Yeah, that's what the guy with the truck was saying too. I think I'll put the 4 speed I've got in it and keep my eyes peeled for a 3 speed. If I find one, I'll do what Don did. On paper, the car should do fine without it. With a pair of 7X10's on the back (~101in circumference) 2650 rpm would put me right about at 75 mph. The overdrive (.85:1 ratio), would only bring the rpm down to 2250 to go 75 mph. It helps, but I can live without it.
Okay, I'll stick with the small port manifold then. I can see how leaks could become an issue with the big port one...
My grandpa's "How to Hop Up Chevrolet & GMC 6 cylinder engines" book from 1951 shows that the head can be milled up to 1/8 (.125) of an inch. They also say that with the stock pistons milling off .080" will bring compression up to 7.5:1. I'm only looking for about a 9:1 compression, so I suppose we could do the .080" mill and the rest with high dome pistons. This seems like an awful lot though, I was thinking it would be around .030" too. The amount of weight we are saving is so minuscule that it may not even be worth the money to plain it at all. It could all be done just by the pistons... I'll ask around some more...
Beater of the Pack: Wow, that must have been a nasty wreck! Glad she's okay! What a honeymoon! What a steal for that '41! $800 bucks? That's incredible!
Don 1450: That old '40 would be pretty sweet with a 302!
One more thing, Beater of the Pack, some guys from the HAMB were disagreeing with you about the small port 270 head possibly performing better than the big port. My thought was maybe that the big port would flood easier, but I'm not sure. If you'd like, you can straighten them out. Here's the link:
GMC Straight Six Questions Thank you guys so much! I really appreciate it!
Pete
