We are working on stuffing a GMC back into the Salt Circus Roadster. And GMC stuff is not SBC stuff. Few and far between. And for the Fergusons, and they are friends and I can't afford them. They have the molds and they do cast them from time to time, but they are heavily involved with the ARDUN stuff cause GMC guys got no money and the flathead guys do. PM if you are really serious about a head.
LOL its not a poncho, or a rocket or a an FE or a caddy, or even a 235 either. Kind of a dumb ***ed remark in my own personal opinion of course I already know that it is not a V8 of any sort or the most commonly used inline 6 either. The OP probably doesn't know that.
dtwbcs: sorry but GMC's are not rare, there not even hard to find if you look and ask around. Yes today they cost a little more and people who have them, many of them like me are glad we do. I sold a complete 302 for $800 2 yrs ago and probably should not have. I had a guy give me 4 sets of rods last year. I bought 10 iron and steel cams for $20. Yes the steel ones are worth 2-250 if your racing a flat tappet and need it. If you want a 12 port with rockers, an injector, cover and side plate about 20K will get a few guys I know that have them at least talking to you. The best thing to do is get a 228" and you'll have a all the tin, pumps, and internals you'll need as the're all the same. Good luck and don't give up....
I think Jim has pointed out before 270s are cheaper than 302 engines. They were made over a longer period of time. And in my experience, run about as well as a 302. Especially on the street.
I have a 302 in the shop, to be rebuilt right now. Will take my 270 out of the truck for parts. Was just trying to dress it up a little.
Rich, am I right in ***uming that a 270 can be bored to 302? I have a 270 that was given to me about a year ago, and know the whereabouts of several others inexpensively available.
Before I opened this thread, I thought you were talking about the GMC V6 302 and wondering why you'd choose one as a street engine. Whew!
No. In the day many 270s were bored .156 over to 3 15/16 which made a 292 inch engine. The 302 had a 4 inch bore and a 4 inch stroke. Same stroke as the 270. But as you say, they are relatively inexpensive. Look the same as a 302. And run about as well. My first GMC was a 270. I ran the heck out of it. Still have an El Mirage record with it. Just be careful not to get a very early one with the 4 bolt flywheel/crankshaft. Flywheels are available for the 6 bolt flange which is the same as the 302.
Be careful on boring a 270 as Rich said. I have one of the last 270's out to 3-15/16" and already has one sleeve and needs another. But saying that I would put in all 6 sleeves because I have the hi comp pistons and rings. Any time you are building a GMC 6 now days you bore it to the ring/piston combo you can get. I have a 1940 270 block ( the first year) bored to 3-31/32" to be in a under 300" cl*** of racing in the late 40's early 50's. It can be safely bored to 4" I was told but only the earliest 40's blocks. It does have smaller main bolts and caps. It was my first engine and I still have it. All cranks inter change. The are only 2 strokes and many 302's bored to 4.125" have the shorter stroke making it a 306" I believe. Rich is correct on the crank flange. The 6 hole sure makes it easier and some 248" cranks have 6 and some have 4. I'm not sure on the 228". One again good luck.
Recently pulled a half ton '53 hydro 228 - 6 bolt flange. Not sure what the '52 step vans had. If not mistaken, the '52-'53 302 is 6 bolt. So many of these engines were patched up in farm rigs that it's unusual to find them intact. If anyone is looking for a complete Korean War 302 (the one with the big port cyl. head), I'd be happy to run one thru the cl***ifieds. The V6 mentioned above is a 305, noted for delivering 8 MPG in a loaded 10 wheel spud truck or an empty 1500 pickup ...
Every 302 i saw had a 6 bolt crank flange. One 270 I had was 4 bolt. I had others that were 6. I worked on Koren war era deuce and a half 302 powered trucks enough when I was in the Army. they were getting pretty old by then.
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