The Stovebolt Site Forums The Shop Area Engine Shop GMC 228

I have a 228 which I am ready to pull for rebuild. I have already had the head installed with hardend valve seats for unlead 2 years ago.
I have thought of boring this out and putting in a better cam. Also installing dual exhaust and dual carbs.
Am I just [censored] money away? I want a bit more jump in the motor, but not looking for a NHRA record holder. Should I just rebuild it stock and seek another block, 292, to soup up? How about GMC 302?
Any suggestions will help. I don't want to waste money and end up disappointed with end results.

A GMC 248 or 270 would be a lot easier to find and get parts for than a 302. Even civilian 302's are sometimes hard to stick in a small truck. Military 302's are a PITA. A 292 would be lots easier to find and build than a 302, if you don't mind sticking a Chevy motor in a GMC, and lots of folks would argue that it's a better motor.

The Stovebolt Forum has a great search function. I'm sure you could come up with some info on 228 tweaks. My hunch is that you could cheaply do pretty well just sticking with your 228.

I would also recommend joining the following forum which is dedicated to old gmc's. The guys there will be able to answer all your questions.

http://www.oldgmctrucks.com/page0026.html

http://www.inliners.org/ is pretty good too.

If you look at the gallery photos of my 39 there is a 228 in there
It was a nice engine with better than Chevy power and very good
mileage.228's and 248's both suffer from a very heavy pistons and less than wonderful combustion chamber shape.
I drove the 228 as an original stock old used-up motor to hopped up blueprinted Chevy eater. It was fun
When I had the chance to go to a 302 I did it.
292 just won't make the power and torque of a 302
You want cheap power go to small block Chevy
You want class stick with the GMC six

I use Nicson intake and cast iron headers and an Isky cam

I would think of a 270-302 head on a 228 with flat top pistons
kindda a nice mix of parts and power.....and mileage

And get ready for Long Motor Envy from the guys with little car motored trucks

It's all fun!!!!

302 gmcs are easy to find. You just have to look. I have three running in trucks and two in parts. All within one hour of home. The only disadvantage of the military is the lack of mechanical fuel pump and you'll have to swap the pan and oil pump pickup. Big deal. You'll be money ahead with a 270 or 302.

At an ATCA show last summer I found a guy with a couple of 302s for sale in the couple of hundred range. I've had a number of people offer to sell me 270s when they learn I have one.

Finding these motors doesn't seem real hard. What holds me back is the expense of rebuilding and modifying them.

As for the 228 vs 292, I think I'd choose the 292. But then I plan to replace my 270 with a 454, so many will think I've a warped sense of what's right and wrong.

Hey J.H. Profitt

I was wondering why the 302 makes more power and torque than a 292. I have a 302 in my 51 GMC 1-ton but I had always heard that the 292 was a better motor (newer & more main bearings & higher RPM). It couldn't just be the extra 10 cubes. I'm just looking for more bragging rights for my 302 so please fill me in.