Ok what I ended up doing is I cut a new hose and ran from the bottom of the reservoir to the radiator filler neck. Then I was thinking I'd get another can for the overflow. But then I had an idea. I have a couple of the reservoir caps, maybe if I just drilled a tiny hole in the cap for venting?

So I tried it and drove yesterday to the Long Beach hot rod swapmeet and car show.  About 30 min in each direction. Warm day. Mix of stop and go and freeway driving. Performed perfectly. I think my problem is solved.

The catch can hose also has to draw from the bottom of the can back to the rad.    Not just catch the overflow

Interesting, so I should reroute the hose to the radiator so it's coming off the bottom of the can AND keep a vent hose on it as well? I only plugged it as it was leaking a couple oz's of fluid after a drive.

Hmmmm haven't see this one before. I recently changed over my radiator reservoir to a new one on my 66 Fairlane (see photo)....I had a vent hose on it but it was expelling a little fluid after a drive so I plugged it up making it a closed system. I popped the hood open the other day....3 days after driving it and this is what greeted me. (see photo)

No cooling issues when driving what so ever. And of course, as expected when I crack the reservoir cap it regains its shape.

What do you guys think?

Something is creating a vacuum but dammed if I can't figure out the solution.

On my 66 Fairlane, I'm seriously considering upgrading the Edlebrock heads and cam to TFS and a custom grind. The thought of going from 500 hp to 600+ is VERY appealing. I would consider doing it myself but I already work 10 hour days and my list is way too long. It'd end up taking forever. Gonna hit up my local classic Ford performance shop

My question is for those who know, how many billable hours should I be expecting to be quoted?

My shock towers have been shaved about an inch so that's helpful.

He appears to be. I see him post regularly about engines he's put together.

On my 66 Fairlane,

482 / Ebrock heads / TW / Holley 600's no choke / TKX / 500 hp.

1 pump and hold it to the floor and it fires instantly. It will idle at about 500 / die for the first 10 - 20 seconds so I feather it at 1000-1200 rpm. Then it's enough to back it out of the garage and down the driveway (idling at about 700) and start driving carefully down the street. But usually I just feather it until the temp starts coming up. 2-3 mins aand just go. I don't get my normal 900 rpm idle until it's pretty much up to temp. (180)

Today I fired it up and immediately starting driving after sitting for 3 hours. No muss no fuss.

Good idea, I did just that on Sunday and yep, it's all in the rear. Funny how it can sound like its up in the trans. Maybe the sounds was traveling up the driveshaft or something. I don't know but I'm happy it isn't the TKX.

Thanks!

Ok should be good now.