head o-rings for big bore

[JoeHazzard]

I have the Athena 392 big bore kit on my banshee and had a leaking o-ring that had a small chunk takin out of it. So I need some replacements. The cyclinders are 68mm and the o-ring looks to be about 75mm. Do most of the cool heads take this size o-ring. I'm having a hard time finding any Athena replacements and possibly some made from viton. Can anyone help I have a trip to motocove soon and need this thing ready.

[AKheathen]

I have the Athena 392 big bore kit on my banshee and had a leaking o-ring that had a small chunk takin out of it. So I need some replacements. The cyclinders are 68mm and the o-ring looks to be about 75mm. Do most of the cool heads take this size o-ring. I'm having a hard time finding any Athena replacements and possibly some made from viton. Can anyone help I have a trip to motocove soon and need this thing ready.

i wanna say the o-rings are interchangeable, as i've heard, but i have also heard you must have the higher heat range ones in there. i don't have a bb dome layin around anymore, so i can't check. i would check the site sponsors, like jeff, alfie, or wildcard, which will most likely be able to get them to you lickity split. worst case scenario, you can probably match them up at a bigger auto parts store or cat shop. you want the brown or orange ones(they are color coded for heat range and chemical/solevent resistance, etc) black is the bottom of the barrel rubber.

[JoeHazzard]

Well I found a place that sold the Athena 392 top end gasket set, so I went ahead and ordered it. That way I know they will be the right size, but their still going to be the lower quality black ones. So if anyone could measure stock size domes for me that would be great. Does anyone know what size domes the Athena kit comes with? All it said was that it would have 11.9 to 1 compression ratio and to use at least 96 octane. I haven't done a compression test yet but I would like to able to run straight 93. It would be a little easier on the wallet.