What lift can stock iron L98 heads handle?

 

This came up the other day. I forget the #, but any time you go up in cams and if you have some milage on the block, it's a good idea to replace the springs.

 

my limit would be in the .46 range, but if they're used springs they need replaced anyway and you ought to get aftermarket retainers and trash the factory set up

 

Will I have to machine to tops of the valve guids for more clearence? I want to use the comp cams 274 grind. .487/.490 lift

 

i'd get rid of the pull out studs and go with screw in. not sure about the valve guides, but i don't think you would, best to dummy it up and check before you bolt everything up for real.

 

from what i understand thats gonna be pushing it. it'd be smart to get new springs. and i dont think you would have to do any machining. im currently gonna run a comp cam xe268h-14 with 479/480 and dont need any machine work for that reason on the l98 heads

 

factory heads can handle about .490 lift. They only got .430 max lift on the MAF cars. The SD cars were .428. So there was no possibility of coil bind.

If you go with a cam like mine you need to get different springs. My stock valves were used also, no grinding.

 

Thanks for the help.