...

Go Back   Lateral-g Forums > Technical Discussions > Chassis and Suspension
User Name
Password



Reply
 
Thread Tools Display Modes
  #1  
Old 05-27-2020, 06:19 PM
Tinker's Avatar
Tinker Tinker is offline
Lateral-g Supporting Member
 
Join Date: Apr 2009
Location: Wisconsin
Posts: 264
Thanks: 102
Thanked 75 Times in 48 Posts
Default Real world first Gen F-body front suspension evaluation

Hi all,

I am finally posting this in hopes someone out there can give me factual feedback.

I, like some or many am at a standstill on my project. I got caught up in the scandal a number of years back. (yeah THAT one).
I DO NOT WANT THIS TO BE ABOUT THE PERSON. If this goes off on a tangent I will ask the admin to shut this post down.

What I am looking for feedback from those with experience of front end geometry.

I have all the parts that have been sitting for three or four years now.
I am not worried about the quality of parts. The control arms are from Ridetech, as well as the shocks. The hubs are speedway engineering large hubs with their 3 piece sway bar as well.
The spindles are the fabricated ones which I am almost sure are manufactured by Coleman. The brakes are 14/13 inch Wilwoods.

Before I start cutting as intended, I would like to have some assurance that all my work will not be in vain.

I have all my measurements where I they look good on paper, but has anyone run a similar setup?

Am I going to be alright with 9 deg static caster that will near 12 degrees dynamic in a turn? I would hate to end up with a car that shakes like your local grocery store shopping cart.

Have the fabricated spindles been holding up?

From previous posts it sounds like the shocks should be de-sauced.

I really can't afford to start over, $10,000 in parts is too much to scrap or sell for pennies on the dollar.

I understand these are now dated parts. I am not looking to compete in any large autocrosses or the like.

My goal is to have a car that is fun to drive, reliable and safe to bring out to the track. I would love to be able to do 275's on all corners so tires could be rotated.

I can furnish more parts/setup details if needed.

I thank anyone in advance for their constructive thoughts and advice.
__________________
Chris
1969 Firebird: injected Pontiac 462ci, T56
Reply With Quote
  #2  
Old 05-27-2020, 11:06 PM
Musclerodz's Avatar
Musclerodz Musclerodz is offline
Senior Member
 
Join Date: Nov 2004
Location: washington, ok
Posts: 4,273
Thanks: 22
Thanked 159 Times in 93 Posts
Default

That sounds like alot of caster, but it depends on how low the car sits. I think the new vettes are around 8? but they are LOW. Typically I run around 6 static for street on a first gen with Ridetech kit or DSE sub.
__________________
Mike Redpath
Musclerodz & Customz
facebook page
Reply With Quote
The Following 2 Users Say Thank You to Musclerodz For This Useful Post:
dhutton (05-28-2020), Tinker (05-28-2020)
  #3  
Old 05-28-2020, 05:35 AM
Tinker's Avatar
Tinker Tinker is offline
Lateral-g Supporting Member
 
Join Date: Apr 2009
Location: Wisconsin
Posts: 264
Thanks: 102
Thanked 75 Times in 48 Posts
Default

Quote:
Originally Posted by Musclerodz View Post
That sounds like alot of caster, but it depends on how low the car sits. I think the new vettes are around 8? but they are LOW. Typically I run around 6 static for street on a first gen with Ridetech kit or DSE sub.
Is this due to jacking effect? Do the new vettes only get away with high caster due to the deep offset and low scrub radius?

At 20 degrees steer, outside wheel has neg 7 degrees camber and inside around 4. Will this only wear the tire edges and overwork the power steering?
__________________
Chris
1969 Firebird: injected Pontiac 462ci, T56
Reply With Quote
  #4  
Old 05-28-2020, 07:55 AM
SSLance's Avatar
SSLance SSLance is offline
Senior Member
 
Join Date: Oct 2013
Location: Peoria, AZ
Posts: 2,668
Thanks: 72
Thanked 337 Times in 211 Posts
Default

Chris, as you know I have run a lot of the similar stuff you have for a long time,, and I have beat the wee out if it. I'm certain it will all work out just fine for you. In fact, I wouldn't even worry about revalving the shocks, they'll work great as is. Ridetech, Speedway and Coleman all make tough parts that are on a lot of cars on the road today.

Regarding the geometry, I run 9.75 degrees caster and I love it. The car tracks so well on the road and never once has it been a concern. Tire wear has not been an issue either. It does create a bit of a jacking effect at sharp turn angles but for street driving, you'll only see that pulling into parking spaces and it is not a big deal.

I'm sure once you get it all installed and dial in the alignment, you'll be pleased.

I have un-done some of the sauce we had in my car but that was strictly for on track performance. Those changes did not change the street characteristics much at all.

I say get just, get it all on the car and start enjoying the enhanced performance.
__________________
Lance
1985 Monte Carlo SS Street Car
Reply With Quote
  #5  
Old 05-28-2020, 09:50 AM
SSLance's Avatar
SSLance SSLance is offline
Senior Member
 
Join Date: Oct 2013
Location: Peoria, AZ
Posts: 2,668
Thanks: 72
Thanked 337 Times in 211 Posts
Default

I thought about this further and realized the first gen is a rear steer car which is different than mine. But that still doesn't change my opinion.

I think you should reach out to Rodney Prouty. He knows the first gen stuff as well as anyone and has studied (and tested on track) all types of suspension theory around them. He's also just a great guy willing to help out anyone who is willing to learn.

