VetteMOD.com

VetteMOD.com (http://www.vettemod.com/forum/index.php)
-   Chassis, Steering and Suspension (http://www.vettemod.com/forum/forumdisplay.php?f=9)
-   -   C6 front suspension measurements needed (http://www.vettemod.com/forum/showthread.php?t=11746)

Boomstick33 11-19-2020 04:05 PM

C6 front suspension measurements needed
 
Here's my dilemma: I'm building a custom frame for a two seater sports car & want to use the front suspension (upper/lower control arms & steering knuckle) from a C6. I'm looking for specific measurements from the stock setup, namely the measurements of the mounting points on the cradle & frame relative to each other and if possible the relative position of the center of the wheel and the orientation of said mounting points relative to probably the ground to give me the proper geometry. Normally, I have a few different people I work with on things like this but Covid shot all of that down. I work with Covid positive patients (I'm a PT in skilled nursing) so I can't have my usual help around. If anyone has the numbers, or can assist me in getting them I'd greatly appreciate it. I saw in the downloads section here that there's numbers for C5 front suspension but not C6. Now I've read & have had people say that the front upper/lower control arms & mounting positions are the same in the C5 & C6 and can interchange plus the geometry between the two front suspensions are the same, although the steering racks are different and mount differently. If that's true, then I should be able to use that information then.

BBShark 11-19-2020 07:50 PM

C5 and C6 LCA & UCA are the same front and rear. The track width and wheel base could be adjusted obviously for your design. The thing that you will have to guess at are Center of Gravity and Roll Center, F/R weight distribution etc.

rtj 11-19-2020 11:30 PM

Not sure if you would want them, but someone sells a prefab cradle for C6 suspension front and rear. If I remember correctly it was a bit bulky, so may not be of interest. I think I saw them on racingjunk.com. And, someone may have posted photos here.

Superbuickguy just did c5 front suspension, but you probably have seen that thread. If not, check it out.

phantomjock 11-20-2020 11:57 PM

And I have a pair of the C7 uprights that have been "molested"-- BUT IN A GOOD WAY. The upper ball joints have been pressed-out and a sleeve inserted. This lets you choose an extended ball joint to work camber change. The lowers have been reamed for 6141 ball joints - a more common BJ from circle track racing.
If you are planning on using the "stock" GM upper and lower control arms - forget about these.

But--if you are thinking of designing your own, they could be very useful. They still take the GM/SKF bearing. The C7 uprights are much lighter than the earlier C5/6 uprights, GM learned a lot about strength to weight and changed their castings. This image is not of mine - but representative. [Only registered and activated users can see links. Click Here To Register...]

I'm going to full race mode and my suspension is now all rod ends.

I would let these go for less than what they cost from GM Parts Direct (they had the best price) and no charge for the machining. In fact I'd make a deal for Black Friday too! (need to get them off my shelf!)

Sounds like a real cool project. Look forward to seeing the plan/layout and pictures of the build too!

Cheers - Jim

Boomstick33 12-18-2020 04:06 AM

Let me think about it...I currently have all the C6 & even all of the C5 components that I need...it's just the geometry for the front UCA's & LCA's that is still eluding me. If you know ANYWHERE I can find that info, I'd appreciate it. I've scoured the internet & called a few automotive engineering friends of mine but nobody has it. The project is stuck until I figure out how to get those measurements unfortunately.


Quote:

Originally Posted by phantomjock (Post 134123)
And I have a pair of the C7 uprights that have been "molested"-- BUT IN A GOOD WAY. The upper ball joints have been pressed-out and a sleeve inserted. This lets you choose an extended ball joint to work camber change. The lowers have been reamed for 6141 ball joints - a more common BJ from circle track racing.
If you are planning on using the "stock" GM upper and lower control arms - forget about these.

