Suggestions on subframe connectors for 70 Challenger?

[crash340]

For Brad,
I like your method, if one wanted to spend some extra time do you think it would be an idea to run a brace on say a 45 deg at the front of each bar say out to the sill end of the torsion bar cross member and then so out riggers to the seat bolts just to try and give it that little bit more??
I like the idea of the US Tools pieces for ultimate rigidity but dont want to have such a permanant fit in case I want to revert the car back to factory original one day.

Greg

[brads70]

I don't see the need to do that but I guess you could? Not sure how strong your suggestion would be also? ( If I understand it correctly?)

[crash340]

Just trying to obtain some extra body bracing, tortional twist reduction etc

[dakota]

I ended up buying the US Car Tool subframe connectors.  The combination of a sale at US Car Tool, a desire to take advantage of the car interior already being out (don't want to have regrets later), and the position of these being mostly out of sight once installed were the main factors .  I have received lots of warnings from some local car guy about making sure the frame is appropriately supported and aligned before any welding starts, so there's a bit more research ahead to find someone to do the installation.  I don't trust my welding skills on something structural like this.   

[HP2]

 You would want to put it in the air with 6-8 jackstands holding it up. Verify level and plumb. I typically put one set right behind the core support, one set at the cowl, one set at the front leaf hangers and one set back on the leaf shackles. Maybe pull a few diagonal tape measurements to make sure everything is relatively square. If you really want to get into the details, you can use a plumb bob to drop reference points on to the floor and verify all you chassis dimension before you start. Once you're satisfied with the layout, install and start welding.

[jimynick]

If the car is original and hasn't been in an accident of any real intensity, remember that the car sits on it's tires/suspension. If the panels fit decently and the doors open and close similarly, then all you need to do is put the car on 6 ton stands (they're much higher than 2-3 tonners) under the diff and lwr cntrl arms, close the doors, check their fit and if it's all good, go to town. I've just finished tacking my US Car Tool ones in and while they do require some marking and grinding, they're not too hideous to put in and they fit up well under the car and make it much stiffer. Good luck 

[Topcat]

Leave the doors shut on at first if you haven't taken them off.
Set them on 6-8 jack stands as earlier said.
Trial fit U.S. Cartool connectors on and off until they're snug fit.
The holes pull the connectors in tight to the body with a bolt. Leave it on till done.
Tack weld them on 8-10 spots on each one, each side.
Put back on rotisserie since now the whole body has full center support.
Flip it, and finish up the welding.
Keep thought on how you position the E brake cable thru the frames.

[dakota]

Thanks for the advice and the great pics.   I add some updates once the subframe connectors go in... I'd guess a month or two from now.   

[jimynick]

boy, Mike! Your car must've been the pattern car for those connectors. Mine had spots that were 5/16- 3/8th apart. Your install looks good, but reminded me that I'll have a wee bit of fun when I go to put in the torque boxes. 

[Topcat]

Put your rear torque boxes on first before the connectors.

You can do the trail fitting without welding while the car in on the rotisserie sideways.
What I mean by that is: Do your contours/modifying of the frame connectors to body and trial fit them. 

Do that prior to setting car on all the jack stands.
Then weld them in after one final fitment double check when on stands.

[rhamson]

Even if you don't upgrade the horsepower I would highly recommend stiffening the body with a good systematic body strengthening kit. I used US Cartool which had some fitment adjustments but I feel has made the whole platform much more solid. It can only help a Hotchkiss suspension upgrade which I intend to do. My only dilemma with the Hotchkiss or the Alterkation upgrade is the look of the recommended 17" rims. It really takes away from the musclecar image IMHO. But I totally get the performance reasoning. The question is how much will I use that increased performance. It's not like I am going to go out and road race this car.

[HP2]

If you stay with the 12" brake rotors, you don't have to step up to 17" tires, but the choices of 17" tires is much larger than in the 15" range.  To get a decent look out of 17"s you will need to look at 40 or 45 aspect ratios, which may mean using truck tires.