FINALLY...A C5 to C6 diff conversion write-up.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
^^ Justin I appreciate your input - I'm having my shop check my plate to make sure it's holding up after a few months' use...if not we'll reinforce it!
Thanks for chiming in.
Thanks for chiming in.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Update = my shop checked my plate, it's 1/4" aluminum and is holding up great so far.
They played around with using a PFadt C5 rear mount on my C6...it looks like it would really spread the load on the cradle well, not just on the aluminum plate. It would need some machining to work as it's too tall but not impossible to do. We just didn't bother with it at this time.
Mike@hpsflorida took some pics, let me see if I can get him to post up.
Here's the Pfadt C5 mount.
http://www.pfadtracing.com/catalog/p...roducts_id/100
They played around with using a PFadt C5 rear mount on my C6...it looks like it would really spread the load on the cradle well, not just on the aluminum plate. It would need some machining to work as it's too tall but not impossible to do. We just didn't bother with it at this time.
Mike@hpsflorida took some pics, let me see if I can get him to post up.
Here's the Pfadt C5 mount.
http://www.pfadtracing.com/catalog/p...roducts_id/100
Last edited by Joe_G; Oct 31, 2009 at 09:52 AM.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Here are some pics of my cradle, my adaptor mount, and how a Pfadt mount looks. I think the Pfadt mount could pretty easily be nodded to work. If I was starting from scratch I think I would use it.
Thread Starter
Burning Brakes
Joined: Jun 2008
Posts: 1,214
Likes: 3
From: CA
Hey Joe,
Now that's something to think about there. When I was fabing the mount I came up with an idea of designing a mount like the PFADT C5 mount for my C5 to C6 conversion but didn't give it to much thought at the time. I just wanted to get my car done. I was going to use something similar and use simple bump stops on the ends.
I've been drawing up specs and scetches for the past week but probably won't start fabing till I start adding more power to the car. I think the current mount it fine for now. I just finished my buddys car with a slightly redesigned mount, just a little wider. He loves it. I should've taken pics.
Now that's something to think about there. When I was fabing the mount I came up with an idea of designing a mount like the PFADT C5 mount for my C5 to C6 conversion but didn't give it to much thought at the time. I just wanted to get my car done. I was going to use something similar and use simple bump stops on the ends.
I've been drawing up specs and scetches for the past week but probably won't start fabing till I start adding more power to the car. I think the current mount it fine for now. I just finished my buddys car with a slightly redesigned mount, just a little wider. He loves it. I should've taken pics.
Burning Brakes
Joined: Aug 2007
Posts: 950
Likes: 3
From: Chesapeake Virginia
Hey Joe,
Now that's something to think about there. When I was fabing the mount I came up with an idea of designing a mount like the PFADT C5 mount for my C5 to C6 conversion but didn't give it to much thought at the time. I just wanted to get my car done. I was going to use something similar and use simple bump stops on the ends.
I've been drawing up specs and scetches for the past week but probably won't start fabing till I start adding more power to the car. I think the current mount it fine for now. I just finished my buddys car with a slightly redesigned mount, just a little wider. He loves it. I should've taken pics.
Now that's something to think about there. When I was fabing the mount I came up with an idea of designing a mount like the PFADT C5 mount for my C5 to C6 conversion but didn't give it to much thought at the time. I just wanted to get my car done. I was going to use something similar and use simple bump stops on the ends.
I've been drawing up specs and scetches for the past week but probably won't start fabing till I start adding more power to the car. I think the current mount it fine for now. I just finished my buddys car with a slightly redesigned mount, just a little wider. He loves it. I should've taken pics.
Thread Starter
Burning Brakes
Joined: Jun 2008
Posts: 1,214
Likes: 3
From: CA
I have a design down on paper but I haven't gotten around to actually building it. For the past months I've been having issues with my clutch which involved me having to tear the whole drivetrain out 3 times. So I've been pretty busy.
I should have something for you guys to look at within a month or so...if the car holds together. LOL. Actually I'll be ordering gears within the next few wks so the diff will be out and that's when I'll get to work on the mount.
