Heads are 2 ltr, drilled and filed, for better cooling flow.
Popular Hot Rodding, issue Nov. 2003, article Titled, The Power Squeeze, it's about ceramic coating your combustion chambers, valve faces and exhaust ports, and alot of other helpful information.
The ceramic coating helps keep the intake charge cool. Example: your plug fires ignites your air fuel mixture heats up your chamber, piston goes down, power stroke, piston comes back up exhaust stroke, exhaust opens, hot exhaust exits, heating the exhaust port, which is right next to the intake port, heating it up and the intake charge, intake valve, fairly large, is heated by the combustion in the chamber, intake stroke, intake vale opens, valved is cooled by the intake charge, intake charge is heated up by the hot intake valve. Cooler the intake charge the better, allows more compression. Just like turbos, the bigger better intercooler, allows for more boost.
It, cost me $35.00 a cylinder to have them coated plus shipping, the companys name, POLYDYN COATINGS, there in Texas, website,
www.polydyn .com. Check them out. They were in the article. One of the engineers at JE turned me on to a place here, it's called Specialized Coatings, there in HB or CM I have ther # .