Well, first off I have to admit that my spreadsheet which I use to calculate all of my expenses to date had an error. The correct price of the pistons, piston rings, piston pins, Tru-Arcs, and shipping was $380. I forgot to add in the $100 deposit!
Perhaps you folks on the West Coast, in the land of hot cars, can find forged pistons, etc., cheaper. Here on the other West Coast (of Florida) the auto hobby is barely creaking along. When I find something I need, I don't always have the resources to shop around. While I am at it, a big thanks to Ramon Spontelli for orchestrating the ARP connecting rod bolts. Thanks again!
Anyway, here are the particulars for those interested:
Venolia Pistons & Rods
A Division of TOR-CAM Industries, Inc.
2160 Cherry Industrial Circle
Long Beach, CA 90805
As I mentioned previously, the head I am using has been milled and the combustion chamber is smaller than normal. I want a compression ratio of approximately 10.5 to 1. To achieve this ratio, I calculated the following:
CR = C-P+G+D+V
C-P+G+D
where
C is combustion chamber in cc's
P is piston dome displacement in cc's
G is head gasket displacement in cc's
D is deck height displacement in cc's, and
V is cylinder displacement in cc's
I calculated my combustion chamber to be 33.4 cc's; used a .020" deck height; estimated the head gasket thickness to be 0.038" compressed to 0.025"; and used a piston dome displacement of -6.5 cc's. This combined with a 3.25" stroke and 3.2402" bore gives me a compression ratio of 10.55 to 1.
The -6.5 cc's answers Jarrid's question or comment regarding whether or not this piston has a dish. Yes, it does...I would have liked to run a flat top, but I just couldn't. If I can decipher the order form correctly, I believe the piston pins are 0.94", slightly larger than the stock 0.9377"
I will use a Kent Cams Scatter Pattern 286SP Rally cam and Crane dual valve springs with the following specifications:
.315" cam lift inlet
.324" cam lift exhaust
.388" valve lift inlet
.400" valve lift exhaust
I was able to obtain one of the last dual Webber intake manifolds (for use with 40mm DCOE's) from Holbay before they went belly-up.
I am NOT an engineer. I hope there is not a fatal flaw in this calculation. If you find a fatal flaw, please be kind.
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