the answer I'm looking for. I'm ready to set the diff in my project.
http://www.glamisdunes.com/invision/index....howtopic=104718
People say a max off 22 deg angle with a 930cv at full droop. If your flanges are not inline add 1/2 deg for every inch off....Is that correct???
At ride height should'nt the angle be close to the same from the top view as it would from the back at full droop. So the axle doesnt grow in lenght?
How much side to side "plunge" does a axle normally have?
Anyone!
Full Version: Setting Up Cv Angles
22 degrees sounds fine...and yes...add 1/2 -1 deg for each inch offset.....
do you have axles yet ?
with the cv's as CLOSE to each other as possible you should have 1/4-3/8 " free movement of axle...
as the suspension moves down ..limit movement by either cv angle (as above) or axle length ( binding)
up travel should not be an issue on most cars as it will bottom out before cv's max out.....
do you have axles yet ?
with the cv's as CLOSE to each other as possible you should have 1/4-3/8 " free movement of axle...
as the suspension moves down ..limit movement by either cv angle (as above) or axle length ( binding)
up travel should not be an issue on most cars as it will bottom out before cv's max out.....
QUOTE(flattire @ Jun 11 2007, 05:33 PM) [snapback]2327292[/snapback]
22 degrees sounds fine...and yes...add 1/2 -1 deg for each inch offset.....
do you have axles yet ?
with the cv's as CLOSE to each other as possible you should have 1/4-3/8 " free movement of axle...
as the suspension moves down ..limit movement by either cv angle (as above) or axle length ( binding)
up travel should not be an issue on most cars as it will bottom out before cv's max out.....
Thx flattire
I dont have axles yet.
I am trying to figure out if there is a general rule of thumb. As were the diff should mount. How far forward of the drive flanges on the trailing arms? Is at full droop the flanges should be in line vertically looking from the side. At full droop I think its close to 38 deg.I forgot to get a idea of axle growth in lenght. Do I have to split the two and make a happy medium........
Am I making sense?
I would think the "best" location would be where both cv's are equal distance from the cv's near the wheels...(the diff itself would not be centered ..just the inner cv's)
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
When I built my last car I cut an old junk axle in half, slipped a piece of tubing over it and welded a locknut for a bolt on each side. Really helps for setup and getting the right length and clip grooves in the right spot.
If you were in Phoenix you could borrow it.
If you were in Phoenix you could borrow it.
Thanks for you help guys. I think i'll go out a stare at it for awhile.
Good idea "onanysunday" I have a spare junk axle I can do the same with. That way I can cycle it and move it accordingly.
Good idea "onanysunday" I have a spare junk axle I can do the same with. That way I can cycle it and move it accordingly.
ditto the above stuff.
keep the wheel CV and the diff CV aligned vertically at full droop (side view). as mentioned, you won't have CV angle issues at full compression, just axle length issue. if the wheel CV is moving in an arc that starts to the rear of the diff CV at full compression and swings to a point directly below the diff CV at full droop, you're minimizing the length change over the full travel.
looks great, by the way!
keep the wheel CV and the diff CV aligned vertically at full droop (side view). as mentioned, you won't have CV angle issues at full compression, just axle length issue. if the wheel CV is moving in an arc that starts to the rear of the diff CV at full compression and swings to a point directly below the diff CV at full droop, you're minimizing the length change over the full travel.
looks great, by the way!
For the location of the diff. I would put a sraight edge on top of the cv flange on the wheel side and on the diff side and put a jack on the rear arm and a angle finder on the sraight edge and let the wheel side down until it gets to about 26 degrees then place the diff until the axles are sraight or the diff is just barley cheated forward becuase with the wheel at full droop is when the wheel side cv will be closest to the front of the car since the arms move on a arc then you will get the most travel and wheel droop you can with the cvs with out losing angle from cheating the diff to far forward and then they will not bind when the axle is level while compressing, and as for the amount of degrees you can put on the axles I just go by feel once I see the axle start to move in and out while rotating the wheel then I adjust the limit strap a little tighter and make sure nothing is binding so I dont break a cv. Hopefully this is the best way to do it, that is how I have done mine and they have all worked out nice no cv binding or loss of travel or angel good luck.
