292 Information

[old51sedan]

Have access to a 292 to replace my 250 in my 1969 C-10. I know that the left side frame/motor mount will work. My question is about the right one. This 292 has the motor mount ( bolted to engine) and what is left of the frame mount. It was torched in half to remove from truck. He tells me it's the motor mount which is different, while I believe it's frame mount that I need to replace. Hope fully he's right, but I need to know. Also the exhaust manifold has three bolts for the exhaust pipe where the 250 only has two. Does this mean that the 292 has a larger diameter exhaust? I was thinking of using both the intake and exhaust manifolds from the 250 on the 292, but don't want to comprise the engine if it needs the larger size exhaust pipe. Anything else I need to know before I start this instillation would be helpful.

['68OrangeSunshine]

I don't know about the torched mount.
But the 3-stud exhaust manifold was used on heavy duty trucks. Light duty trucks w/292s had the same 2-stud manifold as the other L6s. So yes, your old exhaust is swap-able.

My '68 C/10 Stepside came stock with the 2-stud exhaust manifold.

That being said, a lot of hot rodders liked the higher flow of the 3-studded manifold.
It could be used with an Offy intake if you wanted a 4Bbl carb, or the stock cast iron intake could be mounted with a 2-into-1 adapter to use a small 2Bbl like the Weber.
Personally, I switched to an Offy intake, Clifford headers, and an Edelbrock 1404 Performer 500 CFM. But my 292 is no longer stock. It's got .030 over Badger cast pistons, Crane 260H cam, 1.84" intake valves, etc.

[Wrenchbender Ret]

The larger trucks, 1:1/2 ton up used a larger opening exhaust with straight down dump & 3 studs. The light duty later model 250-292 about 75 up, used a 3 bolt flange that was the same size pipe as the early 2 bolt flange. They had an angle dump. They are interchangeable by using a 3 bolt flange on the exhaust pipe.

[old51sedan]

Thanks for the reply, I believe I will use the 250 intake, manifold and carb on the 292. I man I bought this motor from had 6 of them and he had torched all of the frame brackets when he pulled them, what a shame. I guess now I need to look for one.

['68OrangeSunshine]

Do you have the top half of the 292 bracket? Maybe a welder could splice that to a lower part of the driverside bracket?
Be thankful you have a C/10. If you had a K/10 you'd also be hunting for the very rare 292-only diagonal under-engine crossmember.
I saw your post on the other stepside thread. Nice looking "51st Anniversary" paint scheme.

[E. Brower]

The PS engine perch is different from the DS -- I am looking for one as well -- Ask the guy who cut the old ones in half if he has the parts -- They could be welded back together -- If so I would love to have one -- Let me know -- Thanks in advance --

[VWNate1]

Those 292 mounts are out there and not $pendy if you take the time to search......

The three bolt exhaust manifold also doesn't normally have the heat riser flapper and spring .

A good thing to have for daily driver / work rigs in cold weather .

The '68 and later carbies are better for power , economy and all around driveabilty ~ available with automatic or manual chokes to suit your likes .

[Wrenchbender Ret]

Originally Posted by VWNate1

The three bolt exhaust manifold also doesn't normally have the heat riser flapper and spring .

A good thing to have for daily driver / work rigs in cold weather .

The '68 and later carbies are better for power , economy and all around driveabilty ~ available with automatic or manual chokes to suit your likes .

The 3 bolt exhaust outlet with the 2 in. pipe has the heatriser built into it.
I agree on the carb. The Monojet carb that came out in 68 was a better performing carb then the earlier model B.

[old51sedan]

This motor has been sitting in a barn for years along with all of the others. He had torched all of the mounts that way, the rest of the mounts were still on the trucks when taken to the boneyard. If I find more than one I'll let you know. How far from Hannibal is Pacific, I live there as a teenager.

[E. Brower]

Thanks for the info -- Am hearing that a V8 mount will work for the passenger side -- Im going to try it -- Will keep you posted -- The Han is 200 mi Due North of STL -- Had a girlfriend from Pacific when I was at MU -- E.

[VWNate1]

Originally Posted by Wrenchbender Ret

The 3 bolt exhaust outlet with the 2 in. pipe has the heatriser built into it.
I agree on the carb. The Monojet carb that came out in 68 was a better performing carb then the earlier model B.

Some do and some don't .

The good thing is : you can buy a brandy new Chinese one of decent quality that has both bolt patterns .

[old51sedan]

It is my understanding that the head will interchange between the 250 and the 292, is this correct? But does the 292 head have bigger valves than the one on the 250? IF so it wouldn't be smart would it to install a 250 head on a 292?

['68OrangeSunshine]

Originally Posted by old51sedan

It is my understanding that the head will interchange between the 250 and the 292, is this correct? But does the 292 head have bigger valves than the one on the 250? IF so it wouldn't be smart would it to install a 250 head on a 292?

