Best Inline-6 ever made?

Messages
458
Location
United States
For passenger cars the Jaguar AJ6/16 4.0 is up there. Extremely overbuilt and unkillable.

B9058F7E-99C4-4C88-9FD4-375BF040A923.jpeg



For everything else there’s a clear winner:

DD Series 60
6A48F1BA-E119-4D28-AA0F-B54225F427BF.jpeg
 
Messages
6,433
Location
New England
I'll bite...

I'll nominate the Jeep 4.0. Millions made. Not my favorite motor by any means but definitely deserves a spot in this thread.
My parents had the related 4.2L I6 in a 1984 CJ-7 and 1985 Amc Eagle Wagon. The Jeep was running strong at 225k no engine problems and the AMC Eagle my dad(regional sales manager car) gave to mechanic running at 298k.
 
Messages
151
Location
Texas
My 82 F150 with 300 knocked like a b**** for years in hot dry weather, but still went 170k before burning oil. I guess it could've been tuned better or just run premium unlead. I was a fuel distributor, and had the gas, but like the plumber didn't have time to tweak own stuff.
 
Messages
128
Offcourse we wont forget the toyota 2jz and nissan rb26. But those are out of my league.

Then i would say the bmw n52 which is in my e90.

This was the last bmw inline 6 which produced almost 100hp per liter anr revved to 7000 rpm.
In order to achieve that it was built with interesting technologies.
Valvetronic variable intake height control which replaces the throttle valve.
Vvt on both intake and exhaust.
The 2.5 has an almost sqaure bore x stroke.
2 stage disa intake manifold whith different chambers for better cylinder fillage.
Electric water pump which let it run at 110 celcius while cruising so the block expands and it has less drag.
When the ecu notices you are driving harder it lowers the temp to a race car 80 degrees for better air fillage tighter tolerance.
Magnesium composite shortblock.

Everything around it is not extremly realiable due to the complexity and it likes to leak oil.
However the engine itself is known for getting above 500k miles.
 

Attachments

  • 5b79306s-960 (1).jpg
    5b79306s-960 (1).jpg
    126.3 KB · Views: 6

JTK

Messages
13,234
Location
Buffalo, NY
I had a 1979 Ford Granada 2dr with an inline 6 and C4 trans, but I don't recall if it that 6 was a 200 or 250? It had a tiny one barrel carb, but overall moved out pretty well. The non-vacuum boosted brakes were very scary. It had power steering, no A/C and power nothing. Didn't even come from the factory with a radio. Was my parents car that they gave to me to use when it was on it's last legs. I was 18.

Second was the 4.0 in my 1994 Jeep Cherokee.

Third was the 4.2 in my 2005 Chevy Trailblazer.

They were all pretty neat in their own way. The Jeep being a 2wd w/ 5spd moved along the best.

To me, the sweet spot for inline 6's was the fuel injected Ford 4.9 / 300. What they were in fell apart long before that engine did.
 
Messages
11,186
Location
Colorado Springs
Offcourse we wont forget the toyota 2jz and nissan rb26. But those are out of my league.

Then i would say the bmw n52 which is in my e90.

This was the last bmw inline 6 which produced almost 100hp per liter anr revved to 7000 rpm.
In order to achieve that it was built with interesting technologies.
Valvetronic variable intake height control which replaces the throttle valve.
Vvt on both intake and exhaust.
The 2.5 has an almost sqaure bore x stroke.
2 stage disa intake manifold whith different chambers for better cylinder fillage.
Electric water pump which let it run at 110 celcius while cruising so the block expands and it has less drag.
When the ecu notices you are driving harder it lowers the temp to a race car 80 degrees for better air fillage tighter tolerance.
Magnesium composite shortblock.

Everything around it is not extremly realiable due to the complexity and it likes to leak oil.
However the engine itself is known for getting above 500k miles.
Everything you said, and leaks are not an issue as long as you change in time that leak from OFHG or VC bcs. belt sucked into engine is game over in 99% of cases.
But, overall M20 and 30 were really, really stout engines. I had E34 520i with M50, mades some 485,000 km, sold it to a guy who drove it next 5 years and than lost trace once I move to the US.
 
Top