67 Camaro build (C5 suspension and transaxle

[maro67]

Picking up where I left off. I had some time before I was able to get back to the car and did a lot of thinking and planning of the suspension. I had always wanted to run all C5 suspension. At some point I had settled on the C4 platform for several reasons. Well, I decided I would regret it if I didn't build this car the way that I had originally intended. Long story short I came across a really good deal on front and rear C5 suspension with brakes that I couldn't pass up.

I'll get to that but first order was to un-mount the front frame rails and drill out the mounting tabs for poly urethane mounting bushings. The frame rails came will slotted holes and solid mounts. I really wanted to go with poly mounts so I had to do some modifications. I took some pictures of the frame rails when I had them off the car to show you what they are like.

[maro67]

All in all, I am happy with the product as received, especially for the price. They will do what I want from them. Here are a few shots of the welds (mig) and the gussets on them mounting tab.

I didn't wind up getting any pics of the rails after I had drilled out the mounting tabs. I used a hole saw to drill through the 3/16" tabs. I made a drill guide out of a piece of aluminum plate that I had lying around so the hole saw wouldn't walk / wobble on me. When all was said and done it worked out well and I ended up with 29in between the inboard surfaces of the rails when mounted.

[maro67]

I re-mounted the frame rails with the poly bushings. Since the rails are loose at this point I cut some pieces of 2x4's to 29in (I used a hand saw and a sanding block to get them as close to 29" as I could) to use as spacers. I used some ratchet straps help hold everything in place. This helped to square everything up.

Okay on to the good stuff. Here are a couple pics of the initial mockup / layout of the C5 front suspension cradle and lower control arms.

[maro67]

I fabbed up a jig to help locate and level the suspension cradle. I used the bolt holes on the underside where the mono leaf spring would mount. I can adjust each of the 4 corners independently. The nice part is that I can make fine adjustments by turning the upper nut and then lock them in place with the lower nut. I am using a bubble level on top of the mounting tab on the cradle where it will bolt to the frame rails.

[maro67]

I mounted the front fender extensions, valance and header panel to make sure the front clip was all together. I wanted to do this before I centered the front suspension assembly. Over this weekend and next week I will be working on setting the stance and welding on tabs to mount the front suspension cradle.

[maro67]

The way it is working out I will have 5in of ground clearance to the bottom of the suspension cradle. The control arms are set level (0 deg from center of vehicle out to the wheel). This is the equivalent of a slightly lowered C5 so it very close to stock geometry. I am not going to change the width or narrow the suspension.

Right now I have the front of the car jacked up a few inches so that I have room to work and move everything around. It is looking like the wheels are going to stick out past the front fenders about 3/8" on either side. My plan is to flare the fenders to make everything fit. It shouldn't take too much to gain the extra clearance I need.

Here is a picture of what it looks like at the current moment.

I am mocking it up with 0 deg front camber as the stock C5 alignment specs do not run much neg front camber at all.

[maro67]

Made some more progress on the front suspension over the past week / weekend. I've been using a regular 4ft level across the frame rails to ensure the car and frame are level. I spent a good amount of time focusing on making sure the suspension cradle was level, centered and square. Like I mentioned in the last post, I used a bubble level on the mounting surfaces of the suspension cradle. It took several iterations of adjustments, but I was able to achieve a good balance across all 4 mounting pads.

The bubble isn't quite dead nuts centered, but I was at least able to get it "in the circle" on all 4 corners, the jig helped a ton. I checked level across the mounting points with the 4ft straight level and it all looks good.

Passenger side rear


Passenger side front

[maro67]

To get the proper ground clearance for the suspension and set the overall stance of the vehicle, I had to notch the frame rails for the front mounting pads on the suspension cradle. I wound up cutting a 1.5 notch from the bottom of the rails. I was hoping it wouldn't require that much material to be removed. But I've got a good idea on how I am going to reinforce everything.