I think when they were brand new the heads may have used different value springs, (possibly valves) but as the L6 type became more usual the 250 and 292 heads came to be the same thing.
A hotrodders trick was to increase compression by mounting a 230 head on a 250 or 292. [I actually have a 230 head on my 292, but it was rebuilt for a 292 with stellite valves and bigger 1.84" intake valves, but my 1.5" exhaust valves are stock diameter. I didn't know it wasn't a 292 head until I ran the numbers.] My 292 likes to run.
So answering in order:
1] Correct.
2] Not anymore.
3] Couldn't hurt.
If a professional machinist wants to correct my statements, I will not be offended.

[VWNate1]

That's an old time Hot Rod trick, works well too *if* you use a good grade of gasoline ~ regular pump gas can and usually will cause sub audible ping and this is death on any engine .

Finding a good machine shop that can and will install larger intake valves then smooth up and match port the exhaust ports (!ONLY!) whilst unshrouding the valves and guides, polishing the combustion chambers and matching them all CC wise ~ will provide you more tractable power out of even a 230 i6 than you can possibly imagine .

Engines are basically air pumps so tweaking them to breathe as well as any particular design allows , wakes them right up and doesn't cause shorter life .

Me, I tend to build them fairly low compression so I can work them really hard and the simply don't care ~ they keep on storming decade after decade .

[old51sedan]

Originally Posted by VWNate1

That's an old time Hot Rod trick, works well too *if* you use a good grade of gasoline ~ regular pump gas can and usually will cause sub audible ping and this is death on any engine .

Finding a good machine shop that can and will install larger intake valves then smooth up and match port the exhaust ports (!ONLY!) whilst unshrouding the valves and guides, polishing the combustion chambers and matching them all CC wise ~ will provide you more tractable power out of even a 230 i6 than you can possibly imagine .

Engines are basically air pumps so tweaking them to breathe as well as any particular design allows , wakes them right up and doesn't cause shorter life .

Me, I tend to build them fairly low compression so I can work them really hard and the simply don't care ~ they keep on storming decade after decade .

Thanks for the reply, I like these old inline sixes. This 292 had the water & oil drained out of it about 15 years ago. After removing side covers and tapper pan cover I poured 5 quarts of oil the engine. I pulled the dist. put a screw driver on the end of my drill and started spinning the oil pump. I only have two push rods that oil is coming up threw, should oil come from all of them? The lifters are pumping up after rolling engine over, may be a keeper. Also engine painted green, thinking it was an older one, but the pad by dist. is blank. I'm thinking this may have been a replacement block?

['68OrangeSunshine]

Green [Alpine Green close to Dupli-Color Detroit Diesel Green] was the MY '63 to '66(?) 292 only engine color. In '67 Chevy used Chevy Engine Orange for all engines, L6, SBC BBC.
All push rods should flow oil.
292s take 6 quarts with long [PF35] oil filter.

Some rebuilders may mill off the OEM GM dress codes. Usually they then stamp their own in house numbers. Try some CSI tricks like a UV flashlight to pick up faint numbers.
You can get date of casting by finding the casting numbers from the drivers side.
Keep us posted.

[VWNate1]

Nothing makes torque nor runs as smoothly as an InLine 6 Banger .

Unless you're addicted to noise and shredding tires a well tuned 6 Banger will get you where you need to go just as fast and more fun if you like to drive the twisty bits .

Keep us posted ~ it sounds like you're close to firing it up .

Static time to 10° BTDC then fine tune/time it once running and warmed up .
Try not to exceed 30° BTDC all in @ 3,000 RPM .

[Wrenchbender Ret]

The 292 had better valves with rotators on the exhaust. Even the older ones had hard seats. The head from the 196 gives higher compression.

[old51sedan]

Originally Posted by Wrenchbender Ret

The 292 had better valves with rotators on the exhaust. Even the older ones had hard seats. The head from the 196 gives higher compression.

Sounds as though I should use the 292 head. Even though at my age I don't need a hotrod, but I do want it to run good. I'm not going to do much more with it as I'm heading for warm weather in a week or so, but will decide in the spring as to rebuild it or fire her up to see how she runs. Thanks for the help

[VWNate1]

Originally Posted by Wrenchbender Ret

The 292 had better valves with rotators on the exhaust. Even the older ones had hard seats. The head from the 196 gives higher compression.

THANK YOU !.

I bought a stuck '66 292 for cheap and had the head all re done (new guides etc.) , the block was worthless needing re sleeving (free to anyone who wants a bare block) , the crank was previously turned to .030" and I decline to use thin cranks so it's stashed away for trading or who knows what .

The '66 292 head of course has no A.I.R. holes in it .

[E. Brower]

How did the motor mounts work out? -- I have tried using one from a 350 V8 on the passenger side -- It didnt line up -- Trying to find another one --