The engine was definitely bored and from what I can see with my simple gauge is that it is .040 over.
Original Equipment Quality
With a long history of producing engine components dating back to the early 1900’s Hepolite is well known for engine parts for many classic British vehicles, many of whom were supplied as OE with Hepolite branded pistons, rings & bearings.
The Hepolite range consists of pistons for many classic British vehicles, all of which are manufactured to the original specification. With interest in classic vehicles at an all-time high and values increasing, it makes sense to repair these vehicles with the same quality of parts as when they left the factory, therefore helping keep the value of the vehicle.
This set of Hepolite Aluminum Pistons are .040 over for a total piston size of 3.5625 plus .040 = 3.6025. So my cylinder bores should be about .002 over the piston size (3.6045) if it is all going to work as is. I will need to use a tool to properly measure the bore size.
In the meantime I tested a piston in a bore. It was snug fit but there was still wiggle room. So I inserted a .002 feeler gauge in with the piston and it made the fit tight – or so it seems. I want to do a proper measure to be sure all is within specs. That will happen a bit later.
The main bearing caps look ugly but they’re not as bad as they look in the photo. I plan to sand blast the outsides of the caps first. I’ll then install them in the block and using the cylinder hone and lots of solvent lubricant I’ll carefully hone each just enough to clear out the ‘patina’ of rust in the bearing seats.
This is a poor photo, but you should be able to just make out the surface rusting in the lifter bores. I plan to use a small 2 stone wheel cylinder hone to once again just clean out the rust from each bore. I did test fit one of the valve lifters from the JT engine and the fit seems tight. Strangely I have yet to find the lifter bore clearance specs in the Studebaker repair manual. I’m digging online but no luck so far.
A shot of the shelf in the background with all the JT components. Lots of work to ready those parts!
Here is an interesting intake I picked up in my travels. It is a highrise two barrel with a Stromberg WW carb. Likely used on the early V8s. I’m not sure if I’ll go with the original JT Carter AFB on a flat intake or go for just a 2 bbl on a highrise. If I could find a larger 2 bbl carb that would fit on the original intake base I might go for that. Unfortunately a Holley 2bbl won’t fit without some serious machining. Jim Pepper says “The R1 intake does not have slots in the plenum divider so throttle response should remain somewhat crisp” He later comments that a 1/2″ to 1″ spacer under the carb will help with fuel flow and reduce separation of the air and fuel as it bends at the floor of the intake. Decisions, decisions….