Have to agree with the comments here, a 300 horse NA slant is possible, but to get there you will need: very good port flow, compression in the 11:1 range,
a lot of cam and slant built to get RPMs above 6000.
Dyno Sim will give a reasonably accurate torque and HP curve, if good data is entered. So post the flow numbers and specific cam data and either Rusty or me will enter the data.
And Rusty, concerning "I am still going to have to mill the head pretty good." On the long rod motor I am building, with a very light clean up cut on the block deck surface, the pistons are at zero deck height. Using a non milled head with a combustion chamber cc value of 57 - 58 cc's, The calculated compression ratio is 10.6 to 1
I am planning to run e85 so I believe I am about maxed out on compression. If you will be running race gas, you can go higher on compression, but that brings another set of head gasket sealing issues into play.
Just something to consider.
