Engine Assembly Question, Which way do the pistons face? |
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Engine Assembly Question, Which way do the pistons face? |
ThinAir |
Mar 27 2005, 06:10 PM
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#1
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Best friends Group: Members Posts: 2,543 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region |
I'm about to install the Mahle Euro (flat top) pistons and cylinders. I know that it is critical to have the pistons facing the correct direction relative to the flywheel. I'm used to seeing an arrow on top of the piston that is supposed to be pointed toward the flywheel. These Mahle pistons have no such marking.
This picture shows the top of the piston. Is that funny little symbol supposed to represent a crankshaft & flywheel? Is it critical which side faces the flywheel end or just that all the pistons are the same? I'm hoping someone answers quick - I'd love to get the heads on tonight! Attached image(s) |
ThinAir |
Mar 28 2005, 12:20 AM
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#2
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Best friends Group: Members Posts: 2,543 Joined: 4-February 03 From: Flagstaff, AZ Member No.: 231 Region Association: Southwest Region |
That's OK Joe. I want to understand why, not just be told what to do.
However, in this case I'm having trouble working through this myself. I'm afraid my poor Algebra skills are coming back to haunt me. This is a stock engine in every way except using Euro pistons instead of stock pistons. It's my understanding that this gives you slightly higher compression using stock settings in every other way. The stock CR is 7.6 and the pistons are 94 with a stroke of 71. Using the Engine CC formula it comes out to the expected 1970.9 cc. So, substituting those numbers in the CR formula I get: 60 cc + deck cc + 492.7254 = 7.6 solving for deck cc I get: deck cc = 7.6 - 60 - 492.7254 so that would make deck cc = -597.5254 which obviously makes no sense! So, assuming you are building a totally stock engine, what should the deck height be? |
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