QUOTE(flattire @ Jun 11 2007, 11:30 PM) [snapback]2327742[/snapback]
I would think the "best" location would be where both cv's are equal distance from the cv's near the wheels...(the diff itself would not be centered ..just the inner cv's)
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
I disagree.
The longest axle is measured from the inside of the CV FLANGES, not the CV. With zero angle and the CV's removed from the car, measure the distance from the inside surfaces of the center of both CV FLANGES. Then subtract about 1/2". And don't assume both sides will be the same! Measure both sides.
ALSO, very important.... when you buy axles, make sure the ends of the axles have a round end, with a ball end. The olders axles that don't have that round end will get beat up as they bang the CV flanges as they plung inward, sometimes hitting the flange. This will smash the clip groove and making things difficult when inspecting CVs, the CV will not want to come off the spline.
The new style with a ball end alleviates the banging of the clip groove and ruining the trueness of the sline. If you want to see a picture of the old style (the type you don't want to buy), look here. You can actually see where the end of my axle got banged up. To take of the CV I had to file out each of the 40+ spline grooves to allow the CV to easily slip off the axles when the c-clip is removed.
Trust me, buy axles with the ball end.
QUOTE(seaduner @ Jun 13 2007, 05:15 PM) [snapback]2330538[/snapback]
QUOTE(flattire @ Jun 11 2007, 11:30 PM) [snapback]2327742[/snapback]
I would think the "best" location would be where both cv's are equal distance from the cv's near the wheels...(the diff itself would not be centered ..just the inner cv's)
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
I disagree.
The longest axle is measured from the inside of the CV FLANGES, not the CV. With zero angle and the CV's removed from the car, measure the distance from the inside surfaces of the center of both CV FLANGES. Then subtract about 1/2". And don't assume both sides will be the same! Measure both sides.
ALSO, very important.... when you buy axles, make sure the ends of the axles have a round end, with a ball end. The olders axles that don't have that round end will get beat up as they bang the CV flanges as they plung inward, sometimes hitting the flange. This will smash the clip groove and making things difficult when inspecting CVs, the CV will not want to come off the spline.
The new style with a ball end alleviates the banging of the clip groove and ruining the trueness of the sline. If you want to see a picture of the old style (the type you don't want to buy), look here. You can actually see where the end of my axle got banged up. To take of the CV I had to file out each of the 40+ spline grooves to allow the CV to easily slip off the axles when the c-clip is removed.
Trust me, buy axles with the ball end.
Filing beat up splines is definitely a pain in the arse.
QUOTE(grporter @ Jun 12 2007, 09:06 PM) [snapback]2329266[/snapback]
ditto the above stuff.
keep the wheel CV and the diff CV aligned vertically at full droop (side view). as mentioned, you won't have CV angle issues at full compression, just axle length issue. if the wheel CV is moving in an arc that starts to the rear of the diff CV at full compression and swings to a point directly below the diff CV at full droop, you're minimizing the length change over the full travel.
looks great, by the way!
QUOTE(2.5king @ Jun 12 2007, 10:29 PM) [snapback]2329318[/snapback]
........and as for the amount of degrees you can put on the axles I just go by feel once I see the axle start to move in and out while rotating the wheel then I adjust the limit strap a little tighter and make sure nothing is binding.
Chopshop, looking at your trailing arm I thought you had a fullsize rail, but since your running the RPM box, I was curious if you were running a MC powerplant or a snowmobile engine. Mostly the snow mobile powered rail guys run the RPM unit, anymore pics of your rail...?
QUOTE(seaduner @ Jun 13 2007, 05:15 PM) [snapback]2330538[/snapback]
QUOTE(flattire @ Jun 11 2007, 11:30 PM) [snapback]2327742[/snapback]
I would think the "best" location would be where both cv's are equal distance from the cv's near the wheels...(the diff itself would not be centered ..just the inner cv's)
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
"best" location would also be where all 4 cv's line up across the vehicle from side to side....this isn't always possible....
the longest axle you can use is determined by the shortest distance between the cv's...with 0 degrees on the axle you will take the distance between the inside of the cv's and subtract 1/4-3/8 " (safety margin).....
