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  #49  
Old 11-27-2012, 08:58 PM
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Re: V6 Passing Performance

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Originally Posted by padgett View Post
Looking at the gears and the torque spread of the Pentastar, I doubt that road performance will change that much. There is a new "granny" first that few will use except in parades. 8th would have it turning about 1400 rpm at 60 so cannot use much below. 7th is the same as 5th now so there is really just one new gear in the spread and I would not be surprised if it often skip shifts.

Bottom line, the '14 GCs are known to be receiving a 3.42ish rear gear. The Ram 1500 also has the Pentastar 8 speed but to get 25 MPG highway the HFE gets a 3.22, adaptive grille. and a tonneau cover. With a 3.55 it drops to 23 mpg.

So I expect the '14 V6 with 8 speed to be rated 24 MPG highway and maybe 25 if the EPA does their usual rounding trick.

That assumes no change in the engine. OTOH a new set of peakier cams could narrow the torque band while kicking up the peak. The 8 speed could make this possible and if so add another mpg.

Where the 8 speed will really help is with the Hemi which has enough torque for a 1200 rpm cruise and even more so the diesel.

Further, not much difference in the models under 4500 lbs and more for those over 5,000. And then there is the magic of advertising.

Final kicker could be the availablity of the 8H70, if production is slow to ramp it could hold up the diesel further.

What will be the most interesting will be the prices of the various options. Right now CJF could sell more than they are making.
Right, but this also doesn't account for possible direct injection being added, along with turbo options as the Pentastar if I'm not mistaken already has forged internals mapped and ready to go, if not already being used. Fiat has also stated the Hemi will be phased out, so either the turbo V6 will replace it as Ford is doing, or a smaller 4.5-5 liter V8 Pentastar maybe? This would follow in the foot steps of all the other auto makers as well like Mercedes and BMW along with Audi. I think Infinity just started doing it with thier new SUV line up, and I expect Lexus to follow suit as well.
Any of these engine options would change the game quite a bit.
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  #50  
Old 11-27-2012, 11:37 PM
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Re: V6 Passing Performance

Direct injection sounds great but secondary problems are the issue that offset the advantage of near diesel compression ratios with trash gas.

The most common is the formation of carbon and sludge deposits around the intake valve and passages. Oil can come from many locations, crankcase ventilation for one, weaping vlave guides another.

Conventional injection and carbs wash these deposits away as the atomized vapor flows past the intake valve. With DI, this does not happen. Problems like this and others with combustion in general is why Hemis have two spark plugs with staggerd (not simultaneous) fire and is why gasoline direct injection has been slow coming.

Diesels have had DI for years (is part of why they are more efficient) but with a big difference: diesels run at WOT all of the time and use turbos for even greater air flow. Diesels do not have manifold vaccuum (why they have vaccuum pumps) and manifold vaccuum is part of the reason the deposits form (those who have not wanted to put up with combustion theory really won't want to hear a chemistry lesson).

The owner's manual for my aunchient Jag XK-150s included instructions on how to remove the heads and decarbonize the valves (and with DOHC that ain't easy). CJF won't even provide owners with service manuals & is not easy to pour a 6 3/4 oz Coke bottle of water down the intake.

Water injection anyone ?
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  #51  
Old 11-27-2012, 11:45 PM
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Re: V6 Passing Performance

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Originally Posted by bigrboland View Post
Not what I experienced. When we decided on getting an SUV, we narrowed our choices down to the WK2 and a 4Runner because of their 4x4 capability. The WK2 had a much nicer interior and there was a big difference between the V8 in the WK2 and the V6 in the 4Runner. Because of those two things, we went with the WK2 V8.
Did you drive a 5th generation 4Runner? The reason I ask is because the 5th generation isn't as quick as the 4th generation 4Runners.
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  #52  
Old 11-28-2012, 06:11 AM
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Re: V6 Passing Performance

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Did you drive a 5th generation 4Runner? The reason I ask is because the 5th generation isn't as quick as the 4th generation 4Runners.
I did. It was a 2012.
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  #53  
Old 11-28-2012, 06:33 AM
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Re: V6 Passing Performance

Quote:
Originally Posted by padgett View Post
Direct injection sounds great but secondary problems are the issue that offset the advantage of near diesel compression ratios with trash gas.

The most common is the formation of carbon and sludge deposits around the intake valve and passages. Oil can come from many locations, crankcase ventilation for one, weaping vlave guides another.

Conventional injection and carbs wash these deposits away as the atomized vapor flows past the intake valve. With DI, this does not happen.
From what I have been reading, the popular catch cans become a necessity with DI, while remain just a cool thing to do with conventional injection engines.
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  #54  
Old 11-28-2012, 10:50 AM
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Re: V6 Passing Performance

The new 4-Runners really got hit with the ugly stick. I passed one the other day, and was surprised at it's ugliness....really bad IMO.
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  #55  
Old 11-28-2012, 12:14 PM
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Re: V6 Passing Performance

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Originally Posted by kkreit01 View Post
The new 4-Runners really got hit with the ugly stick. I passed one the other day, and was surprised at it's ugliness....really bad IMO.

Love or hate the look, it's definitely distinctive. And you don't see many. Our WK2's on the other hand, I see multiple times a day.
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Old 11-28-2012, 02:23 PM
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Re: V6 Passing Performance

We rented the V6 for a week and spent 10 minutes driving the V8. IMHO, there was no comparison...the V6 was nice, but it wasn't fun. When you are already spending $40k+, what is an extra $2k? An extra few bucks a week for gas is also peanuts to me, so MPG wasn't even a consideration. The only reason we didn't go w/ an SRT8 is my wife didn't like the seats.
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  #57  
Old 11-29-2012, 09:43 PM
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Re: V6 Passing Performance

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Originally Posted by kkreit01 View Post
The new 4-Runners really got hit with the ugly stick. I passed one the other day, and was surprised at it's ugliness....really bad IMO.
I agree. They really screwed up the styling with the new generation.
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