67 Camaro build (C5 suspension and transaxle

[maro67]

Time for some updates. Since my last post I have just about finished the mockup on the rear frame section. I had mentioned that I was fabricating removable rear shock mounts. I made them from 3/16 steel plate. They attach to the rear frame section with 2 bolts in the vertical position and 1 in the horizontal. In this picture I have only pilot holes drilled that I used to transfer / match drill the frame.

[maro67]

I dont really have any good pictures of the shock mounts bolted to the rear frame section. This first one is from when I was mocking things up and transfer drilling the pilot holes.


This one shows the finished shock mounts bolted to the rear frame section before I mounted the hole thing back under the car.

[maro67]

At this point, the center section of the rear frame is pretty much complete. I will have some mounting tabs for exhaust hangers and brake lines but that is further down the road. The next order of business was to get the frame centered back under the car so I could layout how it will mount to the body. I dont recall if I had mentioned previously, but I plan to bolt the rear frame to the body where the oem leaf springs mounted. I figured the body was originally designed to be supported by the leaf springs at these locations and they are reinforced. I can also tie the cage into the mounting points to further reinforce everything.

At the back of the car I am using the leaf spring mounts in the oem rear frame rails. I installed leaf spring poly bushings in the factory frame rails. I fabricated a cross member with mounting tabs out of 2 x 3 x .125" rectangle tube and 3/16" plate.


The whole thing will bolt to the rear frame rails the same way the leaf springs did. I left a little of clearance so that I can install a washer or two on either side to make sure everything is perfrectly centered once it gets permanently installed. Here is a close up on one of the ends.

[maro67]

I have been being very conservative with the amount of floor that I cut out of the trunk area. I want to retain as much of the oem sheet metal as feasible. One of the main reasons for this is that the trunk floor adds a lot of strength and rigidity to the rear of the body, especially in the area where the hump for the solid axle rear housing and the inner wheel tubs. This is probably about what I am going to be looking at to make room for the rear frame and differential. I will still have to cut more material out for the transmission and torque tube but I am trying to focus on one area at a time.

When all is said and done I am going to have to fabricate new sheet metal sections to close everything out. I picked up a bead roller so I can try to regain some of the strength lost when cutting out the factory trunk floor section.



This picture will give you an idea of how much room is needed to fit the C5 transaxle under the 1st gen Camaro body. As I have mentioned I've been trying to keep everything as compact as possible.

[maro67]

With the rear frame center section and suspension cradle located back under the car, I bolted in the rear cross member. It is a bit difficult to get good quality pictures from underneath the car but I will do my best. Once installed, the cross member tucks up under the rear of the car nicely. From the side view everything is hidden. From the rear of the car you can just barely see the tiniest bit of the cross member below the rear valence. I honestly think once the car is on the ground and everything is painted you wont even notice it. It basically sites where the rear of the oem gas tank would be.

[maro67]

I used two pieces of 2 x 3 x .125" with a miter cut to make rear rails to connect the frame center section to the rear cross member. Everything it just tacked in place now. Once I get the forward connections made on the rear frame the whole thing will come out from under the car one more time for finish welding. I will also add some fish plates and gussets in key locations.

[maro67]

To mount the forward rails on the rear frame section under the car I came up with a pretty slick solution. I have removed approximately the forward 2/3's of the factory sheet metal frame rails. Including the section of the factory frames where the leaf spring pockets bolted to. I am fabricating forward frame rails that basically be located in the same space the factory rails once occupied. I have seen other aftermarket chassis and rear suspension kits bolt onto the oem rails but those things are just so dam thin that I couldn't bring myself to do it.

I am going to jump ahead a bit and work backwards. First I fabricated some square boxes from 3/16" plate. They are about 4.25" square on all sides. The top surface of the box is closed and that plate has a hole in it for some universal poly body bushings / mounts. The bottom of the box is open to get the rest of the body mount hardware in place and run a bolt up through the whole thing. This picture shows the two boxes mounted to the underside of the car at the location described above. Right now there is just about 5" of ground clearance to the bottom of the boxes and I can probably cut them down about a .25" to gain a little more.

[maro67]

This is what the body mounts / bushings looks like before being installed. They are a universal set of poly bushings. It is basically the same configuration as is used to mount the front subframe to the body.

[maro67]

One of the reason I chose this for the mounting points is that the body is reinforced in these locations. To actually bolt everything in place I am using the same "floating nut" assembly that is used at the front of the car. The actual pieces I am using are replacement parts that are meant for where the front subframe bolts to the location under the front seats. I like this because it is threaded for the correct size bolt, allows for a good amount of adjustment for centering the frame under the car and I figure they work at the front of the car so why reinvent the wheel. I havent welded them in place yet. I am waiting until the frame section is finished and mocked up in place. I want to make sure I have good adjustment in all directions.

[maro67]

Sticking with the 2 x 3 x .125" rectangle tube I fabricated some short rails for the forward side of the rear frame section to tie it all together. On a side note, a while back I picked up an inexpensive horizontal band saw from the "budget big box store". It took a good amount of effort to get it adjusted and the blade running true. But all in all for under $300 bucks the thing does what it is meant to. It also can be configured as a vertical saw which is great for cutting brackets from plate. Man I wish I pulled the trigger on this sooner. This photo shows the miter cut for the frame rail pieces I made with the saw. It is soooooooo much better than working with an abrasive chop saw and an angle grinder!

[maro67]

Here's a picture of the forward rails welded up with the body mounts.

[maro67]

Finally this thing is coming together. Its all mocked up and the forward and aft rails are tacked in place.

[Motown 454]

Great update. You've got a lot made and bolted in, Nice work!

[H'sPerformance]

This is what the body mounts / bushings looks like before being installed. They are a universal set of poly bushings. It is basically the same configuration as is used to mount the front subframe to the body.

Thanks for the info, and great update! Can you share the P/N for these?

[maro67]

Thanks for the info, and great update! Can you share the P/N for these?

The universal body mounts are made by energy suspension, the p/n is 9.4101R. You can beat the price. If you looks around you can find a pair for just under $30.

[ICrombie]

Great work on building the frame to hold the cradle! I may have missed it earlier in the thread, but what do you plan on doing for the gas tank?

[maro67]

Great work on building the frame to hold the cradle! I may have missed it earlier in the thread, but what do you plan on doing for the gas tank?

Plan is to run a fuel cell in the trunk and the muffler will go under the trunk floor in the area that the stock gas tank was, similar to how it is on the C5 and C6 corvettes.

[maro67]

The project is still alive and kicking. Been busy with a lot of other things the past 18months. I have made more progress since the last posts. Unfortunately I lost a bunch of pictures when my last cell phone broke. Essentially I finished the rear subframe and got it installed under the car then started modifying the trunk floor and interior floor boards to make room for the drive line.

I'll post up some more pictures over the next couple of weeks as I get back into it. Here's what I have right now.

[maro67]

[maro67]

Also, I had to take a break from doing the metal fab and started building a LS stroker motor. I have a build thread for the motor over on LS1Tech. I should be wrapping up the final assembly on the motor over the next two weeks then will be getting back on the car. Can't wait to get this thing on the ground as a roller!

https://ls1tech.com/forums/generatio...l#post20496798