cranking compression on alcohol motor, cam advance question

[dbusch]

4800 converter sounds very tight. plus, with a sheetmetal intake, i dont see why it wont make power past 6500. those heads do have a small cross section past the pushrods, so that might be it. plus, with such a tight converter most engines dont respond much to a higher rpm shift. i wouldnt pay much attention to what the chassis dyno tells you. there is too much influence from the converter. going to an engine dyno would tell you what you need to know.

then again, the rpm problem might be the valvetrain: the TK lobe is going to generate the highest cranking numbers of any lobe Comp has. when using this, you need to go at least 5* larger than usual to get things in the right ballpark, so it would need to be more like 272/282. i wouldnt use a big rocker either, a 1.6 is probably best for something that aggressive. looks like you are using a .455 lobe with a 1.7. what spring are you running? my preference is to use a slower lobe, assymetrical with more rocker arm. the RX would have been a more rpm friendly choice. seems to me that manifold would want more rpm. the headers might be a touch small to go past 7K as well.