I have read that you just use a file to knock the guilds down to what you need plus some clearence. Do the guilds just slide out? How do you get the guilds out far enough to file them. Do do you just start filing away at the top, I thought the actual guild was inside but maybe not. Thanks and what is a good compression ratio with the XE274? 91 octane is the only fuel and this is with vortecs great combustion chamber
I'm not sure if I understand, but do you mean for spring clearance?
If so, then no modifications are necessary. Many drop-in springs are made by EPN, Comp Cams, and so on...the ones by EPN can take .600 lift and have 110-120lbs at 1.850", which should be good for that cam.
I found the post over on chevelle from Gary at GMPP which says to add more clearence just file down the guilds and becareful not to take too much, just take enough for clearence and a little extra for safty. I just dont know where to start, do you just start filing away on the top?
I suppose you could just file .025" off the top of the guides, just remove the valves and file the tops, I would deburr the inside after filing. It will be difficult to make the top look like it was machined. and will be a lot of filing. and clean up carefully when you are done.