Rear chassis flex. What do you think?, Discovery prepping for Road America next week Options

[vintage914racer]

Paranoia has set in as I'm nut and bolting the 914 before Road America next week. I'm hoping I can some second opinions.

A little background. My 914 has been a track car for nearly the entirely of it's life. She's been used and abused, but generally has been a reliable steed. Over the years chassis reinforcement and modifications have been made. Notably, the RR (pass) rear suspension console was replaced after the original tore (which is seemingly pretty normal).

What I'm noticing. After getting my car up on stands and prepping/inspecting for the next event I noticed a small amount of tire wear on my inner driver's left fender. I initially attributed it to bumping up to wider tires last Fall (225 Hoosiers vs. 205 Kumhos), but started investigating further to make sure there wasn't something else upstream.

When I have the car on jack stands and put pressure on the LR wheel, there's what I consider quite a bit of flex at the outer A-arm mount and forward into the rear long. You can see it in the attached video. As a point of comparison, when I do the same on the RR/passenger rear wheel there is some flex, but not as much. It should be noted that I had the inner suspension console replaced on the passenger side a few years ago after the old one tore, so in theory it should be stronger. 

The LR doesn't show any signs of tearing. It's also reinforced with stress bars on the outside and inside. 

Left Rear Flex Video (the side I'm worried about): https://youtu.be/NZDbDg22dFI

https://www.youtube.com/watch?v=NZDbDg22dFI


Right Rear Flex Video (the "control" if you will): https://youtu.be/bQMBecKZ6Yc

https://www.youtube.com/watch?v=bQMBecKZ6Yc



My questions are as follows:

1) How much flex is normal? Is this outside what is normal?

2) My flex test doesn't necessarily translate to how torsion is applied to the chassis when the car is on the ground, so am I worrying about something that isn't relevant? Wouldn't the applicable stress while driving get suppressed in part by the rear shock?

3) Would you be concerned about running the car?

Mid-term I'm going to get the LR console replaced for peace of mind, get the reinforcements cleaned up and tidy. The question is, should I forego my race and get it repaired before running.

[vintage914racer]

A huge thank you to Rick (rick918-s) for coming down to the cities from Duluth today to assess and ultimately fix my flex issues. He’s a true asset to the 914 community. It took him just a few minutes to determine that the factory spot welds that connect the flange in the inner (engine compartment) flanges to the exterior sheet metal were compromised and not connecting the inside and outside.



Following an afternoon of drilling, temporarily fastening with self tapping screws and stitch welding the drivers and passenger sides were back in business. No more flexible flyer. Now I just need to get an alignment before leaving town on Wednesday.

Huge shoutout and thank you to Rick. He’s one of the hood ones!

[SirAndy]

Following an afternoon of drilling, temporarily fastening with self tapping screws and stitch welding the drivers and passenger sides were back in business. No more flexible flyer.

I wonder if you can do some creative cross bracing to prevent this from happening again?
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