C3/4/5 frankenstein frame

[vette427sbc]

Looks good, the C4 rear swap is probably the most cost effective rear upgrade for a C3. How much did you remove from the 1/2 shafts?

Thanks!
The shafts are 16.5" center to center. I think the stock ones are 18.xx?

 

[Bfit]

Stock lenth. Early c4 18. 1/8"
Bfit

 

[vette427sbc]

Finally some progress worth posting pictures of! But with Photobucket gone, what's the easiest way to post pictures that are on my phone? Posting from my phone is a bit cumbersome

 

[vette427sbc]

More

 

[vette427sbc]

I have a few more pics but they are too large to upload?
Anyway, heres the new plan of action...
Finish the rear suspension, rear frame rails will be clearanced for wider (much, much wider :smash: ) by removing the double walled section near the trailing arm pocket and narrowing it slightly. A new rear crossmember (where the diff pinion mount is) will be fabricated to be able to mount a sway bar to and to get rid of the bottomside bump out. The trans crossmember will still retain the box structure for rigidity but will be flushed to the bottom of the side rails. with both of those crossmembers modified, a *mostly* smooth underside (besides the trans case and oil pan) can be achieved.

The front of the frame will be cut off (C5 arms/spindles for sale!) with a front clip design from Ron Sutton Race Technology. Should allow for a 335/30/18 up front with 25-30* of turning under stock fenders. The clip is scheduled for delivery soon; pics to follow!

 

[SuperBuickGuy]

I figure you've got about a year before I need to copy what you're doing now hurry up? :smash::lol:

 

[phantomjock]

I have a few more pics but they are too large to upload? RESIZE MAN! Irfanview - freeby Gimp or??

The clip is scheduled for delivery soon; pics to follow! YES Bring on the Pics!

Thirsty for pics 1

Thanks mate for the update!

Cheers - Jim

 

[BBShark]

Really nice frame jig! Yes, more pix.

 

[rtj]

Vettemod will host your images, if you shrink them under the limit. But, the dropdown only works for me on the iPhone, so it is kind of a hassle.

 

[rtj]

I like your jig, just perfect for a full tube frame.

 

[vette427sbc]

Thanks guys! feels good to be seeing progress... The chassis work seen in the pics is actually being done by a friend of mine. He is doing the major metal work and Im going to do final detail/assembly. The roll cage will be reworked with some low profile door bars and four more forward pickup points. Ive also got plans to incorporate a rear motor plate of sorts to aid in torsional resistance.
:smash:

 

[vette427sbc]

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[vette427sbc]

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[vette427sbc]

I got nervous that VM wasnt coming back! Anyway... Heres some updates
Front suspension is mocked up and the frame section is welded in. The motor mounts have been clearanced for the front steer rack hand hopefully the use of only 2 u-joints.

 

[vette427sbc]

...

 

[vette427sbc]

Seems like some of my pics arent uploading from my phone... The frame is scheduled for delivery back to my shop this weekend where Ill be able to get some more pics to upload.
The pinion mount on the diff is adjustable for +/- 1.5* :3rd:

 

[Red77]

That's some impressive work!

 

[bobs77vet]

that pinion mount is impressive just by itself

 

[vette427sbc]

I wish I could take credit for the chassis fab! Thank you though Im super happy with everything
Frame was delivered back to my shop saturday afternoon... I spent a few hours just looking at it today. (for some reason my pictures are all grainy, Ill have to look into why) The first picture shows the bit of extra clearance gained with the straight frame rails. That is my old 285 tire that sat just inside the stock fender. It used to rub the frame under compression.

The rear swaybar is potentially temporary, I think its going to be a bit big but I just wanted to have the mounts and links made so when/if I need to change it I wont have to fabricate or modify anything once the frame is painted

The front clip step-down was removed because I didnt think it would fit the rocker channel firewall or my sidepipes. I think the merge plates came out great, and my sidepipes still fit!

My ABS pump is on its way so brake and fuel line pluming will begin shortly

 

[BBShark]

Your picture of the rear tire/frame rail looks like mine. I also have a 285 tire. Don't have the body on yet so not sure if I will have problems with clearance (tire to fender). My outside of tire to outside of tire width is 68 1/8". I measured the rear fender to fender max at 68 5/8". So, I'm only inside the fenders by 1/4".

I measured a stock 71 with 225's and got an overall tire to tire width of 69 1/4" so I think I'm good. I hope I'm good. Too late to change now!

 

[SuperBuickGuy]

wow - awesome

 

[vette427sbc]

Got my ABS pump in today so I can start wrapping up the brake lines... excuse the temporary ziptie mount! The pump is from a 2006 BMW M3. (Teves MK60) Its a pretty widely used pump in motorsports with a few options to upgrade for programmable and tuneable track oriented ABS. Capable of running standalone, so no need for the original cars computer. Wheel speed sensors, front and rear master cylinder port pressure sensors, and a yaw sensor are all the additional parts required

Let me know if pics are showing up? they are attachments from another forum

Your picture of the rear tire/frame rail looks like mine. I also have a 285 tire. Don't have the body on yet so not sure if I will have problems with clearance (tire to fender). My outside of tire to outside of tire width is 68 1/8". I measured the rear fender to fender max at 68 5/8". So, I'm only inside the fenders by 1/4".

