CC displacement

[SCOTT WITHERELL]

? if I have a 34mm piston and a 29.6 Crank, how many CC will it be now. (Stock Crank 28.0 with 34mm piston,, 26cc)and if you can why the long stroke Mod, Please shed some light on this (laymens terms .{My Lights are dim, but I'm home },,LOL . and how it affects timeing and comprestion, new to Gas Motors. thank you.

 

[Dennis Somers]

Scott a 34 x 29.6 will net a 26.87cc. If we are talking specifics, the 34 x 28 is a 25.4cc ( everyone calls them 26s ). The longer stroke will add ccs obviously, increase torque slightly, and add a little power. It does this by VERY slightly upping the port timing and adding more crank leverage. If assembled carefully ( proper clearance checking ) it will increase compression, and that can be felt with quicker response.

Gas boats are sensitive to torque ( more than nitro ). And over-all set-ups are critical for the best results. I say this because adding ccs. is no guaranty that YOUR set-up will be faster or handle better with a bigger engine. I hope that helps ya.

 

[SCOTT WITHERELL]

Thank you ,Dennis, , that help a lot..

 

[SCOTT WITHERELL]

Found this ,,( https://spicerparts.com/calculators ) was great to find out different engine configurations. on displacement.

 

[Dennis Somers]

Good find Scott!

Here's another; put yer feet up, this will take a while LOL ...
http://www.wallaceracing.com/Calculators.htm