Best/Worst/Most Underrated Engines Ever Built?

[High-Test]

Best:

Mercedes-Benz M103 - can handle as much power as a 2JZ can, and it's all aluminum.
Ford Flathead V8 - Bombproof and sledgehammer simple. It was being built in Brazil through the 1980s.

Worst:
Mercedes-Benz M120. Hear me out on this one. For the first eight years of its existence, the thing was an absolute nightmare. They were poorly engineered, poorly assembled, and often went boom after 60,000 miles. I don't care if they power the Zonda.

BRM H-16 - How in the hell did they think it would ever work?

Underrated:

Hudson H-Power Inline 6. Gobs of power.

 

[Slash]

Wow, Savage I hope you are not talking about the venerable "Slant 6". Those things were so reliable, consistent and maintenance free that they were used in massive amounts of farm equipment, industrial applications, marine, military, machinery and oh yea, cars.

My dad bought a 69 Belvedere for $100 just to get back/forth to work while we swapped intake manifolds on his regular ride. Turns out, the darn thing just wouldn't die. Zero maintenance, no oil changes, nothing. 3 years later, with 325,000 on the odometer (yes, 1969 with over 300k) he finally sold it running strong.

They were not pretty. They weren't very fast. Not much hp, but comparable @ ~ 100 hp. That unique gear reduction starter Mopar used sounded funny. But they ran. And ran. And ran.

A friend and I each picked a car from his dads salvage yard with good engines. He picked a Chevy, forget which. I picked a Valient w/slant 6. We drained the oil. We started them, put a brick on the gas pedal and waited. The Chevy died in 10 min. My slant 6 ran for 2 hrs before slinging a rod through the oil pan.

Not reliable? I disagree.

I think he was talking about the LH engines they put in Dodge Stratus's etc. A V6 is a totally different configuration to a Slant 6.

 

[CAMAROBOY69]

I still think the I300 Ford engine is one of the best engines ever made to this day.

Worst engine I can think of right away is the V6 3.4 that is in the 93-97 Firebirds and Camaros. Those engines are very underpowered and very unreliable. The 3.8 and LT1 engines are great in those cars. But dang that 3.4 is such a piece of crap. If you have that in your car, do yourself a favor and sell it.

Ahh another bad engine depending on the vehicle location is the 2.8. Its great in some vehicles but terrible in a 4x4 S10. Most underpowered engine / vehicle combination I have seen in my life. Yes I had a 4x4 S10 with this engine and went through 2 of them. Gave up and sold the truck. On a side note I had the 2.8 in a Beretta and it was very reliable. Oh now that I think about it I think this engine was also in one of the 80s Camaros. Yuck.

 

[Slash]

I still think the I300 Ford engine is one of the best ever made to this day.

Worst engine I can think of right away is the 3.4 that is in the 93-97 Firebirds and Camaros. Those engines are very underpowered and very unreliable. The 3.8 and LT1 engines are great in those cars. But dang that 3.4 is such a piece of crap. If you have that in your car, do yourself a favor and sell it.

I worked on an early 3.8 once and it was a pile. I still think they are decent though. 3.4's are total trash.

I agree about the 300 I6. I can't tell you how many of those I've seen in the 500,000+ mile range with nothing but a few oil changes. They have been known to outlast the vehicles they've been put in.

 

[MrWednesday]

Wow, Savage I hope you are not talking about the venerable "Slant 6".

The "v6" should have been a clue that he was not talking about a /6 (which is an inline-6).

 

[Conbon14]

The audi tt 1.8 t has forged internals 👍

 

[Badasp5.0]

Worst engine I can think of right away is the V6 3.4 that is in the 93-97 Firebirds and Camaros. Those engines are very underpowered and very unreliable. The 3.8 and LT1 engines are great in those cars. But dang that 3.4 is such a piece of crap. If you have that in your car, do yourself a favor and sell it.

.

Add the 3.1 to the list too. Hell add the whole GM 60 Degree V6 family from 2.8 to 3.4 all POOP.

 

[Anna+Reece]

Here's an underrated motor.

Nissan KA24E. I have a bone stock one in my 240 and the thing's got balls. I don't see why everyone thinks you need some SR or RB or whatever to drift, I actually do a lot better in my stock KA-E 240 than some people with swapped 240s.

I can be pinning it at 4000 RPM in third and I am gaining on V8 RX7s. Though maybe my car being totally gutted has something to do with that.

