[updated:LAST EDITED ON Mar-30-06 AT 01:13 PM (CST) by Robert (admin)]I just bought an early 60's (283 and everything that I can find about it says that it has 1.72 int and 1.5 exh valves.I measured them out and the intake measures a hair under 1.75 and the exhaust measures just under 1.5 I have never heard of a 1.72 intake ,has anyone else? motor id# 3789935 head id# 3795896
RE: early [updated:LAST EDITED ON Mar-30-06 AT 01:24 PM (CST) by Robert (admin)]3789935 = 283 1961-64 two bolt main 3795896 = 1963-65 283 block 60cc chamber DVal
RE: early [updated:LAST EDITED ON Mar-30-06 AT 01:14 PM (CST) by Robert (admin)]What's up with the POUND Signs ?
RE: early 283 was one of the best motors chevy ever made in the 60s wish they could bring it back start making them again...
RE: early Apparently this forum doesn't like Norton Internet Security. Anyways, what I need to know is if anyone knows where to score the 1.72 intake valves.
RE: early Simply not necessary, 1.75 will work fine, and would actually be better because the machine shop can use a 60 degree cutter to move the seat area out and then the 45 degree stone can give you a new seat the desired width and "unsink" the valve. All this is going to be so slight since .003 is just .0015 on each side. A human hair is .007 so the difference is nil. When we raced 283's we would cut them out to take the 1.96 valves with no problem but not the 2.02 because they wouldn't work with the 3.875 bore without notching the top of the cylinder. The rodders for years have used the three angle valve jobs(60,45,30) for hp gains. The 60 degree cutter is used to move the seat out to the maximum size valve the cylinder will accept.
