Pondering the American inline sixes

[Flivver250]

The final generations of the Ford 300 and the GM 250 were good engines, but both were phased out years before the Jeep's 4.0. The GM 292 was torquey, but not really very common. The slant six never made any power to speak of and is dead and gone. All of the sixes had stout ancestors, but they rarely made above 155 hp in the stock configuration. I think the Ford was in the 250 ft lbs of torque range, the 292 about 280 ft lbs of torque. All in all, factoring long block weight, torque and horsepower, the fuel injected 4.0 may well have been the best inline stock inline six ever made in America. All of the brands boasted reliability and longevity, the Jeep stayed in the production game the longest and is still a common sight on the road. I almost never see the 225, 250, 292 or 300's as daily drivers anymore. Something to think about.

 

[Goatman]

Jeep, especially under AMC used most every other US auto company's parts on their products to save costs. They spent (probably) more money cobbling together various parts than on actual engineering new parts themselves. One of the main reason for AMC to buy Jeep was to acquire the 258 engine. Ford Bronco, Chevy Blazer both went full size and required more than an I6 could deliver. And emissions on a I6 is much more difficult than on a V6. And the smaller V6 offered easier packaging for better aerodynamics and fuel milage. AMC was gasping for air so spending millions to develop new drivetrains was out of the question. Mercedes got Jeep and needed to put something in the showrooms so the I6 soldiered on even longer until they could redesign the vehicles. Their updated Wrangler was to be what followed the TJ. But they were bleeding cash to try and turn Dodge Chrysler profitable. The JK was their baby. But then sold to Fiat. Who did the JK refresh with the better 3.6 V6 and somehow reaped the rewards of Mercedes R&D into the pickup and 4wd segment. The Fiat fresh Wrangler became the JL and the rest is history. I thought the French would finally destroy what was left of the Jeep division, but it looks like the French finally won a battle on their own.
-Very very brief overview-

 

[K0LCB]

I believe the best inline 6 I ever had was the Cummins 5.9

 

[Fouledplugs]

I believe the best inline 6 I ever had was the Cummins 5.9

Two different worlds and cant compare. But I believe the OP was talking strictly gasoline engines.

 

[Flivver250]

Two different worlds and cant compare. But I believe the OP was talking strictly gasoline engines.

Yes, gas engines. I have seen factory 5 cylinder diesels in Jeeps, a Mexican built Cherokee and the old military aircraft tugs which may have been a CJ. I am not really biased towards Jeep. I have owned a couple of the GM 250's, good engines with minor correctable flaws like the distributor and intake/exhaust manifolds. I think they retired that engine while it was still sporting a carburetor. I never did own a Ford 300, but they were often the farmer's first choice. The trucks died long before the engines. I worked on many a slant six. Reliable old slabs of iron. Gutless and indomitable. Just replace the starter and alternator every time you change the oil and you shouldn't have a problem. They are also good for the prevention of speeding tickets. I doubt I have seen more than 3 or 4 292's in my entire life.

 

[pagrey]

The Ford 300 is overall a better engine than the 4.0, I like my engine and my Jeep but it just isn't the Ford as far as a solid reliable engine. Ever seen a UPS truck? Those things go miles with nothing but oil. While the 4.0 is used in light trucks the 300 was put in heavy equipment, generators, light trucks, everything.

I think a good way to put it is the 4.0 is considered one of the best *off-road* engines of all time and the 300 is considered one of the best engines of all time.

 

[JEEPCJTJ]

One of the main reason for AMC to buy Jeep was to acquire the 258 engine.

Most of what you posted is pretty much correct but not that.

The AMC 258 started out in 1971. It was the same engine as the 199 and the 232 which both started in the mid 1960s. The bore and stroke and/or the connecting rod length depending on which engine and when, were the only differences.

Kaiser Jeep was sold to AMC in 1970 and AMC built the last year of Kaiser Jeep designed CJ5s in 1971. For 1972 AMC used a longer frame, front fenders and hood so they could fit their 258 or 232 instead of the Dauntless V6 which was made from the engineering and tooling Kaiser had bought from Buick. AMC ended up owning it but preferred their straight sixes and sold the whole V6 thing back to GM in 1974.