 

[Tyger]

Rover V8, rebored or vanilla went in so many UK sports cars (and kits including numerous Cobra replicas) from the late 60s til...well to date really. Perhaps not the most efficient engine ever but definitely versatile and adaptable.

 

[High-Test]

Rover V8, rebored or vanilla went in so many UK sports cars (and kits including numerous Cobra replicas) from the late 60s til...well to date really. Perhaps not the most efficient engine ever but definitely versatile and adaptable.

Indeed. And, it was the first production turbo engine in the 1962 Oldsmobile Jetfire.

 

[BKGlover]

This is five pages in and no one has mentioned the one engine that, almost unanimously, was canned by both owners AND mechanics? Wow.

Best: I've got nothing.

Underrated: It came from the factory with 210 HP, but if not overly-abused, the 7.3L International Powerstroke V8 will outlast the truck itself, not an easy task as the 90's Ford Super-Duty still outnumbers almost anything else around here, and they are ABUSED.

Worst: This one is a legend. I give you the 1978-1985 Oldsmobile 350 Diesel.

EDIT: Hey, I found the article recalling some of the worst US engines. Here ya go.

 

[Slash]

This is five pages in and no one has mentioned the one engine that, almost unanimously, was canned by both owners AND mechanics? Wow.

Best: I've got nothing.

Underrated: It came from the factory with 210 HP, but if not overly-abused, the 7.3L International Powerstroke V8 will outlast the truck itself, not an easy task as the 90's Ford Super-Duty still outnumbers almost anything else around here, and they are ABUSED.

Worst: This one is a legend. I give you the 1978-1985 Oldsmobile 350 Diesel.

EDIT: Hey, I found the article recalling some of the worst US engines. Here ya go.

The old 6.9 and 7.3 IDIs were nasty engines. The new ones are cool though.

 

[High-Test]

You're bang-on about the olds diesel. You know, they do make great boat anchors.

 

[Slash]

You're bang-on about the olds diesel. You know, they do make great boat anchors.

You can't question their reliability.

 

[Bopop4]

Honda XR100 engine.

I have only ever heard/seen one of these engines go south once.
And that was because the cylinder and piston were VERY scored, someone probably ran it for a bit without oil.
But the thing still ran. (A ton of oil out the exhaust though.)

As long as you do regular maintenance on them, they'll last forever.
The fact that some guys in Japan made a 4-valve head big bore kit is a testament to its popularity.



Same with its brothers, Z50 all the way to the big 650 single.

 

[Slash]

Honda XR100 engine.

I have only ever heard/seen one of these engines go south once.
And that was because the cylinder and piston were VERY scored, someone probably ran it for a bit without oil.
But the thing still ran. (A ton of oil out the exhaust though.)

As long as you do regular maintenance on them, they'll last forever.
The fact that some guys in Japan made a 4-valve head big bore kit is a testament to its popularity.

Same with its brothers, Z50 all the way to the big 650 single.

I have never heard a bad thing about a Honda 200X motor either.

 

[BKGlover]

The old 6.9 and 7.3 IDIs were nasty engines. The new ones are cool though.

Nasty how? Wait, I need to add that I have the 7.3 Turbo. Also, when the this run came to an end, we got the new 6.0L. Cool maybe, but it's funny that I see 90s Powerstrokes towing brokedown 00s Powerstrokes.

 

[Slash]

Nasty how? Wait, I need to add that I have the 7.3 Turbo. Also, when the this run came to an end, we got the new 6.0L. Cool maybe, but it's funny that I see 90s Powerstrokes towing brokedown 00s Powerstrokes.

Nasty like good. Last a long time, reliable, adequate power for the times, etc. 90s Powerstrokes originated in the very early 80s.

 

[BKGlover]

Nasty like good. Last a long time, reliable, adequate power for the times, etc. 90s Powerstrokes originated in the very early 80s.

Cool. Wasn't sure about the lifespan, just know I have one and a lot of the 90s models had one. 80s are hard to come by anymore.

 

[Slash]

Cool. Wasn't sure about the lifespan, just know I have one and a lot of the 90s models had one. 80s are hard to come by anymore.

I think that really depends on where you are. I can get ahold of a complete running truck rather easily. I can think of, oh hell, probably 25 or so '80s trucks running around up here, within a 15 mile radius. Most very well taken care of. My neighbor actually owns a 1981 F250 flatbed. It's green. I saw an '84 with a 7.3 last night (took pics). It originally was an extended cab 6.9.

