thanks alot old buzzard. that will come in real handy. the other motor is supposed to be a later model. it has the gmc on the valve cover with the m underlining the g and the c . i'll desypher those numbers tommorow. thank you also rich fox. hell, thank you all !!!
That flywheel is a recessed unit from a big truck - your pressure plate was likely a 3-finger unit as well. You can get them apart with a little patience - removal of the throwout bearing and release fork makes life much easier. You won't want to use the bellhousing that came with that motor either - get one from a chevy - they are the same part as the GMC small truck bellhousing. If you want a column shift, you will need one with the pivot shaft installed. As for the 59 with dual headlights - that is a rare bird "Fleet Option" truck - get some photos and post at oldgmctrucks.com
Not really traditional, but a very clean build is this GMC with a Whipple blower on it from up here in Canada.
what is this fleet option ? i thought all chevys and gmc's had 4 headlights starting in 58. the plans are to get an adaptor and use an automatic.
If you were buying new GMC trucks just because you needed them for trucking purposes and you weren't concerned with style, you could save some money by buying the "fleet" models with single headlights on each side, as well as a grille that consisted of a rolled piece of wire mesh.
So is it a 302 head you are looking for or the much harder to find 270H head? As I answered I don't have either anymore. But they are different and use different pistons. I always used the 302 head.
this is engine no. 2. why does one have pop-top pistons and the other have a slight dish ? i would very much appreciate if some of you gmc guys could shed some light on what we have. both engines have the small port head.
The combustion chambers look the same? I remember pop ups on my 270. Obviously the flat top engine is later as it has the 6 bolt crank. These are both 270s right? Measured bore and stroke.
The"flying M" emblem on the valve cover in the oval I believe is pre 1948. The other one is post 1948. Are you sure thase are 270" engines? 228 at least one the early one is much more common. I sure you can find deffinate information on the Inliners Internationsl site.
The number stamped next to the distributer hold down is the quick and easy way to see what engine it is.
yep rich, that no. by the distributor, the first 3 numbers on both engines start with 270. on the one with the pop tops, the combustion chamber is a lot deeper. i havnt measured the stroke.the bore on both engines looks like 3 and 25 thirty seconds.the pop-top engine has this on the side.i know you can't read it, but it tells the no. of cylinders and bore and stroke.
bearing burner. this is whats on the pop-top engine. this engine has an oil filter system and stamped on the lid it says:MILITARY STANDARD FILTER.
Looks like the pop up engine is a WW2 deuce and a half engine. Pretty cool. The other seems to be a later civilian engine. Just difference in manufacturing ideas over the years, I guess.
What are your cylinder head casting numbers for each engine? They will either be on the top of the head just above the ports, or beneath the valve covers depending on which head you have. I'm in a similar boat, as I bought two 270's recently. One is an older model (1946-1954) with the old script valve cover, and the other is a later model (July 7, 1958 according to the date code on the block), which has the newer GMC logo on the valve cover. My block casting numbers are the same as yours (2135412 for the older block and 2324003 for the later block). The odd thing on my older engine is that the head appears to be a 228 head (casting #6107412). I haven't pulled this head yet, so I don't know if it has the pop-up pistons. My later block has the common late small-port head (casting #2194819) with flat top pistons.
the pop-top piston head is 2136477 and the flat -top engine doesnt have any casting numbers on the head.i found whats left of a decal right above the generator on the flat-top engine that has R-M engines, or at least that what it looks like. could this one be a remanufactured engine ? the port size on both are 1.375. good luck with your project quick silver. thanks again rich fox.
love those GMC 6's, the Vs and the straits. here's a good gmc site for ya. http://www.6066gmcguy.org/ im always a fan of the inline 6. i just got a international 401 inline 6 cyl to work on, no clue yet as to what im putting it in.. but it's a big bitch
It sounds like you probably have the "819" head on the later engine. The casting number is inside of the valve cover next to the pushrod holes between cylinders 4 and 5.
I have a 270 right now being rebuilt. for good parts to get for them go to http://www.cliffordperformance.net/.
When I built my 270 I got the flywheel, pistons, cam and lifters from Jack Clifford. Chuck Potvin was grinding cams at Dean Moons then and still had some GMC blanks. All those guys are long gone now. My 270 still has an El Mirage record. Those old guys knew a couple of things.
I just looked there and saw a header and a couple of single 4 bbl manifolds for 270s. Go back and click Chevy 235 and then you can get to some expensive GMC parts.
I have a line on a GMC 302 short block, that is still in the factory crate. I can come up with most of the missing parts, oil pan, head, etc. However, the harmonic balancer is a problem. I already have a balancer off of a 235 Chevy. It is from a 1960 factory power steering car, so it has the bolt on crankshaft pully. Will this work on a GMC six? Also, will rocker arms and shafts from a 1956 270 GMC work on a 302? Thanks, John.
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