Why would replacing the spot welded flange with a solid weld retaining the factory radius bother anything? With a motor plate the front frame rails now have a tied member above and below the rail. The thinner cross section in the center (it is boxed) hasn't shown any point of failure over 750 passes of use.
Doug

Was the guys name Jim? Did it have a motor done by best racing engines. If so that is the car im thinking and it is a very nice car.. good luck with your project.

Here is other one

T/B don't mount to the K-member. they go on the lower control arm

Al,

I would caution you going with the QA1 tubular deal..

If you ever plan to run the car in NSS you have to keep the torsion bars and drag link. Hence, why the lightened stock K frame is typically the weapon choice for most. I run one similar to Doug.

Just my 2 cents.

Casey FJ

Yes it was Jim's car. Just got to the point for him that he couldn't enjoy the car anymore due to some health issues. He did a great job with it and we will just take over where he left off. I have already made some changes to the engine and the car itself but the bones were very good for sure. Our plan is to take it completely apart hopefully this winter and start the process of making her better, or better said giving her the love she deserves from an appearance standpoint. Still undecided if we will keep it the same color or not. If so the interior will be switched over to blue most likely as well and if nothing changes I will likely stick the Hemi I have in it. But I would rather sell the Hemi frankly and leave this alone other than freshening it up and making some more little changes.

Casey as for the k member deal I will likely just lighten up what's there as I have done in the past. never had an issue with them done that way ever and I have done 4 to date.

1. if success is justified by number of non failures, then the Challenger was pretty successful, until launch #25.

2. Not sure if we are addressing the same concern here, mine was about removing/narrowing OEM K member flanges, and then replacing it with any weld, The spot welds are not the main issue, and with millions on the road with just spot welds, they themselves have a pretty good track record. Removing/narrowing the flanges is IMO like removing the flanges on an I beam, one can do it, but if always reduces strength/stiffness, And the outermost edge of a flange can in some cases contribute the greatest stiffness, by weight to the structure, meaning its the last place to start trimming normally.