Why drive a truck with a big six cylinder?

[Ray Cecil]

Jim, I already have a chevy ignition, may as well french the induction.

[85lebaront2]

Jim, tell that to the late Carroll Shelby with what he did for Chrysler. The turbo Chrysler engines as originally built were 142 hp from 135 ci, after Shelby got through with the initial update it was 170 hp from 135 ci. With some other improvements (more boost from 12 psi to 15) I am getting right at 200 hp from that same 135 ci engine still with an 8 valve head with same side manifolds. The Maserati headed TC and the Shelby CSX used DOHC 4 valve heads on the same basic 2.2L engine. No lag I have ever really noticed, the biggest issue is the stall speed on the A413.

The variable vane turbo that the more recent Ford Powerstroke diesels use was pioneered by Shelby for the 1990 VNT (Variable Nozzle Technology).

[ArdWrknTrk]

Speaking of the maserati, Lee Iacocca died today.

He did a lot for that company and will be missed.


Bill, please have a look at the new carburetor problem thread.
Seems the guy rebuilt his 2300 and it won't idle right.

[ArdWrknTrk]

Bill,
 I mentioned Shelby in post #7.
He was a great race engineer and along with KarKraft helped defeat Ferrari at LeMans.

He and Iacocca also go way back.
Their many accomplishments together changed the way we look at cars today.

A 50% increase in hp is no joke. You did well!  

But this thread is about the I-6 (and others like it) powering pickups.
The Cummins was mentioned, and the Dodge slant six too.

So, "Why Drive a Truck With a Big Six Cylinder?"

[85lebaront2]

One word, Torque. As has been said, "horsepower is how hard you hit the wall, torque is how far you move it".

In 1986, the base engine on the crew cab F350 was a 300 six, Then it jumped to the 351, no 302 offered in that package. The DRW was not offered with the 300, base engine was the 351.

My first two pickups both were sixes, the 1958 F100 had the 223 and the 1977 F150, the 300. I hauled a heavy (Wolverine) 11 1/2 foot slide-in with that truck and we drove it up into Shenandoah Park over Christmas break one year, Matt rode either in the camper or middle of the seat as he was 9 or 10 at the time. We did need to get down into 2nd and even first going up Rt 33 into the park, but the 300 handled it.

My department at NNS had a number of Ford trucks while I was there, all but one of them powered by the 300, the only Ford that wasn't, was a 1997 F150, with the 4.2L V6.

[ArdWrknTrk]

The 300 was gone by then.

LOTS of fleet trucks were built with the straight six and really tall gearing.

I suppose the gas meter reader or the auto parts delivery guy didn't need a lot of capacity and the beancounters in corporate wanted a fuel efficient vehicle that didn't break down.

[Steve83]

1986F150Six wrote

Injectors may have been improved [?].

There were 2 designs that are almost impossible to distinguish while installed, but I've never found the Densos in a 4.9L of any age.



This makes it look like they were redesigned in '91:

85lebaront2 wrote

Steve, check the injector rail pressure on the early vs late EFI 300.

I've checked it on my Bronco (with '95 F150 engine & '96 Bronco 5.8L tank/pump) several times, and on my '95 F150 (with replacement pumps).  It's the same as the V8s (~35psi) despite the Ford specs at the bottom of this diagram saying it should be higher.



I've actually driven the Bronco (towing a trailer) at ~12psi (when it was running out of gas, and VERY slowly, just to get to the gas station).

ArdWrknTrk wrote

I thought the 300's injectors went from 'in manifold' to 'in head' at some point.

No.  AFAIK, no gas engine has injectors in the head, until maybe direct injection.  I've never seen it in a Ford, Saab, Nissan, Land Rover, Jaguar, BMW, Honda, Mitsubishi, VW, Dodge, GM...

ArdWrknTrk wrote

You might think that Ford would have had the fuel pump continue to run for xxx (circulating cool fuel through the loop)...

That could take a half hour, depending on ambient temp, so that's too much load on the battery.  And without manifold vacuum to regulate pressure, it would spike very high, creating a greater potential for leaks (including into the engine through a failing regulator, which is common).

[ArdWrknTrk]

ArdWrknTrk wrote

I thought the 300's injectors went from 'in manifold' to 'in head' at some point.

No.  AFAIK, no gas engine has injectors in the head, until maybe direct injection.  I've never seen it in a Ford.

Sorry.
I realize now that I was thinking of the AIR injection, that moved from the exhaust manifold to the head.

EGR kills DI engines.
The Mazda Skyactiv thing that works like diesel seems pretty cool though

[Gary Lewis]

I've read about SkyActiv, but still don't understand how it works.  I understand the words "13:1 compression" and "multi-hole injectors" and "dished pistons", but .......

[nic55kel]

quote "Steve83"
"No.  AFAIK, no gas engine has injectors in the head, until maybe direct injection.  I've never seen it in a Ford, Saab, Nissan, Land Rover, Jaguar, BMW, Honda, Mitsubishi, VW, Dodge, GM..."

The buick L67 supercharged 3800 has the injectors in the head - no room on the LIM with the supercharger sitting there.
Could be others but definitely rare.

Nic55kel

[ArdWrknTrk]

Funny,

I just mentioned this engine the other day, when Ray challenged my to say what kind of blower would fit on the 4.9

It really was an exciting engine for its time.

[nic55kel]

Yes I have two of them in my yard and a 4 speed Fiero GT- oh dear what to do?.
I really enjoyed driving my Buick regal GS with the L67.
The 300I6 is a torque monster but so is the L67 .

Nic55kel

[ArdWrknTrk]

Ahh, but put the L67 blower on the I-6!

Fiero,,,, the great car that never got a chance to grow up.
When GM began to realize that Pontiac's 'little project' would rip the wings off the flagship Corvette if development progressed, it was aborted.

That gas tank though....

[1986F150Six]

1986F150Six wrote

ArdWrknTrk wrote

He says in the comments that the head is not really optimized.
That it was a Ford test piece for fuel efficiency.

One of the reasons Ford developed the crossflow head for the 4.9L was a warranty issue. The fuel injectors were exposed to heat soak, since located above the exhaust manifolds, when the engine was cut off. A temporary fix was a cooling fan blowing across the injectors and continuing to run after the engine was cut off.

There were other prototypes as well [variable displacement and turbo].

Truth in reporting [or at least, trying to]


Steve83 wrote:

...a warranty issue. The fuel injectors were exposed to heat soak, since located above the exhaust manifolds, when the engine was cut off. A temporary fix was a cooling fan blowing across the injectors and continuing to run after the engine was cut off.
Are you saying the head was changed between '88.5 and '89?  Because the injectors are in the same location on my '95s, and they don't heat-soak or fail.  And of all the people to whom I've recommended deleting the '87-88.5 4.9L injector blower (which is probably in the low hundreds); none have mentioned any problems since.
Walk softly and carry a BIG SIX!!!
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Memphis, TN, USA, Earth, Milky Way


Steve83,

The same retired Ford engineer said that the crossflow head did address the higher than desired warranty claims regarding injectors, but the primary reason for the development of this head was for improved fuel efficiency and reduced emissions.

David

[Steve83]

So are you saying the head was changed between '88.5 and '89?

[1986F150Six]

Steve83 wrote

So are you saying the head was changed between '88.5 and '89?

I do not know the answer to that. The crossflow head I have mentioned was never offered to the public.

[Steve83]

Does that mean it was never put into production?  If not, I don't understand its relevance here.