v2racing

There are multiple threads running on the Green Mamba build with video already, but what I noticed was the extreme frame flex at 7.38 on the video.

Look at the door gap and the back of the body bobbing up and down. Never seen another car flex like this, meaning other than Corvette.

I'm surprised he didn't put a roll cage in the car since he races it, it would have fixed this problem by stiffening up the whole frame.

Mike

drwet

Wow. That's an eye opener!

BackInTheGame

Makes me feel better about my SRIII frame under my 73.

2airtime2

I wish I had not been ignorant to the vette frame flex. I was adjusting my door gaps with car sitting on 4 jack stands supporting the frame. I now know the car needs to be sitting on the suspension for such adjustments.

Oh well, live and learn.

ajrothm

Yeah these frames are like spaghetti...

I had to spread my front rails just because they sagged together from years of use and high miles. (that's why they make spreader bars)

mrvette

I got lucky in that the P/Os of the old show car that is my '72 hotrod vette, had the frame welded up good in all the seams, and then my adding the cross support seems to be a NICE addition that I did about a dozen years ago.....

they did nice body/glass work back then, hard as hell to find anyone near that good with fiberglass today.....without spending 50 billion bux......

v2racing

The SRIII frame does look like it would be stiffer, but I'd like to see testing. I don't know if there has been any done.

Mike

Neil B

That video really makes me want to add a door bar to tie the rear cage to the frame rails near the a-pillar on my car.

JLmiller

Me too it took me 2 months and a lot of hours to figure this one out.

Amelio

Holy Hell!!!!!!!!!! I had no idea it was that bad!!!!

TCracingCA

I don't get not caging the car either! And even though I usually like the unusual, I hope this one isn't or doesn't get featured anywhere in a magazine!

metal tech

and in recent years there are some very high performing and $$ suspension systems been brought to market for this exact chassis. Haven't heard of any mentioning upgrades for the chassis to minimize the flex, hmmm. I thought that in the Herb Adams suspension book he had a method of measuring twist in a chassis that could be done at home. Not as accurate as what the big 3 use but it would give you some idea.

lionelhutz

It looks like a tire or driveline shudder started, which is fairly violent. So, no surprise it shook the body like that. If he does it enough times he'll break something in the drivetrain.

69autoXr

Or a Petty Bar. The roll bar in my car made a huge difference in (perceived) frame stiffness.

Jason Staley

My 4 pt roll bar made a decent improvement, but I'm considering a removable petty bar too. I'm betting it would make a noticeable improve.

redvetracr

more of a joke.

SB64

Love the mods, like the headlights, the bumper, the lower portion of the front end as well as the grill area. Lends to a bunch of ideas for the blue 69 project. AWESOME!!!
RVZIO

Milan454

Cool car but I would have edited that part of the video out. It adds nothing of any value. The down side is obvious. I would figure out how to brace the harness bar that's in the car now given that he states he tracks the car often. The flexing would probably be there on a Chevelle also only you would never see it. Wheel hop generates TREMENDOUS forces as we all know...

ignatz

I usually autoX with my tops on. Of course I have no idea what added stiffness there is, but there must be some!

v2racing

The Green Mamba and your car are coupes. The body in the video shows how little rigidity the body adds on the C3. Imagine how little the body helps with a convertible like I have.

I'm doing what I can to stiffen it up.

Mike