What clutch are you using on your early 273

There is no good clutch for the 122 tooth flywheel. With a 273 I would suggest that you upgrade to 130 tooth flywheel, clutch and bellhousing.

The 10" clutch from Brewer's is not performance oriented. I know, because I asked them. The .org site is trying to do a group buy for a new design from Ram. You may want to check it out.