Why did Chrysler replace the Slant with a V-6? Was it because of emissions, effeciency, or the need for something new? Another question, why has every body gone so crazy over V-6s? Are they more effecient than inlines or something?

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82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

There were probably lots of reasons, but here are a few: 1.weight, size, and ease of fuel distribution. V-6's are much smaller and lighter than a slant, and EFI had not been perfected when the decision to drop the slant was made. The V-6 is inherently easier to balance the fuel on than an inline engine. Now here is the cynical answer: The slant was too good. Too many people drove them too many miles, and kept them too long, without trading them in on new cars. Mopars biggest competitor for many years was its old cars that were still running fine.

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BINGO!!! Mopar could NOT HAVE the slant competing against thier new 3.0 V6, as the V6 would have come out on the losing end.

Even amongst Ford and Chevy enthusiasts that I've talked to, (they think I'm a half-bubble off level for wanting to build and race one), but they acknowledge the engine as being one of the most well-known for reliability as any other.

Roger

The Slant 6 was too long to fit crossways under the hood of the front wheel drive cars.

Nobody wanted straight 6ers any more Look who ever though ford would do away with the 300 6

Just think how wide a omni would have to be to fit a sland... It might lean forward too!

a v6 crank is about 2/3rds the length of the slants . . . there's a 20 lb saving right there

i beleive the 3.0L was out with the slant for a while but the slant wasn't put in cars anymore by this time just trucks my guess would be that dodge thought they needed a change and they scraped the slant but it's pretty bad when you still see some driving around with out a rebuild to this day tells you something about he quality of the engine

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MOPAR OR NO CAR
1985 Ram
1975 Coronet
1998 Dakota

Parts commonality w/ 318 must've been a factor for the bean counters, too...

Seems I saw somewhere that they did research to equip the /6 with TBI in the eighties before they dropped it in favor of the V6. Of course a TBI would have suffered the same distribution problems as a carb.

D/W

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If it ain't broke, fix it!

The head was going to need to be redesigned to meet the (then) new emissions requirements. If you redesign the head you might as well invest in the rest of the motor.

As Dennis mentioned, parts commonality with the 318 was one of the big reasons they changed the truck motor. They had to develop the 3.9L for the Dakota. Manufacturing both the 3.9L (v-6) and the 3.7L (225 /6) probably didn't make sense. When they changed the body design (1993) of the full size truck, having a v-6 instead of the slant 6 let them shorten the nose a little.

In 1981, Dodge cars were all being moved to the K-car based platforms with the transverse 2.2L 4cyl. engine. (yes, there were a few holdouts, like the Diplomat) They needed the commonality & simplicity to save money. The company almost tanked, remember. They were doing what they had to to stay alive.

BTW, when you look at one of those 2.2's, you should be thinking "next generation slant 6" It's obvious the slant 6 design influenced the guys who designed the 2.2L.

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My truck is a Frankenstein creation
Built from the dead carcasses of others
And brought BACK TO LIFE!

mnecaise wrote:
I'm not exactly famillar with this /6 head. What items that head would need to redesign to meet emissions especially with multi-injection not single?
Oh yes, it is alike to that slant 6 to that 2.2L! In fact, one engineer did both. By the way my 1987 caravan has original 2.2L with 3 speed auto, working on 'van that former owner screwed up all the way except engine block itself!

Straight sixes, I loved them for how they runs and so much torque off the idle. Recently drove brother's 2004 Jeep TJ Unlimited 4.0L manual. Total torque brute but liked it and can feel it, need that than by ear, I'm deaf. V6 no way! Never had that same characters. I was from V8 & I6, /6 era but didn't drive them till this first caravan is my own car because got the license few years ago and still yet to move up to fully licensed due to money and time.

If I could and had money, determination then I'd find a way to transfer the /6's power from flywheel to the transmission via hydrulic or gears if engine is not too long to fit transversely. Otherwise find a small 2.5 or 2.8L diesel combo engine.

Cheers,

Wizard[/quote]

On the drawing board for the '80's was a 240+ CID slant block with a swirl port head like the magnum engines have now. The tooling for the /6 already had moved to Mexico in the 70's...so the bean counters 'deep sixed' the slant for the more modern platforms of the 3.8L in the Dakota, the later 'Magnum' series in the early 90's (3.9L, 5.2L, 5.9L, and 8.0L).
I'm wondering how long the V-6 will really last in the face of the 4.7L OHC V-8.

-D.Idiot

the 3.9L has already been phased out in favor of a variant of the new engine. I believe it's a OHC 3.7L v-6(?).

As for the head, the old head is a low efficiency "open chamber" design. It needs to be a closed chamber design, with quench and swirl to have a chance to meet later emissions requirements. The upper ring would likely be moved closer to the piston crown as well. The head needs more baffling under the rocker cover to reduce oil vapor. etc, etc, etc...

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My truck is a Frankenstein creation
Built from the dead carcasses of others
And brought BACK TO LIFE!

Yeah it's a 3.7L/225 based on the 4.7L V-8. Not to say anything bad, but my slant will eat my buddy's 3.7L Liberty Renegade alive on the highway...then again his gross weight sticker has a 3000 lb monkey on it's back over my actual vehicle weight too... (Then again his vehicle will smog better...but I get better highway mileage)....


-D.Idiot

Too complicated a question...#1 The American consumer has never desired a vehicle that would simply "run forever"" #2.. look for example "car and Driver "magazine will give the Truck of the year award to whoever has the most revised "coffee cup holder"!!...or "Optional X-Box capability" or something as realistically unuseable........even though the DODGE kicks everybody's ASS in the horsepower,torque,and everything else ratings!!! Believe me when I tell U ,,These comparo's are COMPLETELY BOGUS"!!!!! The Problem is that the MOPAR FATHERS believe this crap,and continuously play the stupid game!! My motto would be,"If u want a TRUCK, come to MOPAR:If u want something else ,Go somewhwre else !!!!