Well, that's all I have time for now. Got to take advantage of a sunny morning and get out and ride the Buell! I'll post up some more pictures later.

[maro67]

Okay, where was I? Oh, Happy Easter everyone!

So as you can see I had to notch the frame rails to accommodate the front suspension cradle. I made a decision to use the suspension cradle vs. fabricating lower control arm mount, etc. There are pros and cons to going either way but I really want to be able to run as many oem components as possible. Keeping the cradle allows for things like stock steering rack, accessories, oil pan and more.

However it does come with its own challenges. For example, now that the frame rails are notched, I need to fabricate mounts. I am using 3/16" plate. You can see that the outboard wall of the frame rail interferes with the both the locating dowl pin and the mounting bolt hole. I wanted to keep the dowls so I decided to trim them flush with the mounting plate.

You can see what I mean a little better in this picture. The dowls were an easy fix. The mounting bolts were really close. I could insert them up from the underside of the cradle. Unfortunately the od of the bolt was basically flush against the outboard wall of the frame rail and would not allow room for either the head of the bolt or a nut and washer.

[maro67]

At this point I needed to come up with a way to address the mounting bolt interference. I believe I mentioned in an earlier post that I plan to install reinforcement down tubes from the firewall that will tie into the frame rails. I chose to take advantage of that and incorporate a solution for the mounting bolt interference and use it as a tie in point for the down tubes.

I cut another (vertical notch) in the frame rails. I am using 2" x 0.125" square tube mounted vertically to tie into the mounting plates and the frame rails. The mounting bolts can be dropped in from the top side of the square tube.

The vertical tubes are centered on the mounting bolt holes, so there is plenty of rim inside the tube for the head of the bolt and a washer as well as clearance for a socket on an extension. I cut these piece with excess at this point. I can trim them to whatever height they need to be later. I'd rather have extra material now and be able to cut to length later than the other way around. As of now my plan is to use the vertical tubes to tie into down tubes from the firewall as mentioned. However, if I dont like how that plays out and choose to go another way, I figure I can always trim them flush with the top of the frame rail and close it out with another piece of 3/16" plate with a hole cut for the mounting bolts.

Here are some more pictures showing how it all ties in together. In addition to acting as a solution for the mounting bolts, these tubes should add back some much needed strength to the frame rails from where they were originally notched for the suspension cradle. If I can tie them into firewall down tubes that will just stiffen up the whole structure that much further.

[maro67]

Next up is the rear mounting tabs for the front suspension cradle. Fortunately these are much more straight forward.


I am using 3/16" plate for the mounting tabs.


I am going to tack weld everything in place then move onto the upper control arm and shock mounts. My thought it I will weld everything that I can on the bench and then tack the brackets, etc. in place. I will then uninstall everything and finish weld everything with the frame rails off the car. This will make it much easier since I can avoid vertical and over head welding positions.

I have a few things on my to do list around the house this week. I am hoping to get back on the car this weekend.

[maro67]

Time for some long overdue updated. I just wrapped up the final welding on the front subframe and will be moving to the rear suspension. Time to tackle getting that C5 transaxle installed. But first some pics of the front subframe and suspension.

Since my last post, I decided to remake the back mounts for the suspension cradle to frame rails. I wasn't crazy about how the 1st ones turned out. This time I chose to make them from a single piece of square tube. You can also see how I chose to add 2in square tube for mounting the upper a-arms.




I fabricated what I will call upper frame rails out of 2in x .125 square tube. These are used to mount the upper control arms and upper shock mounts. They tie into the main frame rails firewall body mounting tabs and the vertical tubes.

[maro67]

I am keeping with the C5 stock suspension geometry, so I made the miter cuts to place the upper frame rail section that the control arms will mount to at the same angle as the oem mounting points. This will keep the anti-dive characteristics of the C5 corvette intact. Since I am going to be using the T56 transaxle, rear suspension and torque tube, along with an aluminum gen IV LS motor, this should work out well for a street car.

