advice

Are they the dome hi compression pistons? (see pic below) let me guess it starts comen alive apx 3000 rpm then screems to about 6000 rpm right? if timing,carb tuning & such are good got 10 bucks sayen yer stock converter is waaaaaay to low of a stall. my set up has a 2500-2700 stall & its almost enoph. 3.55's or 391's would help alot! or get a later 904 that will accept the wide raito planetry (2.76:1) 1st gear raito. Whats yer cranking compression?