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[Savidio44]

Thinking of buying a '69 C-10 with 292 and 3 speed manual. Will look at it Saturday, but from the photos looks like I might end up bringing it home with me. Biggest question in my head is whether I should consider the swap to a V-8 as part of the future expense of this truck? It will end up being a weekend driver vehicle, maybe haul a load of mulch once in awhile, but no heavy lifting or no towing. Are 6 cylinders vastly undervalued? If I buy it and fix it up will there be enough demand that I can get rid of it at some point? My guess is that with a cam, headers and new intake & 4 barrel I can make as much horsepower as a stock small block without too much $$. Do you guys recommend this or not? If I buy it should I convert it to a V-8? Let me know please.

[Grumpy old man]

I think you should swap it out and put a nice 350 in there and put me first in line for when your ready to sell that junky under powered 292 !

[PanelDeland]

The 6's in these trucks are great engines for a workhorse.Unless you just have tons of cash laying around,the 350 is the way to go for performance.The performance parts for a 6 are way higher than V8 parts.If you just want a good running reliable truck to use around he house and cruise,the 6 works fine.For performance,you can probably swap in a 350 for less than you can add a cam,headers and intake to the 6.
If different is your thing,there's a good thread on 6 cyl.

http://67-72chevytrucks.com/vboard/s...d.php?t=405814

[BigCountryx]

I've got a 250 and it pulls itself around very good. I drive it daily since I've swapped out the ignition. I can only imagine the 292 is even better. I really intended to keep it a 6 until I ran across a deal I couldn't pass up on a 5.3.

[Carl Spangler]

Originally Posted by Savidio44

Thinking of buying a '69 C-10 with 292 and 3 speed manual. Will look at it Saturday, but from the photos looks like I might end up bringing it home with me. Biggest question in my head is whether I should consider the swap to a V-8 as part of the future expense of this truck? It will end up being a weekend driver vehicle, maybe haul a load of mulch once in awhile, but no heavy lifting or no towing. Are 6 cylinders vastly undervalued? If I buy it and fix it up will there be enough demand that I can get rid of it at some point? My guess is that with a cam, headers and new intake & 4 barrel I can make as much horsepower as a stock small block without too much $$. Do you guys recommend this or not? If I buy it should I convert it to a V-8? Let me know please.

I'd recommend using the truck for a good 6 months before deciding on something that drastic. If the C10 is a short bed there's less weight to haul around and a 6 may be OK for you.

I have the 250 in my SWB and it's adequate for my needs. Gets very good fuel mileage compared to my previous C10 with a 350.

cheers
JohnG

[DirtyLarry]

I personally wouldn’t swap a V8 in place of an I6. I6 trucks are getting pretty rare after 4 decades of people pimping them out. Everybody has their own opinion but to me a bone stock truck with a straight 6 is more valuable than one that has been molested with a V8 swap. I would love to find a ’68 C10 with a 292 or ’68 GMC with a 305 V6 just because they would be rare into today’s Gen III swaperoo world.

[19673ontree]

I love the 250 and 292 6 cylinder engines they are awesome ! Ive owned several of them and they are super dependable , I even rebuilt one back in the 80's , I drive my 67 c10 a lot april thru october it has a 250 I added power steering and air conditioning to it mine drips oil out the rear main seal iv'e been thinking about rebuilding it for the last 5 or 6 year's and I may at some point take it out and rebuild it , had to put a new set of point's in it last year , may put plug's in it this spring the upkeep on these is probly $20 or $30 dollar's a year , so if you want a good ole truck to drive and enjoy the 6 cylinder will do the job ,

[72freak]

Drive it until it "really breaks". During that time decide if the power of the engine and the originality of the vehicle is that important to you. The amount of money you will spend rebuilding it will be about the same as doing a a V8.Also if its a keeper or a flipper. Once you get through all that proceed. If the engine is doing well but you decide you really want a V8 start buying the parts you need to do the swap while its running. That way it will only be down for a short time. Now if you are going to put a V8 in it and it being a 3 speed, I think you will have to keep the engine in the stock I6 location crowding the fire wall and leaving an unsightly gap at the radiator. If it was an automatic you could just lengthen the drive shaft and move everything into the V8 holes and it would look correct. (I may be wrong on not being able to move the 3 speed, x member, trans and linkage forward)

Its basically a personal preference.

[Malamute]

I have an l6 250 w/ 3 OOT and I have a '69 w/ SB 400 w/ 700r4. One hauls ass, chugs gas but is fun as hell to drive. The other just gets me from point A to point B but has a lot more people gawking as I get there.

I'd keep it in and leave the v8 out.

[factorystock]

If the 292 is a good runner, leave it alone. Most v8s don't put out high torque at low rpms. 6's are easier engines to maintain, spark plugs and distributor are very accessible.