I disagree.
The longest axle is measured from the inside of the CV FLANGES, not the CV. With zero angle and the CV's removed from the car, measure the distance from the inside surfaces of the center of both CV FLANGES. Then subtract about 1/2". And don't assume both sides will be the same! Measure both sides.
ALSO, very important.... when you buy axles, make sure the ends of the axles have a round end, with a ball end. The olders axles that don't have that round end will get beat up as they bang the CV flanges as they plung inward, sometimes hitting the flange. This will smash the clip groove and making things difficult when inspecting CVs, the CV will not want to come off the spline.
The new style with a ball end alleviates the banging of the clip groove and ruining the trueness of the sline. If you want to see a picture of the old style (the type you don't want to buy), look here. You can actually see where the end of my axle got banged up. To take of the CV I had to file out each of the 40+ spline grooves to allow the CV to easily slip off the axles when the c-clip is removed.
Trust me, buy axles with the ball end.
!/2 inch is'nt always enough. If you have two bushings on you rear arms it definatly is'nt enough. The length of the axle does not set the amount of travel and angle on you c-v's, how far apart and the the c-v's are from each other and the set back do that. Once the car is built there is no reason to "stuff" the longest axle you can between the c-v cups because if the car is built properly you will run out of c-v angle before axle length.3/4 to 1 inch and you wont be fileing splines.
Because your arms pivot points are straight you may be limited to only u-joint type axles. The reason is the arms will not travel in a arc relative to the flanges if viewed from the rear, they will only go straight up and down which makes the length of the axles at droop and bump a lot longer. This may over extend the cvs and cause binding/clip damage or both.
QUOTE(yoshi @ Jun 14 2007, 05:48 AM) [snapback]2331197[/snapback]
QUOTE(grporter @ Jun 12 2007, 09:06 PM) [snapback]2329266[/snapback]
ditto the above stuff.
keep the wheel CV and the diff CV aligned vertically at full droop (side view). as mentioned, you won't have CV angle issues at full compression, just axle length issue. if the wheel CV is moving in an arc that starts to the rear of the diff CV at full compression and swings to a point directly below the diff CV at full droop, you're minimizing the length change over the full travel.
looks great, by the way!
QUOTE(2.5king @ Jun 12 2007, 10:29 PM) [snapback]2329318[/snapback]
........and as for the amount of degrees you can put on the axles I just go by feel once I see the axle start to move in and out while rotating the wheel then I adjust the limit strap a little tighter and make sure nothing is binding.
Chopshop, looking at your trailing arm I thought you had a fullsize rail, but since your running the RPM box, I was curious if you were running a MC powerplant or a snowmobile engine. Mostly the snow mobile powered rail guys run the RPM unit, anymore pics of your rail...?
Great topic. Yoshi, i think you mixed up your number here.
dont forget about back angle you need to add that to your angle too.acc 1/2 of the back angle added to the down angle as a service factor though cause angle is angle wether its up down or back ,and conside what kind of car you can a vw car at 28 deg but if you run a v8 car your going to break parts so 22 is better than 28 and straight as they were designed would even be better. so say 10 deg back /2 is 5 deg and 26 down -5 back is 21deg .and the axel lenght isnt always shortest at staight accross .mess at werever it is thought the travel less the 1/4 inch clearence and then hope its long enough at the 21 deg that you dont pull the cv apart. and you dont get all three ..axel to long or short and or deg to much when you get one you have to stop. .now think about tire hight and what a diff that will make ..boy that was easy
QUOTE(Sick Dayz @ Jun 14 2007, 08:14 AM) [snapback]2331546[/snapback]
QUOTE(yoshi @ Jun 14 2007, 05:48 AM) [snapback]2331197[/snapback]
QUOTE(grporter @ Jun 12 2007, 09:06 PM) [snapback]2329266[/snapback]
ditto the above stuff.
keep the wheel CV and the diff CV aligned vertically at full droop (side view). as mentioned, you won't have CV angle issues at full compression, just axle length issue. if the wheel CV is moving in an arc that starts to the rear of the diff CV at full compression and swings to a point directly below the diff CV at full droop, you're minimizing the length change over the full travel.
looks great, by the way!
