Projects 1954 GMC Series 1

I see the cam bearings but, sadly no rod bearings. But im having to look at 1956 to get the 270 option

 

More Information for SEALED POWER 1905CP (rockauto.com)

 

270 and 302 have the same stroke. Not sure on balance weights for the counterweights. 302 was larger bore, same stroke as 270. That's why 302 is unique block only used for 302. One of the more GMC experts csn verify if 302 crank can be used in 270 without balance issues. But if you end up with overbore new pistons, you'll likely want to balance the rotating assembly anyway.

 

GMC 6 cranks are all balanced as is with no material clamped on to simulate rods/piston/rings. Therefore any crank will bolt or fit in any block with no modifications that I know of.
I always have my cranks balanced when turned and balance everything else on my own with a 3 beam scale and some connecting rod fixtures I’ve made. All the custom pistons I’ve had made in the last 45 years have been within 1/4 gram and not surprisingly rods from an original engine were perfect; but rods can be way different engine to engine.

 

Thanks guys so far Rock Auto seems to have everything but oversized pistons and rings. Egge seems to be able to make them, BUT id not gain anything with their domed pistons apparently with the small port head.

 

Well after countless emails and calls, sadly i think i am giving up on the 270. 248 is just as bad. So now i have a pile of parts that ate seemingly worthless. Ill be putting together a list of parts for sale soon, including the T5 thats almost ready to bolt in and the intake and exhaust manifolds and anything else.
Question is what do i want to put in it….


Also considering selling the entire lot, as a project and put it toward something that runs and drives.

“Toyed” with the thought of building a Turbo 22R. Lol probably be shown the door if i did. Lol. Know the motor more than any out there and know many tricks to get some decent HP out of one.

 

Find a cheaper 6 to build
292 Chevy would be fun

 

Hell it’s a GM product.. . . . I’d put in a Ford 300 6….they are way better than a GM 292.. Check them out on You Tube.

 

Gotta love a 300 ford 6. My work van had one and it took serious abuse and lack of maintenance (not my fault, boss said 10k oil changes) till it sent a rod thru the block and across the parking lot. Lol flipping great motors.

 

The 300 Ford is the greatest light duty gasoline truck engine ever built. Period. Hands Down. I wouldn’t think twice about putting a 300 into anything.

 

I wonder if the T5 would take the torque from the 300. But talk about a way to really tee off a GMC Purist. Got my gears turning. Need to find measurements, figure motor mounts etc. lol

 

Look for an M5OD. They were used from 1987 to 1996 in millions of F-150’s.

 

Small block ford bell housing bolt pattern on the 300s
Lots of transmission options

 

Just got here & haven't read all yet. The 300 Ford would be an interesting swap. They are great engines. The later one were injected but don't say that loudly here. I'm sorta partial the the GM sixes because that is what I know.

OK, Caught up but I gotta' sleep on this.

 

Found a 302 locally in a local guys workshop friend of a friend. Wants a bit of coin ($1k) for it but it’s supposed to be a rebuilt motor. Came out of a bus. Been in the guys shop a long while, but he said he put oil in all the jugs before it was stored. Hopefully go look tomorrow.

 

Chevy 4.8 and 5.3 pistons @ 30 overs is 3.81 bore. But a smaller wrist pin. Cant sleep so im staring at bore and stroke charts. If the 302 falls thru i might have to franken engine the 270.

 

If it is what’s told… today that’s a very good price. It probably has the 10 qt deeper pan which is fine if it clears everything. Any of the other pans fit fine but will need the bottom of the oil pump and floating pick up.
If you take the pan off this is the time to tap the front main cap so you won’t have bolts and nuts on the bottom of the timing cover.

 

Definately a good price, last one I found locally was 3K

 

Keep in mind wrist pin location as well.

 

If ya did decide to look at a 230-292 Chevy 6 you can use a 72 down truck bell
Should bolt up in place of the original gmc

 

I didn’t know the trucks had the side mounts on the bellhousings to sit on the crossmember.

 

this one came from a 64 c10 with a 230/250.
I think this style made it to the early 70s

 

That is the same bellhousing I have for our 230/SM326 swap into our 1950 3100. Are the GMC bellhousing crossmembers and Chevy bellhousing crossmembers similar?

 

I think so. Both the frames I have are GMC
My 1949 gmc had a 59 235 and 64 ish Saginaw 3 speed

 

That is great news, thank you Anthony!!

 

Attended a car show yesterday showing the F1 I posted earlier at our local American Legion show part of our towns Blast from the Past weekend. Horny Mike and Ryan from Counts Customs were our Honorary Guests. During the show i got to chat with Ryan and found he’s got a 54 sitting on the side of his house he’s going to build when their busy show/tour stuff settles down. And was excited as hell I am trying to keep it a Six, he wants to do the same for the same reason.

After the show, I get a call from a good friend and fellow car guy, Get over here! The guys are hanging out. So i got to hang out and chill with Mike and Ryan for a few hours with a small group of guys. Both of them are super chill and down to earth. Got a couple pics of them with me, had a few drinks, had good food before they we ready to head to their hotel for the night to catch their early flight back to Vegas this morning.

 

Cool! I took my '53 to our club's annual show, Northern Nevada Inliners. Over 100 cars about half of them inline engines mostly sixes, some fours and a couple of eights. Some show quality, some like mine., most in between. The only trophy we give is for the "Rappin' Contest" that unique inline sound. This year won by a '53 Buick 8 in a 20s Buick speedster.

 

Dumb question. Taking a few more measurements of the pistons, I noticed something ive never seen before (other than the rings not installed in the right order) (inside bevel ring is fitted to #3 groove) but in the top ring groove, at the top, there appears to be a shim in every top groove.

 

I don't recall that either. Are these the pistons the last "rebuilder" set up?