[hotrod68c10]

if u do decide to go 350 it will bolt right up to the 3 speed same flywheel everything butt early model high nickel blocks are getting harder and harder to come by unless u wanna pay big bucks 4 crate I would start searching for good seasoned block

[hotrod68c10]

Originally Posted by factorystock

If the 292 is a good runner, leave it alone. Most v8s don't put out high torque at low rpms. 6's are easier engines to maintain, spark plugs and distributor are very accessible.

agreed on good runner if well maintained

[54blackhornet]

My 68 GMC is bone stock except a 292 sits in place of the original 250. It gets a lot of attention when I open the hood....

[67_C-30]

The 2 trucks I've had with 292's ran great and pulled good, but sucked on gas. I tuned both of them up, changed to HEI in one of them, and rebuilt the carbs on both, but they still would not get much over 10 - 12 MPG. Now the 250 in my '68 C-10 gets around 14 - 16 MPG since I've rebuilt the crab, put a new vacuum advance, and points in it, but lacks the torque the 292's had. My 250 with 3.73's and 3OTT gets around the same fuel mileage I've typical got with a fresh, stockish 350's with a tuned Q-jet, TH350 trans and 3.08's, but it has way less power. I don't mind the 250 in my truck now, but I'm going to eventually change it out to a 350 with a fresh Q-jet and a NP-833 4 speed OD trans. I thunk it will get better fuel mileage than my TH350 trucks, and definitely be more fun to drive than a crappy automatic! -lol

[hotrod68c10]

Originally Posted by 67_C-30

The 2 trucks I've had with 292's ran great and pulled good, but sucked on gas. I tuned both of them up, changed to HEI in one of them, and rebuilt the carbs on both, but they still would not get much over 10 - 12 MPG. Now the 250 in my '68 C-10 gets around 14 - 16 MPG since I've rebuilt the crab, put a new vacuum advance, and points in it, but lacks the torque the 292's had. My 250 with 3.73's and 3OTT gets around the same fuel mileage I've typical got with a fresh, stockish 350's with a tuned Q-jet, TH350 trans and 3.08's, but it has way less power. I don't mind the 250 in my truck now, but I'm going to eventually change it out to a 350 with a fresh Q-jet and a NP-833 4 speed OD trans. I thunk it will get better fuel mileage than my TH350 trucks, and definitely be more fun to drive than a crappy automatic! -lol

amen on crappy automatics

['68OrangeSunshine]

292s are less common than some other GM engines. A parts guy at the Chevy dealers' once told me ''the 292 was GM's best kept secret.'' I think it's a fine engine. Certainly idiot proof, as I have been driving behind one or another for 40 years.
Hot rodding is do-able but expensive. Torque like a Big Block. The advantage is the surprising longevity of the Chevy L6. I got 25 years and 250,000 miles out of my 1977 build.
The 292 that we got on the road in 2005 is just breaking in. I have a crate 350 in a '71 GMC Jimmy, but it has nowhere near the guts that my simple '68 Stepside C/10 w/292 has.
The next two cores I will rebuild will be 292s.

[RichardJ]

For that truck, I would worry less about the 292 than I would the 3 speed and the rear gears. I don't know what gears they originally put in a 1/2 ton behind a 292. My 3/4, C20 with 292 had a 3 spd and 4.56 gears. It could pull a battleship out of the water, but couldn't beat a Vespa across an intersection. Replacing the 3 spd with a truck 4 spd, made a marginal improvement. I allowed it to get a heavy load moving easier.

Replacing the 4.56 gears with 3.54 gears was a night/day improvement. It lost very little in towing capacity, but now effortlessly runs down the road at 75 with all the v8 boys.

I last checked the gas mileage in Oct on an out of town, day trip. Running 70-75 most of the way, it got 15.3 mpg. For an old 3/4 ton truck with carb, I'm happy with that.

['68OrangeSunshine]

Originally Posted by RichardJ

For that truck, I would worry less about the 292 than I would the 3 speed and the rear gears. I don't know what gears they originally put in a 1/2 ton behind a 292....

My '68 C/10 was originally optioned w/ a 292 L6, SM465 and 3.73 rear end. It's pretty lively.
Although I don't brag about my mileage, since I have a 260H Crane Cam, a .030 overbore, oversize intake valves [1.84"], Pertonix ignition, Offy intake, Eddy 500 CFM carb and Clifford headers. [And a lead foot.]

[70 shorty]

I love the hot rodded 250 in my c10. I would not swap it for a V8, for the simple reason that it's different. For the last couple of weeks, it's been serving as my daily driver, so i've been picking at getting it running better while my regular everyday driver is having problems. The last I checked, years ago, I was getting about 10 mpg in the truck though. It's a fairly modified engine though (see my signature)

[RichardJ]

OK, you're right, I shouldn't be bragging about that 15 mpg. That was a one shot deal, straight out the freeway to Palm Springs and back with unusually light traffic. Normal or average mileage is hard for me to get, because the truck is driven on such an irregular basis with mostly short, local trips. Todays 10% Ethanol evaporates so rapidly on a pre-charcoal canister, open fuel system on a vehicle that sits for days on end. On average I'm still able (I think) to calculate a low 14 number for local driving. Definately nothing to brag about, but as I said, I'm happy with it.