I a guesstimating the finished car to weigh in around 32xx lbs. Right in the ball park of a stock C5 corvette. I am going to run the C5 Z06 factory leaf springs and sway bars. Since the Camaro is about 3.5 inches longer than the Vette, I am going to attempt to keep the torque tube at the stock length and make custom motor mounts to setback the engine accordingly. Again, my guesstimating puts this setup close to the C5 stock weight distribution.

Given the way the factory front upper control arms mount, I am going to make the anti-dive angle fixed. I may make the rear suspension upper control arm mounting points adjustable, so as to be able to tune the anti-squat. I'll cross that bridge when I get there.

[maro67]

I added some gussets to the upper frame rails at the miter joint. Also, I drilled the holes and notched the rails to mount the upper a-arms. The notches will get boxed in to maintain strength of the upper rails.



Here you can see the reason for notching the upper rails. Also, I left a little bit of clearance to be able to shim the upper arms as needed for alignment. During the mock up I centered the lower arms mounts in the slots on the suspension cradle. This should allow for proper alignment once all is said and done.

[maro67]

I decided I needed to add some additional support / bracing before I fabbed the upper shock mounts. I cut some pieces from 3/16 plate added theses braces to give some more rigidity.



It's starting to take shape.

[maro67]

Next up was the upper shock mounts. Used some more 3/16in plate for these. I didnt go too crazy with the structure for the shock mounts, as I plan to run the C5 leaf springs. Even if I switch to an adjustable shock, the mounts will only have to carry the dampening loads. The leaf springs mount to the suspension cradle and which supports the sprung weight of the vehicle.

[maro67]

Well that is it on the front subframe fab for now. I plan on making a removable cross brace (maybe and "X" brace) that will go in between the vertical tubes. I also have some ideas on how to make a bolt in shock tower brace. I am going to wait until I get the engine set in place with the accessories mocked up before I go any further. I also make add an additional gusset between the main frame rails and the upper rails close to where they tie into the body mounting tabs. Again, I want to wait until I get a little further along to make sure there are no clearance issues with things like the steering shaft, etc.

It is finally time to break this down and do all the finish welding.



I'm certainly no pro but overall I am happy with how things are turning out. It's a lot of welds for my little Eastwood mig machine. I had tun into the duty cycle a couple times and had to let the machine take a rest but it got the job done.

[maro67]

After finishing the welding I hit everything with some of the Fast-etch to get rid of any rust and provide some corrosion protection. I plan to have these powder coated when all is said and done. Time to re-assemble the front end before moving to the back of the car. It wasn't too bad getting everything back in place. The dowel pints on the suspension cradle help getting everything aligned. I also left the suspensions cradle mounted to the frame table when I broke down the frame rails so really that made the job a hell of a lot easier. Other than that a couple ratchet straps and my calibrated 2 x 4 to set the distance between the rails and the body mounting points and shes good to go.



That all for now. Time to get that rear suspension cradle set in place and start laying out the rear frame rails. I have some basic ideas as how the overall design is going to be but I'm sure I'll have to make some changes on the fly.

[TANKMASTERJ]

That's a really nice. Project and some good looking Fab work Keep it up.
I didn't go that creative on mine but probably m sure impressed with yours.
I'm using speedtech front subframe and rear torque arm on mine but I did replace floor, trunk floor narrowed frame rails and mini tubs myself. I mocked up Al my suspension and ridetech stainless roll cage before I decided I need
Take it to a dedicated hotrod shop to get some metal replaced around my window areas and smooth my fire wall as I'm so busy with work.
I'm ready to get it back now and mock up engine tranny, heat and AC and my dry sump gear.
Jason's 67 Camaro is my build thread

[egoman]

Did you slug the upper control arm bolt holes? If not those will continuously loosen up with driving. Just trying to save you having to do this after powder coating.