When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a 1953 F100 with an 8BA flathead V8. I believe the heads are standard 8BA (although they are not marked as so) with the 6.8:1 compression ratio. I also have a pair of EAB heads with a 7.2:1 compression ratio (smaller combustion chamber). The EAB heads are said to have improved flow and compression. Does anyone see a potential problem replacing the standard heads with the EAB ones? Will the higher compression ratio effect the lower end significantly? TIA
EAB heads would have been OEM on a '53, AFAIK. Absolutely no problem using them on your engine. The bump in compression and flow will absolutely not cause any harm.
That said, can you tell if the EAB heads have been cut, either for flattening or to further bump compression? If you look at the underside near the thermostat part of the casting, there would be a definite difference in the level of the gasket surface and the casting for the thermostat/water outlet. As heads are milled (surfaced) there becomes less of a difference. See pics. The concern is that with an excessively cut head, and a non-stock cam, you may need to check for valve head clearances to the combustion chamber. (Note this is true with 8BA heads, too) I am running EAB heads on my truck.
I don't know the history of the engine my truck. The only markings on the heads other than casting numbers are a capital letter F. I have also noted that the markings on top of the head bolts vary from a standard 3 striped grade 5 marking to a Ford marking, a 1040 material grade and even a few others. I didn't realize that EAB heads should have been on this truck and it looks like maybe the heads were changed out at some time in the past.
The difference in the surface level at the thermostat area is definitely there. It measures about .040 inches. Do you think this is enough of a step to indicate that the heads have not been milled before? Thanks for your interesting and useful information.
Unless you are using a high lift cam you should be fine.
Make sure your bolts that go in the center of the heads (between cylinders 2-3 and 6-7 over the exhaust crossovers) are OEM or at least OEM length. Those holes have closed bottoms and if the bolts are too long you could crack something or strip the threads.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
