Milling 241s
02-11-2007, 04:42 PM
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Milling 241s I am building up my 2002 LS1 with forged pistons and fully balanced rotating assembly and unfortunately the -4cc valve reliefs in my mahle pistons is killing my SCR and DCR. Looks like unmilled my DCR is somewhere in the low 7 range. If I mill my 241s down to somewhere near a 60cc combustion chamber which would require about .050 milled off (assuming .050 as the limit for intake fitment reasons). That should get my DCR into the 8.2 range. Will I be giving up too much in the way of head flow by doing this? I would like to find a set of 243s for cheap but it very well may not be in the budget. If I was to get a set of bare 243s can I just transfer my valves from my 241s (18,000 miles on the 241 heads) onto the 243s along with my dual valve springs? For inquiring minds my cam is a 228r (228/228 .588/.588 on a 112+2).
02-12-2007, 06:43 PM
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You can swap the valves from 241's to 243's
I get 7.63:1 dcr / 9.85:1 scr with 67cc .052
8.26:1 dcr / 10.7:1 scr 60cc .052
8.50:1 dcr / 11.0:1 scr 60cc .040
Thats using a calculator that reads high ..it figures 10.3:1 for stock ls1
I get 7.63:1 dcr / 9.85:1 scr with 67cc .052
8.26:1 dcr / 10.7:1 scr 60cc .052
8.50:1 dcr / 11.0:1 scr 60cc .040
Thats using a calculator that reads high ..it figures 10.3:1 for stock ls1
02-12-2007, 10:11 PM
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Well those are similar to the numbers I calculated but I just gave rough ones becuase I didn't want to redo it. However, does anybody have any idea how this will affect head flow?