The most problematic part will be clearance between the bottom of the diff and the cradle. There isn't a lot of room down there so fitting a mount like the PFADT is going to be challenging...BUT NO IMPOSSIBLE.
So far the "prototype diff mount I have is holding up just fine but there's a lot of room for improvements. I'm also working on a "bolt-in" mount that will not require welding a plate to the cradle....for those that don't have that option.
I should have something for you guys to look at within a month or so...if the car holds together. LOL. Actually I'll be ordering gears within the next few wks so the diff will be out and that's when I'll get to work on the mount.
The most problematic part will be clearance between the bottom of the diff and the cradle. There isn't a lot of room down there so fitting a mount like the PFADT is going to be challenging...BUT NO IMPOSSIBLE.
So far the "prototype diff mount I have is holding up just fine but there's a lot of room for improvements. I'm also working on a "bolt-in" mount that will not require welding a plate to the cradle....for those that don't have that option.
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Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
My buddy is putting a Pfadt rear mount on his C5...here's a pic of the standard C5 rear mount compared to the Pfadt.
The c6 conversion mount is similar to the C5 mount, but is quite a bit shorter. Thus, (and I'm guessing here) to use the pfadt mount, you'd need to cut that center U-channel part down by around an inch, and perhaps trim about an inch off the rubber snubbers on the Pfadt.
If you think about it, the small c5 center mount, combined with the torque tube and the engine mounts (see the Pfadt engine mounts in the picture also) cause the drivetrain to be essentially a tripod. The Pfadt rear mount "gives it legs" and allows the twisting forces to be spread to the sides of the rear cradle. As we have to weld a plate to our cradle in the C6 to C5 rear conversion, this Pfadt mount would take the stress off that aluminum plate we welded in.
Anyone who's ever had the misfortune to use a tripod engine stand knows, a 4 legged stand is much better (and safer).
Sparo you ready to mod these up? Keep track of your adjustments, I would like to put one of these on my car.
The c6 conversion mount is similar to the C5 mount, but is quite a bit shorter. Thus, (and I'm guessing here) to use the pfadt mount, you'd need to cut that center U-channel part down by around an inch, and perhaps trim about an inch off the rubber snubbers on the Pfadt.
If you think about it, the small c5 center mount, combined with the torque tube and the engine mounts (see the Pfadt engine mounts in the picture also) cause the drivetrain to be essentially a tripod. The Pfadt rear mount "gives it legs" and allows the twisting forces to be spread to the sides of the rear cradle. As we have to weld a plate to our cradle in the C6 to C5 rear conversion, this Pfadt mount would take the stress off that aluminum plate we welded in.
Anyone who's ever had the misfortune to use a tripod engine stand knows, a 4 legged stand is much better (and safer).
Sparo you ready to mod these up? Keep track of your adjustments, I would like to put one of these on my car.
Melting Slicks
Joined: Feb 2003
Posts: 2,966
Likes: 22
From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11
The 05 C6 are the only year that the C5 diff will bolt to (05 essentially has a C5 MM6). I have used a 05 trans into a 2000 FRC without issues.
Burning Brakes
Joined: Mar 2007
Posts: 1,107
Likes: 9
From: Wichita Falls, TX
This is good information to know. At least they did something good for us 05 C6 owners. So I can use the 01-04 C5/Z06 Diff without any modification issues, is that correct? If that's the case, once I start modding heavy, I'll start planning to save for this purchase.
Pro
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From: North Port Florida
Team Owner
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From: Short Hills, NJ
Melting Slicks
Joined: Feb 2003
Posts: 2,966
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From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11
Drifting
Joined: Jun 2007
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Novel idea for sure!
But as a welder I want to say...your welds suffer from porosity which is caused by atmospheric contamination due to improper shielding gas. Porosity degrades the strength of the weld and can lead to failure.
But as a welder I want to say...your welds suffer from porosity which is caused by atmospheric contamination due to improper shielding gas. Porosity degrades the strength of the weld and can lead to failure.
