Progress Thread Snow - 93 GT Vert. Prepping for sale

Final pics
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If you are not seeing it running down the valve stems or it wet around the spring seats then it’s just evaporating.
Wouldnt that be a lot of evaporation? Even for 1hr?

Most folks use water instead of gas. Should I try that method also as to discount the evap? Some folks pout from the side ports and from the side and measure the leak into the combustion chamber. It seems like the casting of the head would make that challenging though.
 
Current thought is a complete valve job on the GT40 heads. I will upgrade the valve springs as noted below. I will use other stock parts, though validate proper push rod length.

Reason being, Im trying to save at least some money on the stock rockers. What I really want to get out of this effort is knowing I did my first valve job correctly. I can run this for a while and then re-consider cam, lifters, rockers, injectors, etc.

I should also add I have one more machine shop to check out this week. Assuming labor prices out in MA here are prohibitive for these cast iron heads, ill look to get the tools as noted below and start having some fun learning how to do proper valve jobs. Maybe recondition these beautiful and old cast iron heads.

Trick Flow® Valve Spring Upgrade Kits TFS-2500100: https://www.summitracing.com/parts/TFS-2500100

Ill need to pick up:
  • ProForm heavy-duty compressor
  • Proform Valve Check Springs 66793
  • OEMTOOLS Large Valve Lapper Tool
  • Permatex Valve Grinding Compound
  • Permatex Prussian Blue
  • Proform Valve Seal Installation Tools 67444
  • COMP Cams Magnum Checking Pushrods 7901-1
  • Which ?? Valve Spring Height Micrometer ??
Thanks again Dad for "getting a deal" on something which will end up costing me more time and money than you spent ... by like 5x!!
 
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Doing a different version of the hydro test.

First is exhaust valve. Did pretty good, but when I put about 90ish psi of compressed air against seat bubbles started coming up. Note one of the exhaust ports has another exit. I didn’t really worry about this and just observed the other 3, but showed the drain off for giggles.
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Second is intake side. You can see the first is def leaking, this is after ~30min. 2nd is starting to bead a little. I’ll let this go for some more time and then blow some air at the seats to see what happens
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Gasoline has a pretty low flash point (-45 deg F) so yes evaporation can happen pretty quick. Also, if it was making its way into the chamber behind the valves and getting on the walls that would increase the surface area that it was wetting and increase the evaporation rate.

Most likely it will just take lapping the valves and seats but the guides need to be looked at as well.
 
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