grandspt

Hi everybody,
I did several searches but they are all older.
My question is has anyone new been using the (Ve__2Ve__) Frame stiffeners?
I see the price on their website has dropped to $525. Is it a worthwhile investment to keep a C4 frame fairly solid. My 96 GS with Z51 since new has always been flexi with the roof off (stable with the roof on). But the roof panel on very rough roads clicks and pops. However on a smooth road it is fairly quiet and still handles and rides like it should.
I would not mind adding these frame stiffeners as they are bolt in (no drilling) but if they do not work I don't want to waste my money!
Any suggestions from owners of these units or even from mechanical engineers that have seen them?

Thanks

kmillar

I bought the frame stiffener from Vette2vette, I plan on testing it on my '90 convertible in the next month or so. I've got the hardtop option, which makes the car more rigid than my coupe.

I'm going to compare the changes against the factory X brace and hardtop attached/ not attached. I'll post the results when I get around to the project.

One thing that helped me pull the trigger on the unit was that Jason said he would refund my money if it didn't work.

Hope this helps in the short run

oldalaskaman

alot of the members who auto-x use a frame stiffener as do the convertable members, I believe their cars came stock with them, others will chime in with more info, and also post the link to the site you referenced. they do work, theres also a few targa truss threads

-=Jeff=-

if you search my user name, I have the original prototype from Jason on my 1990 ZR-1

been on since May of 2010

http://forums.corvetteforum.com/c4-t...s-stiffer.html

http://forums.corvetteforum.com/c4-g...me-braces.html

Joe C

my 96 w/ the top off, feels like the ultimate "flexible-flyer". not to bad with the top on, but as another poster said, i've got some very minor creaking and popping. my 85 was similar, but my 90 felt more solid without the top than the others - go figure. i purchased a convertible X-brace, and i had a local fab shop box the members for a little more added stiffness. as soon as i get off my dead ****, i'll install it on my 96. i will have to drill holes for rivnuts at the rear mounting points, but it doesn't look like any big deal. i do have some minor concern about loosing about 1 inch ground clearance, but it's something i'll just have to deal with...

grandspt

Hi Jeff,
I have a couple of questions for you if you don't mind me asking?
Do the frame stiffeners make a Big difference in the chassis flex?
And how do you adjust them? I am still unclear how and what it is actually doing when you adjust the heim rods.
Thanks!

Also Kmillar please post your findings and installation progress.
I am trying to keep my car for a while and figure that anything to stiffen up the frame is a good step. I like the fact that this product is a bolt in (no welding is a plus).

-=Jeff=-

No problem

Yes I feel they do and I noticed it the minute I left the shop when we installed them

you loosen the lock nuts and turn the bar one direction or the other, as it turns one way both Heim joints tighten in the bar, turnt he other way they loosen.

Basically one HEIM is Opposite thread. ther eis no real spec to how tight. I have adjusted mine twice. they seem to be working great and I tend to forget I have them, but they do make a difference

PLRX

Dont worry, it will only hit the long speed bumps. My 92 Vert was stock and it rarely hot anything.

96 lt-4

I have the R-D racing camber brace(slight improvement by itself)and cross-frame(big improvement everywhere).It corners flat and has sharp turn in.No flex or annoying cowl shake with the top out.
Sacrifices ground clearance but well worth it IMO.Driving it w/o the cross frame is night and day difference compared to with it.I enjoy sharp curves with it.

Not what you asked about but works for me.Even if you buy the cross frame only you may not need the camber brace.I have never tried it that way.

Joe B.

grandspt

Thanks for all of your opinions, it helped with my decision to purchase the frame stiffeners from Vette2Vette.

Joe C

not to get OT here, but don't verts sit a bit higher to compensate for the X-brace?

pologreen1

Could be true. Mine sits like a 4x4 compared to my old coupe and other.

Joe B.

I am interested to hear of the results of the install.
So far I have read only 2 reviews of those stiffeners.
No engineer, but I really don't see how they could do much good,
adding a rod to an already massive frame member.
Seem expensive for what's in the kit, also.

oldalaskaman

there is a search function on this site an plenty of reviews from folk on here that use a frame stiffener in one form or another, they seem to like them...alot, I dont have any, so I'm not chiming in

Joe B.

I have the cross frame and camber brace on my car. I also use the targa truss when the top is off. Very happy with them. Yes, I am aware of and have used the search function.

96 lt-4

Going over speed bumps(when I can't avoid them)is like entry/exit on any parking lot with a grade,slowly and from an angle if at all possible.
I have the cross frame and have lowere the car and I rarely have a problem so long as I don't do something stupid.
The BMAD(Big Mouth Air Dam) scrapes more than anything.

grandspt

I will post my results. I should receive them by the middle of next week according to Jason.
Hopefully I will get a chance to install them next weekend and go for a nice ride next Sunday!

grandspt

Jason told me that Gordon Killebrew (hope I spelled it correctly) designed these and that they are a very similar design to what some of the Corvette Challenge cars were using.
I have no way of knowing this it is just what Jason told me per phone conversation.
I would believe they must add something to the structure if the Challenge cars were using a similar design!

grandspt

I installed the C4 Frame Stiffeners yesterday afternoon. About a 1 hour- 1.5 hour job. Very easy to do, the hardest part was the adjustment!
The car overall feels tighter. The pops and creaks from the roof panel have absolutely disappeared (which is what I was looking for it to do).

I took measurements with the roof panel on/off. I measured before installation. It was done in 3 spots from the middle of windshield above rearview mirror straight back to the halo. And from the Stripes on passenger and drivers side back to halo. I measured about 28 3/4" with roof off on one side and 28 7/8" on the other side. The car front was on ramps and the rear was up on jackstands under rear shock mounts.
With the roof on in the middle was still 28 3/4". The instructions said to jack up a corner of the car and measure before the install and then measure after the install. I noticed very little difference jacked up!
But my doors always open/closed fine when jacked up.

My first ride was impressive with the roof on. As I said my creaks and pops went away!
My next test was with the roof panel off. Note: My car since new has really been bad with the roof panel off (I can count on one hand how many times I have driven my Vette in 15 years with the roof off, it is terrible) it still is poor but much better, the steering wheel still shakes with the windshield cowl. But the car does not feel out of control on bad roads anymore!
To sum it up I am happy with the purchase as my GrandSport feels MUCH better, it rides when the car was new even a little better! The Z-51 suspension is firm riding and now it seems more stable over bumps!

Install notes:
Drivers side rear frame stiffener bracket interferes slightly with the Emergency Brake cable.
I had to remove the small E-brake cable wire bracket (one screw removal), bend E-brake cable away from the frame stiffener bracket which installs over the lowerer dog bone bracket. You reuse the original 19mm bolt that holds the dog bone bracket. After tightening the 19mm bolt I was able to move the E-brake cable around the frame stiffener bracket. So the E-brake cable is now leaning on the frame stiffener bracket. I then reinstalled the wire bracket to retain the E-brake cable.
Also the paint or powder coating (seems like black paint to me but I was told by Jason it was powder coated) makes getting a 7/8" open end wrench on the front hex of the rod impossible to not chip the paint off!!
I will get some black touch up paint so the rod does not rust. For $542 shipped I would have appreciated no chipping ( I was extremely careful).
Oh well
Hope this write up helps someone thinking of purchasing the frame stiffeners