But--if you are thinking of designing your own, they could be very useful. They still take the GM/SKF bearing. The C7 uprights are much lighter than the earlier C5/6 uprights, GM learned a lot about strength to weight and changed their castings. This image is not of mine - but representative. [Only registered and activated users can see links. Click Here To Register...]

I'm going to full race mode and my suspension is now all rod ends.

I would let these go for less than what they cost from GM Parts Direct (they had the best price) and no charge for the machining. In fact I'd make a deal for Black Friday too! (need to get them off my shelf!)

Sounds like a real cool project. Look forward to seeing the plan/layout and pictures of the build too!

Cheers - Jim


phantomjock 12-18-2020 11:30 AM

A couple of paths here and sound s like you have chosen (or are close to choosing one).
1. Use the Bearings + Uprights and build/mount your own Upper/Lower Control Arms.
2. Use the "stock" C5/6/7 upper and lower control arms and sort how to mount them.
3. Buy a full kit uprights to hubs and ready mount cross-member witrh shocks, ARB etc. ($$$).
I've personally opted for path 1, but that comes with its own set of consequences.

On path 2, there are a couple of guys here that are moving more or less that way. It comes with its own set of fabrication challenges and skills required too. [Chris and Pappy come immediately to mind]

I've not seen anyone here take option 3 - but I'll admit there are some advantages if starting from scratch.

To your question:
For the C5/6 layout, I recall Performance Trends has the points in their sample software you can get as a free trial. I don't recall if just the rear, or both. You'll have to some digging around - Its been a few years since I've used up my trial version.

For the PT trial, you can try it here: [Only registered and activated users can see links. Click Here To Register...]

Not specifically what you were asking for, but maybe encouraging. A fellow did a version on his 1929 Ford Roadster here: [Only registered and activated users can see links. Click Here To Register...]

A set of numbers that may require some checking are here: [Only registered and activated users can see links. Click Here To Register...]

And if you are into CAD, might try these too: [Only registered and activated users can see links. Click Here To Register...]

Also as a member check the download sections here too. There might be some data there

Best of luck - Post Pictures too!

Cheers - Jim

BBShark 12-18-2020 11:45 AM

C5 suspension points from download section:

[Only registered and activated users can see links. Click Here To Register...]

phantomjock 12-18-2020 02:46 PM

BBShark has a good link there too. I just found an XLS spreadsheet I'll load up too. Always surprised what I've saved over a bit of time!
Sorry its too big to load here and work a file xtn change, so will post in Download section.

Cheers - Jim

Boomstick33 12-19-2020 05:08 AM

Thanks, I actually downloaded that file when I joined the forum, saw its from the Performance Trends Suspension Analyzer, but I've never talked to anyone that's actually used their free canned tune in that program. Not saying I don't trust their measurements, but I was hoping to find someone that has used those measurements successfully before I take them as gospel and weld up the tube frame.

Anyone here use those successfully??

Quote:

Originally Posted by BBShark (Post 134256)
C5 suspension points from download section:

[Only registered and activated users can see links. Click Here To Register...]


Boomstick33 12-19-2020 05:26 AM

Awesome, I'll look for it in the downloads section when you get it loaded up! Thanks for the helpful info in the previous response too, I appreciate it!

As soon as I get this project closer to completion, I'll post pics. It's something new, a complete new design of an older design of a two-seat sports car. Everything was cruising along fine until Covid. My structural engineer that was assisting me is an older gentleman and decided to resign to his own house until everything gets better, and since I'm around Covid patients all the time, I can't fault him at all. It just leaves me in a complete lurch, I can fabricate...but that much engineering is where my skill set lacks lol.

Quote:

Originally Posted by phantomjock (Post 134257)
BBShark has a good link there too. I just found an XLS spreadsheet I'll load up too. Always surprised what I've saved over a bit of time!
Sorry its too big to load here and work a file xtn change, so will post in Download section.

Cheers - Jim



All times are GMT. The time now is 08:16 PM.

Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.