Mk III Roll Hoop Install

[Sdb999]

Car came to me fully assembled and running with roll hoop (driver's side) included but not installed. Fastener holes were not drilled prior to body install but I can work around that. Builder apparently shortened the hoop for personal preference, which is fine, it is still well above my head. The diagonal was shortened also and a slight jog was added. Fully assembled the hoop is 3/4" from bottoming on the mounting stubs on the frame, but still provides 2-1/4" of engagement there. I'd like to know how tall the hoop was originally, does anyone have that number? Standing upright on the bench mine is 23-5/16" tall. Any help greatly appreciated.
Thanks, S.

[Jeff Kleiner]

Top of the bar is 40” above the cockpit floor.

Jeff

[Sdb999]

Looks like 1" was cut off the hoop. That is countered by it's inability to bottom out on the frame mounts, which leaves me with:

Installed height from cockpit floor: 39-3/4"
Main hoop engagement at mount: 2-1/4"
Diagonal engagement at mount: 7/8"

I'll find some tubing to increase diagonal engagement to 2-3", then should be good to go.
Thanks Jeff.

[Sdb999]

One last detail. FFR assembly instructions show only (3) fasteners, one for each frame pickup location. So there is no fastener at the diagonal/hoop joint?
Thanks, S.

[michael everson]

It’s up to you if you want to put one in up there. I personally don’t
Like the look.
Mike

[ydousurf]

S, checkout this TFFF supported vendor for the "bolt-less" option to avoid the franken-bolt scenario, if that is what you are referring? And I agree with Mike too! This option might not be the strongest way to attach the diagonal down tube to the hoop, but it's better than nothing? I always say or think... If you flip it on it's top, you got other issues to consider anyway. So, keep the wheels on the ground and enjoy your ride!
https://520speedworks.com/

Doug

[i.e.427]

Fully assembled the hoop is 3/4" from bottoming on the mounting stubs on the frame, but still provides 2-1/4" of engagement there. I'd like to know how tall the hoop was originally, does anyone have that number? Standing upright on the bench mine is 23-5/16" tall. Any help greatly appreciated.
Thanks, S.

-There are welded spot welds used as stops that keep the roll bar from sitting flat against the chassis. It's supposed to be that way,

-A stock Factory 5 roll bar measures 24" from the bottom of the legs to the top of the roll bar arch but can vary up to about a half of an inch.

-The 7/8" stub that the third leg of the roll bar attaches to is more than adequate to bolt the rear leg and the main roll bar together, no need to extend it 2-3 inches.


I'd really like to see a picture of the "jog" that was "added".

[Sdb999]

Yep, just under an 1" removed from my hoop. When pushed down to the stops it is too low for the diagonal to fit as is. I'm thinking the "jog" was some attempt to compensate for the shorter hoop or adjust for manufacturing tolerances, either way it's very slight, only a saw kerf to get a slight bend. It fits the hoop very well with no gaps at the seam, I welded up the saw kerf and it's all good. The power coat was damaged from storage/transport so I'll have the assembly re-coated after final fitting. Pic attached. @i.e.427 174108
S.