Another update from Tod
quote:
I am setting up the 2nd OP and needed to see if I could get a block to clean up for a taller deck. At 9.37 there is no problem at all. That allows it to easily be decked to 9.35. I already have one order for this kind of thing.
I'm also adding gun drilling of the galleys, which is better and faster. I'm adding a 3rd OP to bore the cam and crank as close as possible, being set up off of the decks after they are machined. That keeps the cam and crank aligned with the decks. It also allows me to bore the crank journals after bolting on the caps.
I've been having a discussion with Durabond about cam bearings.
So far my blocks have been built utilizing a #1 journal cam bearing from one set of bearings and #2-5 from another set. The machinists are using Durabond 351HP bearings which are 2.205 OD. They finish 2-5 to use these 4 bearings and finish #1 to FP-26-1 which is a stock size bearing. That way they go straight through and then enlarge #1. Problem with this is that you can't just finish the journals straight through and be done with it. You still have to cut the front one larger. That has GOT to be a pain in the keester.
For those unfamiliar with aftermarket blocks, you can't buy an aftermarket Windsor block that uses stock cam bearings. Using non-factory cam bearings is not unusual. On our 427 FE project, Pond and I changed to a straight through cam bore with bearings that stepped down in ID and there have been no complaints after all these years and hundreds of blocks. It makes finish machining MUCH easier. I'm in the process of determining the preference of builders and machinists in regards to the 351C block.
Durabond told me they could assemble a special package and number for me which is four of the 351HP bearings for journals 2-5 and one of the FP-26-1 bearings for journal #1. That just may be the best way to go, for now.
Durabond says they could make a set to my specs that are the same OD for all 5 journals, requiring only one straight through machining op, but the bearing sets will cost more. They told me they would need an order amount of 200-300 sets to make an "all 5 the same OD" package. In my opinion the extra cost of the bearings is a wash next to the extra cost (and pain) of cutting the #1 by itself. The block will use stock 351C cam cores either way, the IDs of the cam bearings would be the same as the stock bearings. Its the OD of the cam bearings that is juggled to make the block easier to machine for the engine builder.
I am just trying to cut a wide path as the 351C block project ramps into production.
Barry R of Survival Motorsports is getting ready to dyno an engine he assembled using one of my alloy blocks and a pair of Scott Cook heads. The results should be available soon. Anything I learn from Barry will be incorporated into current production.
-G