When replacing all my original vacuums, 2 lines goes through the firewall using an "all-in-one" firewall grommet/vacuum lines. 

I am not able to find a firewall grommet this size.  The hole itself is almost 1 3/4".  Everything they sell is the standard 3 or 4 holes firewall grommet; but they are too small. The biggest one, "outside diameter" is exactly the size of the whole in the firewall; it goest through by barely rubbing the sides.  I think this one is 1 1/2" or 1 3/8".  I need bigger!  Texas size!

I was thinking of reusing the original one; from which I have cut the vacuum lines from, but instead of simply using plastic fittings on each side; I tried to remove the left over inside tube; which has proven to be a disaster now...  Probably not much to do with that grommet anymore.  I have rendered it useless.

Where can I find a 2, 3 or 4 hole firewall grommet of this size?  I think I saw one for the C2 that could fit.  Can anyone confirm this or point me out to the right direction?

It's a 74 with A/C.

Thanks!

Steph.

Prolly no good to you now, but to get the remnants of the hose(s) out of the grommets, use a drill, and drill them out.

You might check with Larry at Corvette Specialties, or Paragon Corvette....if they don't have new ones, they will prolly have good used ones....

And...both of those places are reasonably close to you up yonder in Canadia.....


|UPDATED|9/12/2011 10:21:34 AM (AZT)|/UPDATED|

Actually; that's how I rendered them "almost" useless; by trying to drill them out.  The thing is the rubber is so flexible; it extends instead of getting removed by the drill.  The result is really not smooth inside and not much material is teken out.  I was thinking of freezing the grommet and try to drill it again to see of the drill is more effective this way.

Thanks for the referrals; I'll check with them.

Steph.

Rik's has them.

|UPDATED|9/13/2011 4:44:42 PM (AZT)|/UPDATED|

Looks like Bairs might have what your after as well...

Eureka!  I've put the grommet in the freezer overnight and correctly drilled it in the morning.  Problem solved!

Thanks for the reply's; I looked at both Bairs & Riks but both only had the "regular size" 3 or 4 holes grommet; which are smaller than the one I just fixed.   The only one I found online (and I must have looked at over 25 vendors...) was from Dr. Rebuild; he has one just like mine; where they have cut the lines flush.  Just need to connect the vacuum lines with a plastic fitting...

And you really have to wonder why they had a hole/grommet this big for only 2 (sometimes 3) vacuum lines....

Steph.

You can rest assured that the grommets were not just Corvette specific. I'm certain they were used across the GM line, with different layouts, as far as how many holes, and what size those holes were for the vacuum lines. Some engineer somewhere spec-ed out the requirements, and another engineer determined that they had one that would work, so that's what they used.

Glad you got it handled, anyway.