 

[JEEPCJTJ]

The slant six wasn't very powerful but for some reason there were quite a few performance modifications available back then. The best thing about that engine was that it was hard to kill. I know a girl that drove her's to work and back with no oil for two weeks before it died. Actually it didn't even die, but did need replaced. I couldn't believe the banging noise when she drove up my mom's driveway when she wanted it fixed.

 

[billiebob]

The Ford 300 was a great engine my F250 had over 400K miles on it.

The Ford family of straight sixes were all fabulous. I had the 170 in an Econoline pickup. My Moms Falcon had the 200. And there was also a 250. The seond Mustang bult was a convertible with the 170" six.

 

[Flivver250]

A small and useless factoid. Chevy never had a flathead engine. I think every other US auto manufacturer did.

 

[mots]

What about the inline sixes in the Trailblazer etc. produced in Flint, MI?
4.2L - Vortec 4200 from the Atlas series of engines

https://www.topspeed.com/cars/car-n...-engine-gm-s-42-liter-atlas-i-6-ar174949.htmlhttps://jalopnik.com/one-of-the-last-american-inline-six-engines-was-in-your-1794604005
I'm not sure how reliable they are, but they did have a lot more power than our 4.0L and were a much more modern engine. "All engines in the Atlas family were built entirely of aluminum, and shared piston designs, connecting rods and a number of other components. They all had a 10:1 compression ratio, dual overhead camshafts, four valves per cylinder, electronically controlled throttle bodies, and infinitely variable exhaust cam timing. "

 

[Squatch]

Most of what you posted is pretty much correct but not that.

The AMC 258 started out in 1971. It was the same engine as the 199 and the 232 which both started in the mid 1960s. The bore and stroke and/or the connecting rod length depending on which engine and when, were the only differences.

Kaiser Jeep was sold to AMC in 1970 and AMC built the last year of Kaiser Jeep designed CJ5s in 1971. For 1972 AMC used a longer frame, front fenders and hood so they could fit their 258 or 232 instead of the Dauntless V6 which was made from the engineering and tooling Kaiser had bought from Buick. AMC ended up owning it but preferred their straight sixes and sold the whole V6 thing back to GM in 1974.

Thanks for posting that. I was about to do the same, but figured I'd better read all the posts before doing so. Glad someone else saw the error, too.

 

[Squatch]

The slant six wasn't very powerful but for some reason there were quite a few performance modifications available back then. The best thing about that engine was that it was hard to kill. I know a girl that drove her's to work and back with no oil for two weeks before it died. Actually it didn't even die, but did need replaced. I couldn't believe the banging noise when she drove up my mom's driveway when she wanted it fixed.

I've owned and driven at least half a dozen of Chrysler's slant sixes. It was nothing to get 250,000 miles out of one. And you're right, they were no powerhouse. However, did you know they had a performance version available in the early 60's? It was called the Hyper Pak. Below is what Wikipedia had to say about it:

Hyper Pak

Reproduction Hyper-Pak intake on a slant-Six engine

The Hyper Pak was a parts package made available from 1960 through 1962 at Chrysler Corporation dealer parts counters. The parts were made available to comply with the regulations of sanctioning bodies for racing events in which Valiants had been entered by factory-backed teams: All parts used had to be "stock" parts, the definition of which meant that they were available through normal factory parts channels. The Hyper Pak consisted of a very-long-ram intake manifold meant to accept a AFB 4-barrel Carter Carburetor, the AFB carburetor itself and an appropriate air cleaner, dual (front-3 and rear-3) cast-iron exhaust headers, a large-diameter exhaust Y-pipe to connect to these dual cast-iron headers, a larger muffler, a 276°-duration camshaft with appropriate valve springs and pushrods, a heavier-duty clutch, a manual choke control, a starter motor modification template and, in the full-race version of the package, high-compression pistons designed to increase the engine's compression ratio to 10.5 from the stock 8.5. The Hyper Pak was recommended for installation only on vehicles equipped with manual transmissions, for the camshaft was of such characteristics that a high idle speed was required to prevent engine stall-out. The Hyper Pak was primarily intended for competition driving, its road manners involving rough idling and poor cold-engine driveability, a high power band and poor fuel economy. In competition events it proved unbeatable. Eight factory-backed Valiants entered the 1960 NASCAR compact car race at Daytona Beach, and humbled the competition. The Valiants came in first through eighth. After a similar performance the following year, the race was dropped. A high-fidelity reproduction of the Hyper Pak intake manifold was created by Slant-6 builder Doug Dutra in the late 1990s. Subsequently the tooling was sold to a marketer of performance equipment for inline six-cylinder engines.