 

[Fran1001]

One of the best engines(three actually) I've ever seen, and I've seen a lot of them, is a 4.5 straight six in my Land Cruiser. That thing is a beast, with its low-end torque and actually, all round grunt.

The only bad thing with this engine is mileage.
You tend to get 10-11 MPG with this thing on a bad day, and that's not a nice thing when petrol costs almost 7$/gal.

Second best engine I know is the Boss 302, monster of an engine, and Mercruiser Alpha 350, which is "basically" a GM(block and some other parts); although American V8s are scarce here. (I had both of those in my dad's workshop, still have two Mercruisers.)

Third are the Fiat FIRE engines, indestructible babies. Extremely light engines, good power, rev happy, and you can run them forever. Unless crappy Italian electronics stop them, e. g. my Uno.

One of the worst engines I've seen is the Yugo 45 engine which is a licensed Fiat engine,(oh, the irony here), which is badly built, drinks petrol like a Bavarian does beer, and you're lucky if you get 50k miles on it. 👎

And the most underrated one, no idea here. Really don't know for now, if I remember, I'll post it, but can't think of anything now.

 

[SVT Cobra GT]

Here are a few suggestions of good engines;

Suprised no one has mentioned the Cosworth YB, been used for over 25 years and loved by nearly every Ford fan.

Cologne V6, powered the Sierra XR4, Capri Injection, Granada and even the S197 Mustang in a 4.0L variant.

3.0 Essex V6, powered many European Fords and even TVRs in the '60s and '70s, the only problem with it was, it was designed to run on diesel as well as petrol. Shortly before it was released Ford U-turned on the idea of the diesel versions and therefore it became very heavy overall. Even the 3.5 Rover V8 was lighter than this. But still great engine.

Modular V8 - Powered a lot of cars over it's life.

And finally possibly THE greatest engine ever..........the Pinto! It powered the Ford Pinto, Escort RS2000, TVR 2000s and my car.

 

[Slash]

I'm a ford guy through and through but Cologne V6's plain suck. I had one in my Bronco II and it either never ran right or broke down frequently leaving me stranded. My mom broke down while 8 months pregnant with my sister and had to walk 10 miles to get home and call my dad at work.

As far as the Boss 302 motor, there is soooooo much going on with that over a stock 302 I could talk for a few hours about that motor alone.

 

[Tyger]

I'm a ford guy through and through but Cologne V6's plain suck. I had one in my Bronco II and it either never ran right or broke down frequently leaving me stranded. My mom broke down while 8 months pregnant with my sister and had to walk 10 miles to get home and call my dad at work.

I can't help wondering if you would be a little more lenient if it had come out of Detroit? You're basing your opinion on one (admittedly first-hand) experience but I'm sure for every 10 reliable US-derived Ford V8 engine there is one bad apple too. There are so many factors involved in any vehicle and its application.

 

[MrWednesday]

I don't think all Colognes have issues, but the Wikipedia article on the engine mentions a few weak points on the 2.9L, and I've seen other mentions of the weaknesses in the design of the heads. Supposedly, most of the issues were resolved when Ford bumped the engine up to 4.0L.

 

[savage388]

Something I'll add to the list of underrated engines, the lt1 is the hated stepchild of the sbc world but after owning one there's not one thing it doesnt do well at.

 

[Badasp5.0]

Something I'll add to the list of underrated engines, the lt1 is the hated stepchild of the sbc world but after owning one there's not one thing it doesnt do well at.

They weren't bad motors except the whole early opti-spark issues. They just got overtaken by technology.

 

[sik180sx]

What about the sr20det?

 

[Tornado]

I can't help wondering if you would be a little more lenient if it had come out of Detroit?

I think he would be a little more lenient if the engine wasn't one that was known to have problems with the heads when put in heavier cars, just like the Essex V6 of similar vintage which popped head gaskets with early-Dodge Neon regularity.

They weren't bad motors except the whole early opti-spark issues. They just got overtaken by technology.

Also doesn't help that that these days its usually easier to get bigger power out of the earlier L-98s.

 

[savage388]

Also doesn't help that that these days its usually easier to get bigger power out of the earlier L-98s.

Not at all actually, the only way the l-98 could make power is with a short runner intake similar to the lt1 style one, the long runners were an awful design. The only advantage is that it's just a small block so people have a greater selection of heads, but once you change them it's not really a L-98 anymore. The lt1 is a much more refined engine IMO having seen both.