Trying to figure out dynamic compression ratio and safety for boost on the new build. I used the wallace calculator, but want to confirm I am correct on this if someone can help me out.

hardware: BC rods, wiseco 96mm 11:1 pistons, tomei 280/11mm intake and exhaust cams.

using
bore: 3.77953"
stroke: 3.204724"
static CR: 11:1
inlet valve ABDC: 85
boost: 0
target altitude: 0 (i am at 6000 ft but want to get a sea level measurement). Im sure higher altitude=lower CR

I am getting a DCR of 7.15 with this. If that is correct then I should not worry about going for high boost.

any help on this would be appreciated.

 

The bigestimate question is what fuel are you using

 

appreciate your effort conway, but tbh, with all that has happened with your build so far, looking for someone else to chime in.

I will be using 91, but can get access to e85 or race gas for dyno purposes if necessary. Just not easily accessible enough here to daily e85. also fuel matters yes, but the determination on fuel needs/realistic safe power goals will depend on the DCR.

 

Good point :-(

 

common cams for our cars have so much overlap, that when i did the math, up to like 13.5:1 still had DCR is the "safe" range.

No one runs that high, but strictly by the DCR guidelines other platforms use, we are very very conservative.

 

thanks! I figured the calculations were correct, but it seemed too good to be true. I guess I should be able to use high boost on this setup and not be too concerned as long as I have enough fuel and a good tune.

Of course, max potential would require race gas/e85, but I should be able to hit 6-700 on 91 pump then as others are.