I guess they also had an aluminum block version of the slant six, which I can't say I ever knew of. I do know, however, that while most folks think of the slant six as only a 225 cid, they had the 170 and 198 sizes, as well. I owned a 170 for a while.

 

[Squatch]

Rambler/AMC had three inline six cylinders prior to the release of the '64 232 cid in the Typhoon (the 232 actually predated the 199). The three engines were all the same displacement, that being a 196 (195.6, actually). How did they have three of the same displacement? They had a flathead, a cast iron OHV, and an aluminum block OHV, all being sold at the same time! The aluminum block was short-lived, only being produced from '61-'64. I have two of the '61's in my garage, currently. Besides being aluminum, the other major difference was that the oil filter was mounted down off the oil pump, instead of being mounted upside down up by the front of the valve cover, like on the other two variations. I've owned and driven a number of the 196 OHV engines. Good ol' engines...

 

[Sancho]

I like threads like this.

Thanks for posting. Gimme more.

 

[Flivver250]

In high school I had a 1962 Studebaker Lark with a 170 straight six with an automatic. Cool car but not a racer. It was my second car. Bought it in flawless condition for $25 bucks.

Rambler/AMC had three inline six cylinders prior to the release of the '64 232 cid in the Typhoon (the 232 actually predated the 199). The three engines were all the same displacement, that being a 196 (195.6, actually). How did they have three of the same displacement? They had a flathead, a cast iron OHV, and an aluminum block OHV, all being sold at the same time! The aluminum block was short-lived, only being produced from '61-'64. I have two of the '61's in my garage, currently. Besides being aluminum, the other major difference was that the oil filter was mounted down off the oil pump, instead of being mounted upside down up by the front of the valve cover, like on the other two variations. I've owned and driven a number of the 196 OHV engines. Good ol' engines...

I always thought highly of the 232.

 

[Flivver250]

My neighbor had a Marlin with the 232 three on the tree. He wanted $75 for it. My parents wouldn't let me buy it. As I recall the front seat folded down level with the rear, the main tactical attraction it had for me. The fastback Marlin was actually a sharp rig.

 

[Squatch]

My neighbor had a Marlin with the 232 three on the tree. He wanted $75 for it. My parents wouldn't let me buy it. As I recall the front seat folded down level with the rear, the main tactical attraction it had for me. The fastback Marlin was actually a sharp rig.

I have a '66 Marlin project in my garage. It's a 327 V8 4bbl car. I've owned four or five of 'em. I've always thought the lines were beautiful, myself. And yes, the seats fold down flat-ish (flat enough!). That option went all the way back into the 40's, as I recall.

 

[Flivver250]

I have a '66 Marlin project in my garage. It's a 327 V8 4bbl car. I've owned four or five of 'em. I've always thought the lines were beautiful, myself. And yes, the seats fold down flat-ish (flat enough!). That option went all the way back into the 40's, as I recall.

I had great aspirations of staining those seats. I think the Marlin was a beautiful car.

 

[Goatman]

Most of what you posted is pretty much correct but not that.

The AMC 258 started out in 1971. It was the same engine as the 199 and the 232 which both started in the mid 1960s. The bore and stroke and/or the connecting rod length depending on which engine and when, were the only differences.

Kaiser Jeep was sold to AMC in 1970 and AMC built the last year of Kaiser Jeep designed CJ5s in 1971. For 1972 AMC used a longer frame, front fenders and hood so they could fit their 258 or 232 instead of the Dauntless V6 which was made from the engineering and tooling Kaiser had bought from Buick. AMC ended up owning it but preferred their straight sixes and sold the whole V6 thing back to GM in 1974.

You are absolutely right. Fingers thinking faster than my brain.(surprise! ) Thanks for the correction.