a arm questions

[1977nova]

I know this idea might be very stupid but I was thinking for a cheap fix to the upper a arms hitting the wheel at full turn with wheels with alot of backspace, would be to just trim back the outer edges of the arm. I also thought if that weakened the a arm what you could do is bend up some round bar that fits inside the a arms and just weld it in. would this just be similar in strength to a tubular a arm? I just think there could be a much simpler way of fixing that problem other than buying new a arms. dont get me wrong though I like tubular a arms but they just seem to be really expensive unless you want all the of suspension mods that come with it. I am not building a race car and I believe I can just set up my stock suspension to satisfy my needs.

[baz67]

The problem with adding tubing is that you add unsprung mass. You want to try and avoid that.

[astroracer]

anything you add that is inboard of the a-arm pivots is "sprung" mass... The tire/wheel and brake corner are unsprung and the shock/spring mass is usually divided in half.
Mark

[wally8]

Typically half of the a-arm mass would be considered unsprung as well.


Wally

[David Pozzi]

I think it would work but you need to be sure there is clearance to the subframe, and of course the welding must be a high quality job. There are also circle track tubular uppers available pretty cheap for that subframe.

[1977nova]

Where would I be able to find them for my car. I am just having trouble finding parts

[pav8427]

any time you can 'box' something it will be stronger.
thin walled tube and 12 or 14 ga. sheet metal would pay for itself in the long run.
the only problem with the circle track arms is that the cheap ones are steel on steel for bushings.

doug

[baz67]

anything you add that is inboard of the a-arm pivots is "sprung" mass... The tire/wheel and brake corner are unsprung and the shock/spring mass is usually divided in half.
Mark

Yes, and the control arms are outside of the pivot points. Wally is correct in that half the weight is spung, but it still adds half of the added weight to unsprung mass. You still want to avoid adding any unsprung mass if you can. If adding that mass is something that nova is willing to live with than that is fine. I like the way he is thinking out of the box to solve his problem.

[1977nova]

well I was thinking of cutting the outside steel off where that lip was so the added weight wouldnt be so much. I will get a picture of what im thinking so everyone could understand what my idea is.

[1977nova]

here are some pics. I thought I can cut off the two outside lips and box it in from underneath. since round bar is used in tubular a arms I figured that that would work. Maybe boxing them in with flat steel is all thats needed. plus I see the benifits of being able to use a wide range of control arm bushings and the fact it would look stock.

[David Pozzi]

http://www.speedwaymotors.com/prod_l...eptSearch_id=2

$42.95 each!
I used the Guldstrand solid steel upper bushings on my 67 and they lasted a long time. All the early GM pickups used steel on steel upper and lower bushings. Of course I'd rather have delrin bushings. The speedway web page doesn't say what the bushing material is.

There is no guarantee the above arms are more narrow than your stock arms though.

Is your photo your actual 77 Nova upper Arm? I thought they were the same as second gen Camaro. ???
David

[1977nova]

its just a photo of a camaro arm. I just used it for reference thats all. will steel bushings be too hard, I plan on driving the car everyday and some of the roads around here are quite rough. I just thought I could use rubber bushings. how much maintainance is needed with steel bushings? I wanted to use rubber because I dont want to have to keep lubing poly ones.

[David Pozzi]

You wouldn't notice going with steel upper bushings and they would be great if you were not driving a lot of miles on bumpy roads, but if you are going to rack up a lot of miles, I'd use the stock type rubber bushings, and I agree polly is a pain.

If you modify your upper arms, weld on the new tube inside, before you cut off the outer lips. That will reduce distortion. The tube would have to be seamless.

[1977nova]

Would it be noticable with both solid upper and lower bushings? I plan on running 15x8 wheels up front with 265/50 tires. I am thinking maybe by using 15's this would reduce the amount of harshness.

[79T/Aman]

I'm running solid steel bushings uppers and I put over 70,000 miles on the car as long as you grease them they'll be fine and you wount tell any extra harshness because the arm moves more freely thus not transferying harshness, and I run 780# springs and del-alums in the lowers ( 79 t/a )

[David Pozzi]

We have Del-A-Lum on my wife's 73 Camaro and you wouldn't know it by riding in it.
One thing with 15" wheels is there are very few really good DOT open track or autocross competitive tires available in that rim size. You can still get normal street tires though.

The 16" and 17" tires are shorter profile but lighter weight, so there is some tradeoff that helps the larger rim sizes keep up with the 15" on ride quality.

[79T/Aman]

I'm still runing 15" and the available tire is almost none existant all I can find for the street is M&S type tires , 440 treadwear (way too hard) but I did want to max out the handling with 15" but I'v come to a brick wall there!

[1977nova]

well it looks like I am leaning towards the del-a-lum bushings. the steel ones are half the price but I think they wouldnt last as long though and would be more maintainace.

[David Pozzi]

I've got four BFG Comp TA R1 265X50XZR15" brand new with full tread, (5/32"), not shaved, never mounted. This is their road race tire, but it has a tread pattern and is not as soft as their autocross tire, if interested let me know. I've decided to go with a larger rim dia.

The steel will last quite a while but I can't say just how long. I put 20,000 miles or so on my uppers from Guldstrand and they are still OK.