I tried those plugs about 20 years ago when Moroso started selling them and almost burned my car to the ground. I set the float level and left the plugs in the carb and did a quick trip around the block. Had a bad stumble going around a corner so I pulled over and lifted the hood. One of the plugs had melted or dissolved and fuel had spilled out of the bowl while going around the corner. Just had a little flash fire but it didn't get back into the carb. I walked home and got the brass plugs and that was the end of that.

i had a set melt/dissolve too, i left them in for a week or two before i noticed them, i was running a partial mix of race fuel and just figured that was the culprit, luckily it was caught before a large fire!

I've seen those.I thought about what would happen if one failed on a blowthrough set up. Instant 20+ p.s.i. fuel gusher spraying at a red hot exhaust manifold.NO THANKS.

I had a set on my carb for 8 years and my dad still has a set in his six pack that is over ten years old with no problems. If you try remove them they will most likely break off, as mine did. I just run them for setting floats now and put the brass plugs in after that, due to the possible problems. The new ones might not be as good quality as the older ones.

plastic expands more than metal do not over tighten,make sure orings are soft.

OR put them in the trash.Maybe you can make a tq wrench for them.j/k

they sure didn't like E85 either

Another heads-up on this subject, We dodged a engine fire by the skin of our teeth yesterday.

Took off the air cleaner housing on our six pack and noticed I had forgotten about the broken plastic fuel level window on the rear carb
after a dyno session.

Took the carb off, removed the bowl to drill out the remainder
of the sight glass...well, when I touched the plastic with the drill bit, it went through it like a piece of plastic wrap!!

We weren't far from a fire happening. found a piece if the plastic in the bottom of the bowl that had the consistency of chewing gum.

These were the Holley parts, so BEWARE!!!

Joe

Other than a nostalgia look, it makes no sense NOT to use the modern dual sight glass bowls or maybe modify stock ones and make your own. They have saved my azz a few times over the years like when you're warming up your car and all looks/sounds good but you see the glass solid w/fuel. The N&S had a piece of rubber fuel line stuck in it which hung it open and I caught it luckily.................

Which ones?

https://www.quickfueltechnology.com/carb-components/fuel-bowl-components/fuel-bowl-kits-1.html

Out of those 34-100 but I buy bare from BLP and add umbrellas and floats etc............