The pistons look good. Did you measure the bowl volume like we talked about, or did you do something different?
LB7: Motor Build thread
- Thread starter TrentNell
- Start date
I am going to , I made the stuff to test it but , the CC #'s werent aplicable to use Guys spreadsheat like i thought they were , but Johnboy crunched the #'s and helped us come up with the 2.6 dia. :hug: , now i just want to double check the CC's and figure out the actual compression ratio and see how close we got .
Thanks for for all your help , and if you know a way to figure CC's to actual compression ratio i am all ears :teknology::rofl:
I'll have to sit down and figure it out, but I'll see what I can come up with.
By my calculations, your stock combustion chamber (meaning the volume in the bowl, head, and head gasket) has a volume of 3.06 cu in (50.14 cc). To get a C/R of 15.0:1, you would need your combustion chamber to be 3.60 cu in (58.99 cc). So you would want to take .54 cu in (8.85 cc) out of the bowl area and leave everything else the exact same (same head gasket and same piston protrusion).
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Good luck Trent I've been reading the thread, I hope it's abeast when your done, I'm subscribing, I'm sending you all the positive energy I can dude, Oh an thanks for sharing this with us.:thumb: :thumb: :thumb: :happy2:
I like the looks of those pistons:thumb:
What gasket are you going to run? gonna play it safe with C's? Or squeeze some more out of it with A's?
What gasket are you going to run? gonna play it safe with C's? Or squeeze some more out of it with A's?
I like the looks of those pistons:thumb:
What gasket are you going to run? gonna play it safe with C's? Or squeeze some more out of it with A's?
Gotta check protrusion first , and see what the pistons come in at with the CC test to see which way if any we need to cheat .
You may end up having to trim the top of one or two to get all the protrusions close to the same. I had to on my last build.
Also have you thought about CC'ing the "cup" of each piston? I think it would be pretty important to attempt to keep the volume of each as close to the same as possible.
Also have you thought about CC'ing the "cup" of each piston? I think it would be pretty important to attempt to keep the volume of each as close to the same as possible.
I had planned on checking all the bowls and go from there if we have to even any up . and I guess we will see how the protrusion check goes , if we need to shave a few its not a big deal .
I will measure one but there are pics in this thread of the pistons before i cut them .
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I had to fly cut 6 of mine, I set mine .012 out of the hole, I just cut the lip off my, I was trying to keep a daily driver application, I really enjoyed doing that stuff,
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so what do you do after you cut the pistons?? are they dipped for more heat control or is this all you do?? nice thread trent, keep up the good work:thumb:
Yep
That is all you do , take away the area that holds heat ( lip ) and reshape to get the lower compression . High temp coating is a good idea also .
Sounding great Trent! How did the Rod bearings and Journals look at 70K? Any scaring on the crank?