I measured a stock 71 with 225's and got an overall tire to tire width of 69 1/4" so I think I'm good. I hope I'm good. Too late to change now!

Ill have to measure mine tomorrow to see where mine lay... Lots of mods without the body nearby for measurement! Fingers crossed!

wow - awesome

Thanks :2nd:

 

[bobs77vet]

pictures showed up nicely, that looks great.....even with a zip tie!

 

[vette427sbc]

Stoptech ST40 caliper bracket mocked up... had my neighbor (who happens to have a very cool C3 as well) 3D print the bracket prior to having it done on the CNC. Glad I did because a few measurements I had taken were off. This bracket is designed for a '88.5+ C4 with a C5 front rotor, a Stoptech ST40 caliper and an IPSCO mechanical spot caliper.

(apologies for the poor pictures... Im limited to the front facing camera on my phone so Im taking a "selfie" of these parts while trying to stay out of view :lol: )

 

[vette427sbc]

and now for some photos that are slightly less horrible quality :tomato:











So now on to the fuel lines... since my body is off the frame Im having a bit of a hard time knowing what is going to fit (or not!) around frame sections. Im running 2 -8 hardlines (aluminum, because theres a few less ounces :bounce: ) If anyone has any photos of the underside of their car, specifically how low the floors are compared to the frame rails and the gap between the body and front side of the frame crossmember where the frame rails kick up (I think the pre ~'75 cars were all the same floors?) I would appreciate it!

 

[bobs77vet]

that 3d printing is pretty amazing.

 

[BBShark]

So now on to the fuel lines... since my body is off the frame Im having a bit of a hard time knowing what is going to fit (or not!) around frame sections. Im running 2 -8 hardlines (aluminum, because theres a few less ounces :bounce: ) If anyone has any photos of the underside of their car, specifically how low the floors are compared to the frame rails and the gap between the body and front side of the frame crossmember where the frame rails kick up (I think the pre ~'75 cars were all the same floors?) I would appreciate it!

You have the same dilemma as me. I wish I would have paid more attention when the car was together. I'm pretty sure I will have to raise the transmission tunnel. As far as the lines, I think you are OK as long as they are in the same location as stock.

I'm trying to figure out how much room is between the back of the heads and the firewall because I'm running my fuel lines there.

What are you going to do with your frame jig?

 

[vette427sbc]

that 3d printing is pretty amazing.

Its great... I think I may end up getting my own printer; Its a very helpful tool!

(The centerbores are backwards in version 1) :withstupid:

You have the same dilemma as me. I wish I would have paid more attention when the car was together. I'm pretty sure I will have to raise the transmission tunnel. As far as the lines, I think you are OK as long as they are in the same location as stock.

I'm trying to figure out how much room is between the back of the heads and the firewall because I'm running my fuel lines there.

What are you going to do with your frame jig?

Im worried that the frame rails are off enough from stock to still fit the body, but wont support another ~.625 worth of fuel line. Plus, Im trying to make as much of the car serviceable without removing the body again. The fuel lines didnt fall into that category on a stock 69' :crylol: The jig is going to stay at the fab shop for now... Not sure what to do with it

Whats too big for your trans tunnel?

 

[BBShark]

You have the same dilemma as me. I wish I would have paid more attention when the car was together. I'm pretty sure I will have to raise the transmission tunnel. As far as the lines, I think you are OK as long as they are in the same location as stock.

I'm trying to figure out how much room is between the back of the heads and the firewall because I'm running my fuel lines there.

What are you going to do with your frame jig?

Im worried that the frame rails are off enough from stock to still fit the body, but wont support another ~.625 worth of fuel line. Plus, Im trying to make as much of the car serviceable without removing the body again. The fuel lines didnt fall into that category on a stock 69' :crylol: The jig is going to stay at the fab shop for now... Not sure what to do with it

Whats too big for your trans tunnel?

The transmission is a TKO500 but I set up my driveline angles to match. Problem is, I could only get the diff down about 1 1/2 degrees (stock is 0 degrees). The engine is down at the tail 3 1/2 degrees so that means the driveshaft is higher at the tailshaft. So, the transmission is higher than stock.

I probably should have set it up like stock. I'm just making things more difficult.

 

[SuperBuickGuy]

In the offroad world, we run 2* offset with no problem at all. The perfect world is 1* postive/1* negative front/rear but 2* - as long as the shaft is balanced - is fine. Maybe this can be your excuse to get a carbon fiber shaft?

and just for the record.... my FJ40 has 18* on the output and zero on the differential (cv joint in front)....