Pretty sure there's not meant to be a hole here...
#26
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Low compression = big timing advance = big power and low EGTs = durable
#32
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Milling the head reduces the size of the combustion chamber and increases the compression ratio. What makes anyone think otherwise? It is how people have increased compression ratios since before Fords were flat head v8s. I've done it to increase the compression ratio on several engines I have built over the years.
What is going on here? Am I accidentally on m.net or something?
What is going on here? Am I accidentally on m.net or something?
#34
For the ease of the example.
Piston has 9cc and 1cc space in the head.
So it takes 10ccs (piston + space in head) and squeezes them into 1cc. 10:1
Same piston bigger head.
9cc piston 2cc head.
So thats 11cc and squeezed into a 2cc head. Whats 11 squeezed into a 2cc space?
5.5:1
5.5:1 is LOWER compression ratio than 10:1.
Overboring pistons on the other hand RISES compression.
Over bore the same piston to 10cc so thats 11cc total (overbored piston + regular head) squeezed into 1cc space.
11:1 ratio.
Err wait you mean shave off the head...
#36
Yes, also known by the rest of the world as milling the head.
Typically you grind in the chambers to cc the head. Taking out more than a couple cc's is considered rather extreme and thus the amount it changes the compression is not a large factor.
Your piston argument is moot because you aren't going to shove the same piston in a larger hole, and the requisite new piston will have its own design and thus effective compression ratio.
Or you could just be trolling in which case I'm a ******* moron for taking the bait.
Typically you grind in the chambers to cc the head. Taking out more than a couple cc's is considered rather extreme and thus the amount it changes the compression is not a large factor.
Your piston argument is moot because you aren't going to shove the same piston in a larger hole, and the requisite new piston will have its own design and thus effective compression ratio.
Or you could just be trolling in which case I'm a ******* moron for taking the bait.
#39
I feel like we need a time machine so the new members can go back 18 months and relive the forum discussions where it was proven that dropping compression to 8.5:1 increases torque across the powerband by allowing significantly more timing advance.
Low compression = big timing advance = big power and low EGTs = durable
Low compression = big timing advance = big power and low EGTs = durable
any particular threads of interest?