The Stovebolt Site Forums The Shop Area Engine Shop Is 292 inline-6 up to the task OR is v8 a must?

Whew.. thankful for these forums. Is the 292 inline 6 worthy of 4wd or towing scenarios? OR is a v8 the only way to go.. Trying to keep original look and I like the inline-6. Also, does anyone have ANY clue of gas mileage scenarios when adding a 4wd axle to the front? Does the inline 6 do better or worse than v8? I will probably be going muncie 4 speed OR even nv4500.. 5 speed. With no load I have heard of folks getting nearly 20mpg.. I dont know how adding an axle to the front would change it that much if not engaged unless traction needed..

292's will actually out-torque some V8's. They were designed to replace the 261's in medium-duty trucks, where gas mileage was secondary to moving moderately heavy loads efficiently. Thar emphasis on low end torque makes a 292 a real gas hog, although an overdrive trans will help until you get hooked up to a trailer. Then running in direct drive 4th. gear will probably be needed unless you're on land as flat as a pool table. Making any of the 3rd.-generation sixes such as the 230, 250, and 292 fit into trucks from the 30's, 40's, and 50's is going to be a bit of a challenge, as such things as bellhousings, crossmembers, drivetrain, and motor mounts will all have to be modified, or swapped out for later model parts. The 292 water pump and fan might not line up well with your radiator without some creative tinkering, and the original "zero-pressure" radiator will probably have to be recored for one that can handle modern cooling system pressure- - -ditto for the heater core. 4WD doesn't win any gas mileage awards, even if it's not engaged frequently- - - -even with the hubs unlocked, it's usually good for a 2-3 MPG loss over a similar 2WD vehicle. Most of the 292-equipped trucks I've worked with struggled to get 12-13 MPG.
Jerry

FWD gas mileage: remove the front driveshaft

I know I will get repercussions from this post but. Most of us are gear crunchers but have you thought of putting on an automatic with one of the many after market high quality torque converter kits. You can then get six speeds and pending on a high gear, after tranny secondary converter you can have a 7th highway gear which drops the rpm. Doc.

The 292 should be up to the task, but if you swap one in and decide it’s not, you can always turbo it!!

https://spaturbousa.com/products/t4...olet-250-292-inline-6-i6-engines-tmc05t4

After thought: A big six would not only look great under the hood but, EVERYTHING is so easy to get to and you have plenty of room to add A/C, oil coolers etc.. A big plus for me is installing a A/C heater combination from a 2016 Lexus. NO water hoses required for heat, it's all electric. You will have to have 12 volt system unless you use a split system. My 54 has two large deep charge 6 volt batteries. One six volt runs all the lights and 6 volt generator charges both batteries but runs the 12 volt a/c, heater. I still use my six volt starter which is a high amp armature and field coils but it only takes about two seconds to start engine. I always keep a 12 volt starter in the parts room. So much you can do, Hotrod Lincoln and Tc to mention a few are a wealth of knowledge. They have forgot more than I will ever know. Doc.

Problems with big, long stroke engines run with original gearing are cam timing, internal friction and pumping losses at high vacuum.

A big engine running at high vacuum loses a lot just trying to suck air past the throttle blades. In my experience a 454 V8 gets 12 on a good day in a 3/4-ton pickup. A 350 in a similar truck will get maybe 15. That's a 25% improvement. But put a big trailer behind it and the 454 will get 8.5 plus while the 350 will get about 8. Under full load the pumping losses fall to near zero.

So what else is going on? There's cam timing. An engine whose torque peak is 2,000 RPM running at 3,000 rpm will be a gas hog no matter what else you do. My 235 want from sub 10 mpg to almost 13 mpg with a change of camshaft to one with a torque peak of 2800 RPM; no other changes. I had similar results with a motorcycle engine.

Then there is the issue of internal friction, and inertial losses from reversing piston direction twice every revolution both associated with long-stroke engines. Compared to say a 283 V8 a 292 is a very long stroke engine. It was designed to run in the range of 2,000 RPM give or take a bit. The small-block was designed to produce more power in a compact, light-weight package and will run happily at 3,000 RPM. My 235 running on flat ground at 2000 RPM has oil temperature about the same as coolant temperature. At 3,000RPM on the same day and road the oil temperature climbs to 275 deg after a while. Coolant temperature remained the same. Where did the extra heat come from? Burning gasoline.

So if one wants a flexible, fuel efficient engine, it should run at about it's torque peak at cruise speed, it should be as close to zero vacuum as practical, it should have minimal piston speed and greatly reduced internal friction. That's not a 292 I-6 running at 3,000 RPM on the interstate. Sounds like a turbocharged 4 cylinder with direct injection and a 10-speed automatic transmission. Well how about a compromise and a 305 Vortec V8.

Assuming inertial mass removed for simplicity, the 3,000 RPM X 3.00" stroke is 63.8% higher than 2,000 RPM X 4.12" stroke. It varies inverse to the square of the RPM.

Doc, I’d love to know more about that 2016 Lexus 12v heat and AC!!

Wow.. great experience here. Thanks all. Wonder if going 5 speed and keeping the revs @ about 2k on the bway would make the case for the in-liner 292.. hmm thinking what rear gear that would equate to.. maybe a 4.10-4.56. .or 4-speed 3:23 :o

side note: I guess in that case a 302/305 with TQ peak @3200 could even work.. now that would probably be more like ?.?? gearing with a 5 speed or maybe 4:56 with a 4 speed..

There is a great bunch of online gear calculators over at www.4lo.com