QUOTE(2.5king @ Jun 12 2007, 10:29 PM) [snapback]2329318[/snapback]
........and as for the amount of degrees you can put on the axles I just go by feel once I see the axle start to move in and out while rotating the wheel then I adjust the limit strap a little tighter and make sure nothing is binding.
Chopshop, looking at your trailing arm I thought you had a fullsize rail, but since your running the RPM box, I was curious if you were running a MC powerplant or a snowmobile engine. Mostly the snow mobile powered rail guys run the RPM unit, anymore pics of your rail...?
Great topic. Yoshi, i think you mixed up your number here.
yerp,...I mean a 24" long strap if you need a 26" long strap, that way it can extend the 2" to what you need as it stretches......
QUOTE(dbbob @ Jun 14 2007, 12:16 PM) [snapback]2332005[/snapback]
dont forget about back angle you need to add that to your angle too.acc 1/2 of the back angle added to the down angle as a service factor though cause angle is angle wether its up down or back ,and conside what kind of car you can a vw car at 28 deg but if you run a v8 car your going to break parts so 22 is better than 28 and straight as they were designed would even be better. so say 10 deg back /2 is 5 deg and 26 down -5 back is 21deg .and the axel lenght isnt always shortest at staight accross .mess at werever it is thought the travel less the 1/4 inch clearence and then hope its long enough at the 21 deg that you dont pull the cv apart. and you dont get all three ..axel to long or short and or deg to much when you get one you have to stop. .now think about tire hight and what a diff that will make ..boy that was easy
Exactly!!!
QUOTE(dbbob @ Jun 14 2007, 12:16 PM) [snapback]2332005[/snapback]
dont forget about back angle you need to add that to your angle too.acc 1/2 of the back angle added to the down angle as a service factor though cause angle is angle wether its up down or back ,and conside what kind of car you can a vw car at 28 deg but if you run a v8 car your going to break parts so 22 is better than 28 and straight as they were designed would even be better. so say 10 deg back /2 is 5 deg and 26 down -5 back is 21deg .and the axel lenght isnt always shortest at staight accross .mess at werever it is thought the travel less the 1/4 inch clearence and then hope its long enough at the 21 deg that you dont pull the cv apart. and you dont get all three ..axel to long or short and or deg to much when you get one you have to stop. .now think about tire hight and what a diff that will make ..boy that was easy
correct
QUOTE(lardass @ Jun 14 2007, 05:52 PM) [snapback]2332719[/snapback]
QUOTE(dbbob @ Jun 14 2007, 12:16 PM) [snapback]2332005[/snapback]
dont forget about back angle you need to add that to your angle too.acc 1/2 of the back angle added to the down angle as a service factor though cause angle is angle wether its up down or back ,and conside what kind of car you can a vw car at 28 deg but if you run a v8 car your going to break parts so 22 is better than 28 and straight as they were designed would even be better. so say 10 deg back /2 is 5 deg and 26 down -5 back is 21deg .and the axel lenght isnt always shortest at staight accross .mess at werever it is thought the travel less the 1/4 inch clearence and then hope its long enough at the 21 deg that you dont pull the cv apart. and you dont get all three ..axel to long or short and or deg to much when you get one you have to stop. .now think about tire hight and what a diff that will make ..boy that was easy
correct
Im a little confused here.... Why would you subtract the back angle #'s ?? 26-5 ?.
Wouldnt it make more sense to add the back angle # to the other # making it 31 degrees total in the above equation ???....
.
So after reading all this !!
This is my plan. I am able to mount the diff so all the cv's line up all across the vehicle from side to side at full droop. the axle angle will be approx 38 degs. Since the are lined up there won't be a back angle to add.
