Does anyone know if there is a difference between Block ROck and the Moroso stuff as far as utility? Block Rock makes some claims about expansion rates etc. Is there any practical difference?
I`ve never heard of Block Rock, (could you be thinking of "Hard Blok"?) I`ve also never used the Moroso filler, but I have used 2 different styles of block filler. Years ago I filled one of my 428`s with a concrete based filler that I bought from a Northwest Stock FE racer/engine builder. With this stuff, the filler needed to set up for a couple of weeks prior to machine work, as it really pushed the cylinders around. Eventually it split a cylinder wall anyways. The 302 in my 85 Mustang Stocker has been Hard Bloked since we put it together in 2004, and after splitting 2 cylinder walls in the Fairmont last year, I surrendered, and it got Hard Bloked early this year. (Thanks Gord!) Although any block filler should have ample set up time, and be done before any machine work, with the Hard Block it doesn`t seem to be as critical, as all the machine work on the 428 had been done a couple of years ago, and when my machinist buddy honed the cylinders after the 2nd sleeve was installed and the block filled, the cylinder walls cleaned up quite nicely, and the car is running just as fast.
428 powered Fairmont drag car, Best ET:10.03@132.11MPH, best 60 ft: 1.29
59 Meteor 2 dr. sedan 332, Ford O Matic
74 F350 ramp truck 390 4speed