CFR Firewall Shifter Bushing, Fasteners Options

[NARP74]

Isn't that new washer defeating the purpose of the CFR bushing? If it is just a little bigger than the rod, it will make contact before the CFR does. The CFR has some built in slop, although engineered slop and a low friction material that might wear a little over time and is not prone to corrosion.

[technicalninja]

Not a chance.

Look at his final pics

The washer he made ID is close to the outer CF metal piece.

The shaft is 3/16 smaller on both sides than the outer CF piece.

The nut plate washer has a slightly larger ID that the original pass-through hole as well.

The only "gotcha" here might be too much compression of the nylon/plastic parts.

This set up might be stout enough to crush CF's bushing set up.

[Shivers]

Thanks: so you reached back from inside the cabin to put the nuts on….hmmmm
Sounds doable

No he made a nut plate out of the washer by welding the nuts on to the washer. So just locate the washer in place, line up the nuts to the holes in the firewall and run in the machine screws.

[TargaToy]

The only "gotcha" here might be too much compression of the nylon/plastic parts.

This set up might be stout enough to crush CF's bushing set up.

I was careful to check for any pinching or distortion. There's no additional friction whatsoever in the moving parts. The ceramic "eye" can still be flipped 180° with ease (with the shaft removed of course).

[technicalninja]

The only "gotcha" here might be too much compression of the nylon/plastic parts.

This set up might be stout enough to crush CF's bushing set up.

I was careful to check for any pinching or distortion. There's no additional friction whatsoever in the moving parts. The ceramic "eye" can still be flipped 180° with ease (with the shaft removed of course).

(IMG:style_emoticons/default/first.gif) (IMG:style_emoticons/default/first.gif) (IMG:style_emoticons/default/first.gif)

Not only a kick ass solution...

The builder tested the design before installation and thought about possible issues...

You want a job?

Only thing I'd change is those bitchy weld on nuts.
Not only a PIA to weld but you also have to be pretty precise OR redrill CFs bushing kit.

I'm going to look for a "bushing" bout the size of that washer and merely drill and tap it.
Aluminum should work fine.

[iankarr]

Great idea. That plate is a really nice upgrade to an already amazing one.

I've experienced both issues @chrisfoley mentioned...the hole wandering a bit, and finding replacment rivets when needed. Would be awesome to use the plate instead.

[jim_hoyland]

How would the plate compare to using RivNuts ?

[technicalninja]

All other forms of attachment rely on the firewall retaining the fastener.

A bolt through plate, like TargaToy built does not. When you tighten his down it pinches a 360 degree circle around the hole.

Sooner or later the Rivnut insert will loosen in its mounting just like the rivets or sheet metal screws

Sometimes you end up with a Rivnut spinning in the surface it's mounted in and that can RUIN your day, especially if you can't get to the backside to grab the Rivnut.

The Rivnuts will also stand the bushing off of the firewall surface the thickness of the outer portion of the Rivnut. This is enough to make me use a tiny bit of RTV between the bushing and firewall if I was installing using Rivnuts.

The Rivnuts require a larger hole and the metal between the original hole and the Rivnut holes might get pretty thin.

I was planning on simple pop rivets for mine until I saw TargaToy's solution.

Now, this thing we're talking about is NOT all that critical in how it's mounted.
It sees no real side loading and the original pop rivet design is not only easy, but also sufficient for most installations.

Want to go "full monte"?

Stick studs into the plate...

Studs would make that more user friendly to install by one person and I'd choose "nylocks" for the nuts.

Those button headed Allens do look great however!

Thanks again to @TargaToy

Sometimes "seeing" a problem through the eyes of others HELPS bigtime!

[TargaToy]

Adding to everything @technicalninja said, I also discovered that the area surrounding the firewall hole is not flat—at least not on an early car. Rivnuts would not have worked due to the profile of the OE boot flange/base. You can see better in this pic here. This was an early attempt to pull the nut plate up against the back side of the firewall before I took just a bit more material out of the ID of the washer.



I really love the idea of a thicker “washer” drilled and tapped. And the stud idea would be killer too. I could easily create that with what I already have here.

I’m really enjoying reading the innovative ideas! (IMG:style_emoticons/default/beerchug.gif)

[nivekdodge]

Installed one today with the rivets and it went perfect

Kevin

[technicalninja]

Got me thinking...

That washer is ALMOST thick enough to hold threads as-is.

Here's a way to make it work.

New washer, drill and tap for 6X1. Need to be accurate, drill press and "technical vise" would help BIGTIME.

I'm betting you know this already.

Thread studs through washer and add nuts. Set stud installation depth and tighten nuts against washer. You just LOCKED the stud into the washer.
After checking alignment against the CF Bushing pack I'd loosen, add red Loctite, retighten.

That's a permanent solution in my book.

You can find 12 point 6X1 nuts to maintain style...

I just searched a bit and found Ti 12 points that would retain the coolness of the hardware.
https://www.amazon.com/Wanyifa-Titanium-12-...B0BDG7Y68P?th=1

External ONLY! The internal nuts should be cheapies...

I'd look at 5 X.8 versus 6mm stuff. I'd have to play around with it.
6 seems big to me for this application.

[HansJan]

For those that are on the fence.
This bushing really helps.
On my car I went for the CFR firewall bushing, linkage rod and modification at the gearbox. Total transformation, with very precise shifting.

[HansJan]

..

[VaccaRabite]

For those that are on the fence.
This bushing really helps.
On my car I went for the CFR firewall bushing, linkage rod and modification at the gearbox. Total transformation, with very precise shifting.

I did the same ages ago. Full kit and a Rennshift. Its a fantastic shifting 914.

Zach

[jim_hoyland]

And, the screws are fed from the inside of the firewall?

[NARP74]

And, the screws are fed from the inside of the firewall?

If they were studs, yes. The std install mounts the screws or rivets from the engine bay.

[jim_hoyland]

And, the screws are fed from the inside of the firewall?

If they were studs, yes. The std install mounts the screws or rivets from the engine bay.

So the nuts are put on from inside the cabin ; i’m not visualizing this.
And i want to know as i have a the CFR bushing ready for installation

[ChrisFoley]

M5 would make more sense than M6, which is oversize for the job. Even M5 requires the holes in my housing to be opened up a small amount.

[930cabman]

M5 would make more sense than M6, which is oversize for the job. Even M5 requires the holes in my housing to be opened up a small amount.

Chris,

thank you for allowing us nuts to keep our teeners in (better than) top shape

A big shout out to Tangerine (IMG:style_emoticons/default/beerchug.gif)

[GregAmy]

Installed one today with the rivets and it went perfect

Amen. Seems we've tilted off to the "let's be German engineers" wind side...

This is becoming more overly complicated than it needs to be. Pop rivets are working on my street car, rivets are working in my race car.

Rivets will work in your car too, bruder.