So I'm going to talk with Jess at Hi Angle for u-joint axles. A race prep cv is ony good for like 28 deg. right ? I'm guessing at around $120 ea. ? I think the u-joints are good up too 38 degs. and the axle growing in lenght will not be a problem. If that is the case. From full comp. to full droop on the coilover is 18.5 inches of wheel travel. After I bump and strap it I should be good for 17in. +/-.
Thats the plan ! Thx everyone
This is my plan. I am able to mount the diff so all the cv's line up all across the vehicle from side to side at full droop. the axle angle will be approx 38 degs. Since the are lined up there won't be a back angle to add.
So I'm going to talk with Jess at Hi Angle for u-joint axles. A race prep cv is ony good for like 28 deg. right ? I'm guessing at around $120 ea. ? I think the u-joints are good up too 38 degs. and the axle growing in lenght will not be a problem. If that is the case. From full comp. to full droop on the coilover is 18.5 inches of wheel travel. After I bump and strap it I should be good for 17in. +/-.
Thats the plan ! Thx everyone
I like that plan- Jess
QUOTE(tsanchez @ Jun 14 2007, 07:58 AM) [snapback]2331507[/snapback]
Because your arms pivot points are straight you may be limited to only u-joint type axles. The reason is the arms will not travel in a arc relative to the flanges if viewed from the rear, they will only go straight up and down which makes the length of the axles at droop and bump a lot longer. This may over extend the cvs and cause binding/clip damage or both.
Yes . My Tatum car was straight so I copied that design. After everything was welded and done. I was cycling the arms it hit me and I realized why some were angled.
I thought too late now. I 'll chock it up to lesson learned on this project.
tell Jess you know me, maybe he'll only double the price!
j/k! one driveshaft and multiple axles from Jess and I have nothing but great things to say about him, personally or professionally. No one has handled my business in a more professional, personal or respecful manner.
BTW, keep the build pics and details coming.
j/k! one driveshaft and multiple axles from Jess and I have nothing but great things to say about him, personally or professionally. No one has handled my business in a more professional, personal or respecful manner.
BTW, keep the build pics and details coming.
QUOTE(chopshop @ Jun 14 2007, 09:43 PM) [snapback]2333151[/snapback]
QUOTE(tsanchez @ Jun 14 2007, 07:58 AM) [snapback]2331507[/snapback]
Because your arms pivot points are straight you may be limited to only u-joint type axles. The reason is the arms will not travel in a arc relative to the flanges if viewed from the rear, they will only go straight up and down which makes the length of the axles at droop and bump a lot longer. This may over extend the cvs and cause binding/clip damage or both.
Yes . My Tatum car was straight so I copied that design. After everything was welded and done. I was cycling the arms it hit me and I realized why some were angled.
I thought too late now. I 'll chock it up to lesson learned on this project.The reason that most reputable builders build The 9 degree angle into there chassis trailing arms is for cornering/ turning ... in hard turns !. its all relative when your just putting about the dunes.... But when your on it in the turns... Push comes to shove !!!.
.
QUOTE(swark @ Jun 14 2007, 10:02 PM) [snapback]2333208[/snapback]
QUOTE(chopshop @ Jun 14 2007, 09:43 PM) [snapback]2333151[/snapback]
QUOTE(tsanchez @ Jun 14 2007, 07:58 AM) [snapback]2331507[/snapback]
Because your arms pivot points are straight you may be limited to only u-joint type axles. The reason is the arms will not travel in a arc relative to the flanges if viewed from the rear, they will only go straight up and down which makes the length of the axles at droop and bump a lot longer. This may over extend the cvs and cause binding/clip damage or both.
Yes . My Tatum car was straight so I copied that design. After everything was welded and done. I was cycling the arms it hit me and I realized why some were angled.
I thought too late now. I 'll chock it up to lesson learned on this project.The reason that most reputable builders build The 9 degree angle into there chassis trailing arms is for cornering/ turning ... in hard turns !. its all relative when your just putting about the dunes.... But when your on it in the turns... Push comes to shove !!!.
.
isnt thier more sway with angle built into the trailing arms wouldnt straight arms reduce body roll for better handling?
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