Anybody in hamb land running one of these ? Me and my dad are picking up a 270 sat. I would like to see pics of them souped up. Thanks
Patience Grasshopper! There HAVE to be some GMC guys on here... and if you give up on it, I'm looking for 270 pistons
I have a GMC 302 with a 6-71 blower and dual carbs. Basically the same engine just a larger bore. In fact my 302 is running a 270 crank and rods. Although everything else is 302. Here's a pic.
By http://img88.imageshack.us/img88/461/ebay1487.jpg[/IMG] By null at 2010-05-14tp://profile.imageshack.us/user/null]null at 2009-10-09 yea i got one
Wow! that thing is cool!! what kind of hp / tq does it put out? add - heh 2 blown 6's that looks a little odd with the blower not in the center though. but i LOVE it
I don't actually know how much HP/TQ it puts out, I've never had it on a dyno. But my engine builder guessed that with 5lbs of boost, which is what I run as it's a street engine, that it probably puts out in the neighbourhood of 260-290 hp. It pulls really well. I was doing 50 on the hwy and wanted to pass a big truck, so I stepped on it and was doing 80 before I knew it. It really moves. Personally I like the blower off to the side. That's part of what makes it different. It sounds really nice. I have nicson knock off cast iron headers, dual exhaust and smitty mufflers. So it rapps quite loud on deceleration and sounds awesome under power. Edweird: If you're interested in the specs of the engine you can pm me, i'm not sure too many others on here are that interested...lol
I'm interested! Post the specs up. I'm in the early stages of building a GMC 302 for my 35 Ford pickup.
Hey Quicksilver. I'm in San Mateo and ran my GMCs at Bonneville and such for a number of years. Still have a El Mirage record. Your project sounds pretty interesting.
I've read a number of your posts while doing research about the inline GMCs. I've love to get together to pick your brain and learn about these engines sometime.
Ok, so when I was looking for a 302, I had a really tough time finding one. Being from BC Canada, there's not much in the way of these old engines up here. So I ended up buying a complete 270, a bare military block and a complete 302 head. Since the 270 has the same stroke as the 302, I used the rods and crank from it as well as the camshaft and a few other parts like the oil pan water pump etc. There's not much difference in the military blocks, other than a few more bosses and threads for PTO's and stuff as compared to civilian blocks. I would have liked to have a cross flow head too, but once I started doing research into them, I realized that was a pipe dream considering the rarity and cost. Even the Arias ones are expensive. Compression: 7.8-1 Arias forged aluminum flat top pistons Stock rods and crankshaft Stainless steel valves and pushrods: 1.84" intake and 1.6" exhaust The head has been ported and polished The camshaft was reground by a local grinder with a conservative grind as it is driven on the street as well as blown: .309 lift intake, .295 lift exhaust with 113 degrees of lobe separation. The ignition is a dual point mallory unit with an MSD box hidden behind the seat. Dual Edelbrock 600cfm carbs Philips Performance cast iron headers (nicson knock offs) The blower manifold is actually a cast aluminum 4-71 unit that is supposed to mount the blower vertically that I got from the old Stovebolt engine co. It was his last one which he found at the very back of a dusty shelf. I had a machine shop build and adapt an aluminum plenum(with a pop off valve)to the manifold so that the blower mounts horizontally. The Valve cover is a two piece unit that I found at the Portland Swapmeet. Apparently only 60 were made as the guy making them couldn't make them pay for themselves. I only paid $60 for it and it was his last one. The side cover is a custom finned one I had made as vintage finned aluminum ones are fairly rare. A lot of the pieces on the engine were custom made to make it all fit and run right. It cost me 3 times as much as I thought it would and took me 5 years to build, mainly cause of money. That's about it.
Hey Deucedreamer, I hope you dont mind but I re-posted your Specs (and photo) over on the "The Ultimate 235 Hop up Thread....... " I am sure those guys will get a kick out of your engine build.
Many say that Patrick Dykes is the GMC 6 guru; http://patricksantiquecars.com/ http://www.oldgmctrucks.com/ is also a useful site, though I don't think very user friendly. They do have a lively discussion forum. http://stovebolt.com/ is also a useful site with a popular forum, but it is more Chevy oriented.
hERES A PIC OF MINE.. 29 Model A sedan made into truck. 302 GMC bored .125 for a 322 cu in. Howard camshaft,Jahns pistons, Nicson headers , four speed with quick change. Have driven for the past six years ...been a good one AND its fuel injected , TBI hidden under the air cleaner...........
ok fellas, got a the 270 today for 300 smackers, does any body know where we can get an adaptor to put a 700 r 4 behind it ? i want to use a 5 speed, but pop says he's to damn old to mash a clutch.
Buffalo Enterprises. Not cheap. Maybe you should swap that 270 for a 292. The 700R4 will fit right on it.
Buffalo Enterprises in Washington makes adapters to bolt up 'Glids, turbo 350 and400 or stickshift blowshields for Chevy V8s. Would the 770 R 4 have the same pattern? 360-652-7684
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