Thread: Internet CR calculators question

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That should be the number...but it seems awful big...It may help if you do what Denny said and post what cam this is.....and some other specs about the motor.This is the time to get it all figured of with no doubts!!!!
Theres alot of people on here with calculators and converters to help and they may not be familiar with that specific calculator/converter.

The cam I used had a number of 57 degrees and called for a static of 9.5 to 1 to 10.5 to 1 compression.I also used rhodes lifters which lowers this number further under 3000 rpms.

Cam is modern replica of the L79 hydralic,447/447 lift, duration @ .050 222/222 with 290/290 adv.duration (some list at 306 instead of 290???);valve timing @ .050 intake 1*/41* (open/close); exhaust 49*/7* (open/close); valve timing advertised, intake 40*/86* (open/close);exhaust 88*/38* (open/close).
Motor is 4.00" bore/ 3.00 stroke; pistons are original static 11:1 when used with 64cc heads but I "might" try to use a set of 58cc heads "if possible",if not then 64cc but I am using 58cc for the 'cyl.head vol.' figure in the calculator. Gasket thickness is .016"; gasket bore 4.166"; deck clearance is a 'measured' .025"; and 5.7" rod length. This will be a weekend cruiser on race gas,cam 2 or so,,,
So Shawnlee 28 if you or anyone else would be so kind as to compute and advise it would be much appreciated.And notice my italics,,,,I know a degree wheel and precise building measurements will be required.Thanks,Jerry.

Here is one that I used ,it calls for the .050 numbers that you already have!!!
http://www.wallaceracing.com/dynamic-cr.php