https://www.instagram.com/p/CGLXRIdjRXi/?utm_source=ig_web_copy_link Hope the link works. Not an 848 head, a ported 913 head from 1954 on a 1962 261 block.
Feels great. Will have a Clifford four barrel intake with a Holley 390 cfm, the Clifford will mate to an early style integral heat Fenton Header.
848 head is the “ good head” for 235’s bumps the compression up by a 1/2 point. but any 235 head on a 261 is an improvement. Over stock. did you drill the steam holes in the head?
Here’s the mock-up of the Clifford intake with Fenton’s. I have a machinist friend who married them together.
Both the Clifford intake and the Fenton header are the early versions. The Clifford intake changed to a water heat version in the later version. The 235-261 Chevy Fenton headers changed to pipe plugs to access exhaust heat to prevent icing in the carburetor base. I can only guess that in both Clifford and Fenton’s reasoning they went to a ‘universal’ application because IMHO, close is not good enough when it comes to exhaust leak. My machinist friend made these two now rare pieces ‘gasket perfect tolerance’. I now have 115 k miles on a 1956 235 so it will be fun with a 1962 261 with the set up above.
In my case I bought an engine with a 913 head it was ported and polished which is a science unto itself.
Gotcha! I have my dad's 261 with the 848 head that Jiggs Jenkins (before he was known as Grumpy) ported and polished back in the 60's. Unfortunately, it's hosted multiple generations of mice in the head, so I'll have some work to do
I am tearing a 41/46 truck up and found that it had a 261 block and a 848850 head. I was wondering where the 848 head was origanly used. Looks like 2.02 intakes. I have done several searches but no luck. Any help?
Read the casting # again - it has 7 digits. After 1956 on the 848. Intake valves that big would take some pretty serious machine work. Then post the pictures of it here ...
There is no real difference in port or valve size between a 850, 913, or 848. Just the size of the combustion chamber. If you mill them, you lose the relief area from the intake valve into the combustion chamber. Top pic is a 850, bottom a milled 848. I'd rather use the 850 or 913 and use a pop up piston to get higher comp ratio. 850 head has the steam holes which must be drilled when adding an 848 to a 261.
My 1960 261 is the Canadian Pontiac base line version, and it has the factory installed #848 head on it. Dyno Dave