Re: 4.7 vs 5.2

From: M.B. (mailinglists@moparhowto.com)
Date: Thu Sep 30 2010 - 06:54:38 EDT


Interesting. The only comparison I have is my '95 CC with the 5.2 and
the auto vs. a friend's 2000 CC with the 4.7L and the 5 speed. Hard to
compare with a 2nd gen vs 3rd gen (apples to oranges) though I think the
3rd gen is somewhat heavier. We both have the same final drive (3.55)
but I have the lighter weight 8.25 vs. his 9.25 rear end.

My personal impressions are that (stock) his is quicker to 40mph with
the 5 speed, but I think I'd beat him to 80mph. I think with the stock
size tires it would be more even, my 30" tires are a good 2" taller than
stock, and MT tires on chromed steel wheels they weigh a lot more than
his 31" street rib tires on aluminum rims. 1st is just too tall on my
2nd gen with the taller tires, it doesn't upshift to second until almost
50mph. His, on the other hand, is a total dog in 3rd gear at passing
speeds on the freeway in comparison. With the taller effective gearing
my truck at 60mph can downshift to 2nd, he has to go to third.

The 5 speed makes his more fun, but with my commute I don't mind the
auto too much.

Toss in the MP PCM (at least on my second gen) and it gets a lot closer
even up to 40 if I don't bog the crap out of it off the line. The 2nd
gen has a real weird "dead spot" around 2800rpm that the MP PCM takes
care of. Beyond that forget about it. With the MP PCM though the
horsepower difference tips in the 5.2L's favor. Fuel economy goes to
the 4.7L, he gets about 2mpg better than I get consistently.

Until you get them on a dragstrip it's all speculation though. If the
Durango has 3.94 gears and the Dakota has 3.55s, that could definitely
make a difference in how snappy it feels too, especially off the line.

M.B.

On 9/30/2010 2:47 AM, Barry Oliver wrote:
>
> After having driven the Dak and the Dur [?] back to back, one thing I
> have noticed is that the 4.7 seems like an awfully peppy motor
> compared to my 5.2. I mean I know the numbers are better on paper,
> but I guess I just assumed that since the they were of comparable
> mileage, age, and size that the butt dyno would register about the
> same. Apparently the extra weight of the Durango is much less of a
> hindrance than the big tires on the Dak. I will say it seems to rev
> higher, but the Dak seems to have to work harder to attain and
> maintain a given speed. Hmmmmm.
>
> I have been going through a spell of "want a new toy-itis" lately,
> looking at newer Daks, Ram's and just generally trying to convince
> myself that there is no practical reason to trade off my beloved Dak
> for something else. It didn't help that the GF wrecked the Dak a
> little last week [nothing major, just mashed the brushguard]. I think
> the only thing that has really put a damper on my enthusiasm is the
> fact that the only thing for sale around here are Ram's [too big for
> my purposes] and 2wd V6 Dak's [too small for my purposes]. I guess
> the only thing I can say in my defense is that I fully intend to buy
> as close to the same configuration as I have now, and those seem to be
> few and far between....
>



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