My intention was to let savidio44 know that the 292 mileage, while not great, can be lived with.

My 292 has .060" LPG pistons (9:1 C.R.), 1.94" IN valves, Crane roller rockers, Clifford intake, Carter AVS 4BBL (600 cfm). Hedman Headers, HEI and a only slightly bigger than stock cam. Stock is 188 IN/188 EX @ .050". Mine is 194/204 @ .050", while the Crane 260 is 204/216 @ .050".

I might add that the AC is a Climate Control and runs full time. Temperatures today are in the low 70's here in SoCal. Palm Springs temperatures in Oct are in the 90's.

[sambudo]

Originally Posted by Savidio44

Thinking of buying a '69 C-10 with 292 and 3 speed manual. Will look at it Saturday, but from the photos looks like I might end up bringing it home with me. Biggest question in my head is whether I should consider the swap to a V-8 as part of the future expense of this truck? It will end up being a weekend driver vehicle, maybe haul a load of mulch once in awhile, but no heavy lifting or no towing. Are 6 cylinders vastly undervalued? If I buy it and fix it up will there be enough demand that I can get rid of it at some point? My guess is that with a cam, headers and new intake & 4 barrel I can make as much horsepower as a stock small block without too much $$. Do you guys recommend this or not? If I buy it should I convert it to a V-8? Let me know please.

Keep the 292 3spd. I love the straight six, I like the stock look. But also enjoy the rat rod options on the i6.

['68OrangeSunshine]

Richard you have a very interesting set up. I don't see a conventional heater core.
1] Do you have carb heat plumbed to the Clifford intake?
2] Tell us about your air cleaner. It looks GM, but maybe from a C/60?
3] A real CARTER AVS is rare. The Edelbrock "AVS" <<Thunderer>> has only the 2-stage AFB-type jets and metering rods. The Carters had 3-stages. I have a core Carter AVS, [for a 440 Mopar] but I rescued it from being tossed out after being a movie prop. It was stripped out inside. Do you know where to get 3-step rods and jets?

I vaguely recall getting about 17 MPG in 1975 when the engine was much newer [< 85K] and I could feed it pure leaded gasoline. Also it was a mostly downhill run from Flagstaff to Tucson, and I used Neutral as much as possible.

With a .060 Bore = 301 cubic inches you are the Big Dog. There must be something to that roller-lifter magic.

[RichardJ]

The Lincoln Mark VII Climate Control unit used has the heater core and fan on the inside.

The earlier style Clifford has a machined pad on the bottom. I bolted a hogged out plate to the bottom and plumbed into that.

The air cleaner started out in life as the original 1 bbl, oil bath unit. I fabricated a larger 4 bbl throat, opened up the top crossover passage and gutted the inside to fit a paper element.

The Carter AVS is getting rare, but unfortunately everyone saves the 440 version with the larger primaries. The 383/340 versions with the smaller primaries are a much better street carb, even when used on the 440. The 3-step rods and jets haven't been available for years unless you find some used.
The 2-step rods and jets can be used in the AVS if you use the AFB or Edelbrock flat covers over the rods. The AVS has raised covers to allow for the longer rods.

The roller rockers were used simply in hopes of reducing valve guide wear from side loading, from the 1.75:1 rocker arms. When I rebuilt the engine about 7 years ago, I found more guide wear than I expected, because the head had been rebuilt around 1990 and hardened exhaust seats installed. It had excessive guide wear at that time. No indication of guide wear yet.

['68OrangeSunshine]

I know I had Stellite valves installed on the head of my last engine. I still have not pulled it apart for an "autopsy." It was acting sluggish after only 250,000 miles -- I had it put on an engine analyzer and the scope showed I had no action on the middle cylinders [3 + 4]. Just before that I had doctored up my Holley 390 with a 50cc accelerator pump. So I was getting around town on a big block 4 Cylinder, so to speak. We just turned to and started the build up of my spare 292 block.
I run a 12 x 3" circular Moroso air cleaner with a K&N unit. Actually I have the paper element in there now, since I seem to pass emissions easier without the K&N, and I've been too busy [lazy] to clean the K&N before putting it back on.
I do not run carb heat. Don't seem to need it in Tucson. It was 84* today. [I'm dreading what summer will bring.]
About 12 MPG is normal for me.

[Savidio44]

OK, it looks like you may have convinced me to keep the 6 banger. Something different for sure. Attached are some crummy phone photos of what I am starting with. Normal floor rust issues and bed floor rust, but it has been a Tennessee truck it's whole life. Could someone help me with how to convert a steel bed to wood? I think I may take that on. Thanks guys. This is a great site, I have really learned a lot since joining.