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Mr.Primer
10-09-2009, 11:21 AM
Hi all.
This will be my first post in here and it will be about a problem i have on my Firebird-67.
The problem makes me not wanna drive my car and this sux.
The car was restored in late 80's by me and have a original front end.
The problem is handling in highway speed. In every minor bump or so in the road the car moves sideless and feels very inaccurate. The front end have new ball joints, control arm bushings, new end links for swaybar. The springs are Firebird 400 original. The things i dont have replaced are pitman arm and steering gear. The pitman arm are a little worn, but imo not too much.
I've tried to differ toe in/out without any luck. Caster/camber im not to sure of. The tires are worn mostly on the outer side.

Anyone have a clue?
sry for my english, i have some problems with the technical terms :)

Ops i forgot, the body mounts are all new

Yoda4561
10-09-2009, 12:06 PM
It sounds like a caster angle problem. You're probably not running enough positive caster for highway stability. I'm not well versed in practical wheel alignment, so can't help on the how's and whats of fixing it.

eville
10-09-2009, 12:33 PM
Modern alignment specs first
Check Pozzi's site
Then, upgrade steering box with new pitman and rag joint.
What tire sizes are you running?

Lowend
10-09-2009, 12:48 PM
It's sounding like either bad alignment or a bump-steer issue.

Take it in for a 3-dimensional (toe, castor and camber) alignment before you do anything else.

Mr.Primer
10-09-2009, 03:24 PM
thx for replies. :)
i'm also into wheel alignment problems so i think i'll go for a totally overhaul in that part.
i'm driving 205/60/15 in front.
Think i'll dive into my books and get updated in the caster/camber/toe in /toe out world :)
Mayby a replace of the pitman arm would be appropriate to since it doesnt feel 100%.

JRouche
10-09-2009, 05:41 PM
Ill second the caster recommendation. A lil more pos caster will also help with bump steer slightly. JR

ks71z28
10-10-2009, 10:47 AM
Darty over bumps is a toe out issue likely, but beware, 1st gens came with lots of different steering arm and front end configurations. I had one with 2 different length steering arms! 1st gens stock handle poorly, but don't do what you say unless there is an issue. Shoot for 1/8 toe in, 2-3 deg castor is ALL you can hope for, and 1/2 deg neg camber. If you do stock settings you won't be happy. How sloppy is steering box? Also although it was rebuilt, I have seen wrong parts installed, so if it has been 20 years, maybe it is time to do it again and right for piece of mind

David Pozzi
10-10-2009, 11:49 AM
Use the alignment specs on my web page. More negative camber will reduce tire edge wear and more positive caster will help the car track better on the freeways.

Get a faster ratio firm feel PS box, yours is likely worn. It goes without saying all your front end components need to be in top shape: idler arm, pitman arm, tie rod ends, balljoints, A arm bushings, Steering box, wheel bearings, shocks. Even tire condition and matching types is important. A rear suspension problem or uneven wheel weights can also cause instability.
You can adjust the top screw on the box to see if that helps, but the valving will still be soft.

Mr.Primer
10-11-2009, 04:45 AM
thx guys for all good respons, i will dig in to this and se if i can come out with a more fun car to drive :)