If you'd like, I can help steer you his direction as he doesn't spend a lot of time in the forums much anymore.
__________________
Lance
1985 Monte Carlo SS Street Car
Reply With Quote
  #6  
Old 05-28-2020, 12:29 PM
Tinker's Avatar
Tinker Tinker is offline
Lateral-g Supporting Member
 
Join Date: Apr 2009
Location: Wisconsin
Posts: 264
Thanks: 102
Thanked 75 Times in 48 Posts
Default

Thanks much Lance. This is what I was looking for. I should have reached out to you knowing your car. I believe you run the corvette style spindles, but geometry is geometry.
What other parts of sauce did you undo?
I know I already ditched the locker.
__________________
Chris
1969 Firebird: injected Pontiac 462ci, T56
Reply With Quote
  #7  
Old 05-28-2020, 06:14 PM
SSLance's Avatar
SSLance SSLance is offline
Senior Member
 
Join Date: Oct 2013
Location: Peoria, AZ
Posts: 2,668
Thanks: 72
Thanked 337 Times in 211 Posts
Default

I still have the locker but I'm looking for an excuse to change it out. It actually worked very well for me until I put the massive front bar in, then I didn't need the pluss of the locker as much and the minuss started to bother me more.

I did have my shocks revalved after having Chris Smith watch my car on a Good Guys course. Chris also showed me a completely different way to adjust my shocks which had an immediate affect on my times.

I also went to a much softer rear spring setup. The big rear spring setup worked fantastic at SCCA style high speed corners but not so much with forward grip on GGs style courses. My tires last twice as long or even longer now and the car is faster.

The geometry is all still pretty much still the same as it has been all along. The contact patch is awesome, I've just changed the speed with which the suspension gets to where it wants to be and how long it stays there. None of that at all affected its street manners, more of a fine tuning for different style tracks.
__________________
Lance
1985 Monte Carlo SS Street Car
Reply With Quote
The Following User Says Thank You to SSLance For This Useful Post:
Tinker (05-28-2020)
  #8  
Old 06-08-2020, 01:39 PM
rickpaw rickpaw is offline
Lateral-g Supporting Member
 
Join Date: Jan 2010
Location: Houston, Tx
Posts: 881
Thanks: 16
Thanked 17 Times in 16 Posts
Default

I think you'll be fine. I have the shocks/springs from him, and besides the front springs be a bit soft (maxed out on my coil over adjustment); and front sway bar interference, it's been fine for my Firebird. I have the shocks/springs/sway bar from him.

So far no issues
__________________
Tu Ho
67 Firebird (aka "Money Pit")-5.3/4l60e, restomod.
https://lateral-g.net/forums/showthread.php4?t=43170

Last edited by rickpaw; 06-08-2020 at 01:41 PM.
Reply With Quote
The Following User Says Thank You to rickpaw For This Useful Post:
Tinker (06-15-2020)
  #9  
Old 06-09-2020, 04:18 AM
Beechy's Avatar
Beechy Beechy is offline
Senior Member
 
Join Date: Nov 2014
Location: Melbourne, Australia
Posts: 258
Thanks: 106
Thanked 95 Times in 68 Posts
Default

Quote:
Originally Posted by Tinker View Post

Am I going to be alright with 9 deg static caster that will near 12 degrees dynamic in a turn? I would hate to end up with a car that shakes like your local grocery store shopping cart.

My goal is to have a car that is fun to drive, reliable and safe to bring out to the track. I would love to be able to do 275's on all corners so tires could be rotated.

I thank anyone in advance for their constructive thoughts and advice.

Chris,
Shopping carts have zero caster, that's why they shake. Having more caster gets you away from that shake but in my experience/opinion 9* is too much in the wet. With reduced grip the tire can't deform enough to stay in full contact so lifts the outside wall (because geometry), you will experience massive push. More so with a wide, low profile tire. I have just gone from 8 to 6 for this reason.
Previously, from a stationary start, I could NEVER flick turn my daily........it would push straight forever. Also giving it gas at low speed around residential blocks (sharp turns) it just pushed.
Factory first gen geometry with upper arm drop and Global West rigid bushing/half height body mounts.....but like u say "geometry is geometry "
__________________
Jim Grant
Melbourne, Australia
(Dual citizen)

Last edited by Beechy; 06-09-2020 at 04:26 AM.
Reply With Quote
The Following User Says Thank You to Beechy For This Useful Post:
Tinker (06-15-2020)
  #10  
Old 06-16-2020, 12:29 PM
Tinker's Avatar
Tinker Tinker is offline
Lateral-g Supporting Member
 
Join Date: Apr 2009
Location: Wisconsin
Posts: 264
Thanks: 102
Thanked 75 Times in 48 Posts
Default

Quote:
Originally Posted by Beechy View Post
With reduced grip the tire can't deform enough to stay in full contact so lifts the outside wall (because geometry), you will experience massive push. More so with a wide, low profile tire. I have just gone from 8 to 6 for this reason. "
Good info.
I imagine this will be the same effect depending on a 300tw, 200tw, or slick. Once I assemble everything I will check how much adjustment I have. Both the frame is slotted and the upper arms are slotted/slugged. Wouldn't be too bad to adjust upper arms depending on conditions or current use. As long as the wheels stay relatively centered in the wheel well for proper clearance.
Checking Temps across the front tires should be a good indicator.
Good notes of tire Temps with conditions should eventually get me where I need to be.
__________________
Chris
1969 Firebird: injected Pontiac 462ci, T56
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 08:21 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright Lateral-g.net