Norval, A arms
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Norval, A arms (gkull)
Next winter I would be glad to modify your spindles but for the cross shafts that can be done right now. I would do it if you sent me a pair of cross shafts or course you must remove the A arms for shipping but any machine shop can mill the groves in 5 minutes with the A arms attached.
The 1/4 inch slot allows 5 degrees with only 1 shim. Mill it to 3/8th and the shim would dissappear.
I know you can stiffen the front end up but what happens to the ride over normal rough roads. You are pounding the rest of the car. I can take railroad tracks at a good clip without feeling any pounding and I don't want to shake my car too much. I hate a hard ride. Guess I am getting too old for rough rides. I even have my horse stuffed with hay for a smooth ride :)
I don't know the difference a few degrees Caster makes but with 5 I am happen and the car tracks straight, no pulling and yet low speed cornering with the power steering is fine.
My car does move around too much on take off and cornering but the wife at least will ride with me. That is a good thing. :)
The 1/4 inch slot allows 5 degrees with only 1 shim. Mill it to 3/8th and the shim would dissappear.
I know you can stiffen the front end up but what happens to the ride over normal rough roads. You are pounding the rest of the car. I can take railroad tracks at a good clip without feeling any pounding and I don't want to shake my car too much. I hate a hard ride. Guess I am getting too old for rough rides. I even have my horse stuffed with hay for a smooth ride :)
I don't know the difference a few degrees Caster makes but with 5 I am happen and the car tracks straight, no pulling and yet low speed cornering with the power steering is fine.
My car does move around too much on take off and cornering but the wife at least will ride with me. That is a good thing. :)
Race Director
Joined: Nov 2000
Posts: 16,416
Likes: 1
From: NC,USA
Re: Norval, A arms (norvalwilhelm)
Could we slot the a-arm attachment point and slide them backwards? To get the AC cobra effect... might have to rework the spindles... at least the top part closest to the upper a-arm!
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Norval, A arms (ZD75blue)
Could we slot the a-arm attachment point and slide them backwards?
Isn't that what I did. I slottd the cross shaft holes where they bolt to the frame and slid them back to gain caster. It was a simple 5 minute job to mill the holes into slots. I did make spacer to take up the rest of the slot so there is not chance of loosing the settings.
Isn't that what I did. I slottd the cross shaft holes where they bolt to the frame and slid them back to gain caster. It was a simple 5 minute job to mill the holes into slots. I did make spacer to take up the rest of the slot so there is not chance of loosing the settings.
Instructor
Joined: May 2001
Posts: 228
Likes: 0
From: Santa Cruz CA
Re: Norval, A arms (norvalwilhelm)
Take a look at these adjustable upper control arms. All the castor you need. No shims or milling.
http://www.polepositionrp.com/select.htm
I installed a pair of these, you can ream the spindle and use the beefy threaded ball joint shown, or a stock ball joint or a tall mono-ball and effectively increase spindle height. I also took this opportunity to lower the upper a-arm mounting point on the chassis. So now I increased camber in roll and as much castor as I need.
I also measured my bump steer. Even with VBP bump steer elimator (which lowers the outer tie rod about 5/8"), I have a measurable amount of bump, so it needs to be lower still. Haven't fixed this yet - maybe an extended stud and high-quality rod ends - make my own tie-rods.
http://www.polepositionrp.com/select.htm
I installed a pair of these, you can ream the spindle and use the beefy threaded ball joint shown, or a stock ball joint or a tall mono-ball and effectively increase spindle height. I also took this opportunity to lower the upper a-arm mounting point on the chassis. So now I increased camber in roll and as much castor as I need.
I also measured my bump steer. Even with VBP bump steer elimator (which lowers the outer tie rod about 5/8"), I have a measurable amount of bump, so it needs to be lower still. Haven't fixed this yet - maybe an extended stud and high-quality rod ends - make my own tie-rods.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Norval, A arms (68427)
Those are the same style ones as GregP has, speedway motors and others carry them too. The problem with these is, they look kind of flimsy if you ask me. What has me worried the most is they use heim joints and they wear rather quickly.
Hold on... just looked at them. These look a lot sturdier than the others I've seen.. hmm... These are from speedway motors:
I like these, they even are available w/ mounting for mini balljoints. The dodge ball joints require reaming of the spindle and a tool to install them.
[Modified by Twin_Turbo, 10:56 AM 5/13/2003]
Hold on... just looked at them. These look a lot sturdier than the others I've seen.. hmm... These are from speedway motors:
I like these, they even are available w/ mounting for mini balljoints. The dodge ball joints require reaming of the spindle and a tool to install them.
[Modified by Twin_Turbo, 10:56 AM 5/13/2003]
Instructor
Joined: May 2001
Posts: 228
Likes: 0
From: Santa Cruz CA
Re: Norval, A arms (Twin_Turbo)
How to lower upper a-arm mount:
I used the Pole Position a-arm that looks exactly like the one in lower picture posted above, a very sturdy piece. Rather than have a custom drilled cross-shaft, I took out my stock locating studs and redrilled the holes lower using the new cross-shaft as a template. Then I welded hardened washers to the backside to securly locate the new a-arm bolts.
Option 2. I read this in an old race car prep book. Cut the a-arm mounting tabs from the frame. Slice an inch out and reweld the now lower mounts to frame. Still have to use washers/shims for alignment, though.
I used the Pole Position a-arm that looks exactly like the one in lower picture posted above, a very sturdy piece. Rather than have a custom drilled cross-shaft, I took out my stock locating studs and redrilled the holes lower using the new cross-shaft as a template. Then I welded hardened washers to the backside to securly locate the new a-arm bolts.
Option 2. I read this in an old race car prep book. Cut the a-arm mounting tabs from the frame. Slice an inch out and reweld the now lower mounts to frame. Still have to use washers/shims for alignment, though.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Norval, A arms (68427)
68427 Those are nice A arms but slotting the stock cross shafts 1/4 inch costs next to nothing and makes 5 degrees positive Caster easy with little shimming.
As for moving the roll center lowering the inner A arm mount is great but it involves cutting the stock mount which is also easy but not with the motor in the car. It is an old camaro trick to cut the mount off , reduce it's height, move it back 3/4 inch and reweld. With the motor in the car that is too difficult. If my motor was out I would do it.
Slotted stock A arms takes care of the caster but we need longer spindles and I believe that properly cut, use a donor spindle for the extension and rewelding is the answer but I am not ready to touch the car again until next winter.
Bump steer is also a problem which I intend to play with soon. The weather is not that nice and I am just getting the yard in shape with planting and getting the sprinkler systems up and running.
Nice arms
Norval
As for moving the roll center lowering the inner A arm mount is great but it involves cutting the stock mount which is also easy but not with the motor in the car. It is an old camaro trick to cut the mount off , reduce it's height, move it back 3/4 inch and reweld. With the motor in the car that is too difficult. If my motor was out I would do it.
Slotted stock A arms takes care of the caster but we need longer spindles and I believe that properly cut, use a donor spindle for the extension and rewelding is the answer but I am not ready to touch the car again until next winter.
Bump steer is also a problem which I intend to play with soon. The weather is not that nice and I am just getting the yard in shape with planting and getting the sprinkler systems up and running.
Nice arms
Norval
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Norval, A arms (norvalwilhelm)
68427 , I like these arms, they are just what the doctor prescribed ;)
Do you know what they cost? Couldn't find a price list on that page. I like these much bettter than the speedway motors ones.
Do you know what they cost? Couldn't find a price list on that page. I like these much bettter than the speedway motors ones.
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Le Mans Master
Joined: Nov 2000
Posts: 8,220
Likes: 208
Re: Norval, A arms (Twin_Turbo)
68427 , I like these arms, they are just what the doctor prescribed ;)
Do you know what they cost? Couldn't find a price list on that page. I like these much bettter than the speedway motors ones.
Do you know what they cost? Couldn't find a price list on that page. I like these much bettter than the speedway motors ones.
Race Director
Joined: Nov 2000
Posts: 16,416
Likes: 1
From: NC,USA
Re: Norval, A arms (groovyjay)
then don't read it ;) :crazy: :lol:
I like the adjustable a-arm... looks like something i could fab. 5 years later, yep learned how to weld... got suspension programs for testing... now its time to build it! Hey why didnt i just slot the a-arm like norval said? Woulda saved alot of learning!
:leaving:
Instructor
Joined: May 2001
Posts: 228
Likes: 0
From: Santa Cruz CA
Re: Norval, A arms (Twin_Turbo)
Here is a link to the supplier with the good a-arms http://www.polepositionrp.com
I think I paid a little over $100 ea. for them and they are nicely made except I would recommend changing out the hardware to bolts with close tolerance shanks. Also, I used a mono-ball in lieu of an upper ball-joint because it is taller and height adjustable (no need to modify spindle). Note that since these do not have big urethane or rubber bushings, they will be noisier than stock - but much more accurate.
Another bonus - they look great
I think I paid a little over $100 ea. for them and they are nicely made except I would recommend changing out the hardware to bolts with close tolerance shanks. Also, I used a mono-ball in lieu of an upper ball-joint because it is taller and height adjustable (no need to modify spindle). Note that since these do not have big urethane or rubber bushings, they will be noisier than stock - but much more accurate.
Another bonus - they look great
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Norval, A arms (ZD75blue)
Just in case someone missed my picture of the slotted A arms. This is a simple 1/4 inch 7/16th slot added to the existing hole and a simple spacer to take up the unwanted clearnace. It allows 5 degrees caster easily. It is also a 5 minute job for anyone with a mill and the A arms do not need to be taken apart.
Double click on the picture to blow up.
[Modified by norvalwilhelm, 1:28 PM 5/14/2003]
Double click on the picture to blow up.
[Modified by norvalwilhelm, 1:28 PM 5/14/2003]
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Norval, A arms 69427
I'm sold..... * looking for credit card * .....
I may get the screw in ball joints too if they don't require reaming the spindle. What part # do you have? What length (close to stock?)
I may get the screw in ball joints too if they don't require reaming the spindle. What part # do you have? What length (close to stock?)
