Top Speed, 6th Gear & What were they thinking?

I just got back from a 1,550 mile round trip to Telluride, CO and back, I got about 20.6 miles per gallon (per the computer), which is quite good since 80-100 was the cruising speed, and it might have been at the higher end of that range on average.

But this 6th gear just Sucks Ass! It is WAY to tall. I was recently watching a top speed video run for a GT350. It pulled pretty quickly to top speed in 5th gear and kept on pulling past peak power (7800rpm) and into over rev with top speed being 170mph at around 8200rpm.

If the GT350 were geared properly it looks like it could go a little faster. Any speculation on this? Just curious.

In the category of what were they thinking...... I can only guess that the bad selection of the 6th speed gear ratio was done for fuel economy. But with the excellent fuel economy that I received at 90mph (20.6 mpg), It seems like the car (in six gear) starts becoming more efficient the faster I go. Maybe I would get better gas mileage at 60mph in 5th gear rather than 6th gear?

And then the final question / rant. Based upon my quick multiplication while driving and looking at the Revs vs MPH, the theoretical top speed of the car in 6th gear is around 270mph. What the hell where they thinking????? Six gear is WAY to tall even if it is an overdrive. I can't seem to make sense of the need for a six gear this tall if for fuel economy alone.

This plus the exhaust valves closing are why I don't use 6th until 80MPH most of the time. It's like the car turns into an Ecoboost Mustang in 6th. LOL

lol yeah! Sixth gear sucks! Although I believe it was designed that way intentionally in order to increase fuel efficiency when you are cruising calmly at highway speeds

ORRRRR.... maybe Ford wanted to give us a great excuse to cruise around at 8K+ RPM (in 5th) to unleash that magnificent voodoo engine sound :lol:

The GT350 will do close to 170 MPH in 5th gear. There isn't a track in the US that will allow you to go that fast in stock trim and the car doesn't have the power to go much faster under any circumstances. So if I were a Ford engineer, why not utilize a gear that would provide better fuel economy. For those of us that DD our GT350's, I'm fine with 6th gear the way it is.

GT_Dave said:

The GT350 will do close to 170 MPH in 5th gear. There isn't a track in the US that will allow you to go that fast in stock trim and the car doesn't have the power to go much faster under any circumstances. So if I were a Ford engineer, why not utilize a gear that would provide better fuel economy. For those of us that DD our GT350's, I'm fine with 6th gear the way it is.

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I second this. I like 6th gear for cruising, keeps the wife happy

GT_Dave said:

The GT350 will do close to 170 MPH in 5th gear. There isn't a track in the US that will allow you to go that fast in stock trim and the car doesn't have the power to go much faster under any circumstances. So if I were a Ford engineer, why not utilize a gear that would provide better fuel economy. For those of us that DD our GT350's, I'm fine with 6th gear the way it is.

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If I were a Ford engineer, I'd engineer the 6th gear for drivability and usefulness unless it's under the direction of Ford executives. Nobody buys GT350 for the fuel economy. You're not fooling anybody.

BoomBoy said:

If I were a Ford engineer, I'd engineer the 6th gear for drivability and usefulness unless it's under the direction of Ford executives. Nobody buys GT350 for the fuel economy. You're not fooling anybody.

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of course that might have meant more than $1300 in gas guzzler tax for all of us

ALL CARS HAVE TO MEET FEDERAL REQUIREMENTS LOLOLOLOL 6th gear is their for drivability, fuel efficiency and emissions.

BoomBoy said:

If I were a Ford engineer, I'd engineer the 6th gear for drivability and usefulness unless it's under the direction of Ford executives. Nobody buys GT350 for the fuel economy. You're not fooling anybody.

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Sure - we didn't buy the GT350 for fuel economy. But the thing also has cruise control... certainly wouldn't want to use that with 5th gear at typical highway speeds. It's nice to have a beast that can be tame and somewhat efficient (given the beasty capabilities).

Also - and feel free to flame on - Who is running this thing to 170 anyway? Where? What's the point? The only place to do that legally is on a closed track - likely an airstrip - more likely all alone. Kinda boring after 1 time doing it. If on the street - sure been there ..well not quite 170 but you get the point - but that's just.... asking for life changing consequences on multiple fronts. My 392 has a higher top end than this thing, I've had this up higher than the 392 by far.

MrCincinnati said:

Sure - we didn't buy the GT350 for fuel economy. But the thing also has cruise control... certainly wouldn't want to use that with 5th gear at typical highway speeds. It's nice to have a beast that can be tame and somewhat efficient (given the beasty capabilities).

Also - and feel free to flame on - Who is running this thing to 170 anyway? Where? What's the point? The only place to do that legally is on a closed track - likely an airstrip - more likely all alone. Kinda boring after 1 time doing it. If on the street - sure been there ..well not quite 170 but you get the point - but that's just.... asking for life changing consequences on multiple fronts. My 392 has a higher top end than this thing, I've had this up higher than the 392 by far.

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Of course, it is for bragging rights and when you are breaking the law with no cops around, of course. ;)

You still pay a gas guzzler tax on the GT350 and Ford does not even use a skip-shift to improve mileage. I remember trying to pass people on a highway in 6th and it was impossible. I always had to down shift into 5th. This is likely more to do with where the power band is on the GT350 and less about fuel economy.

Just as a contrast, My HC is an M6. I can pass easily in 6th. In fact, on the highway, I never need to drop to 5th to pass someone unless I'm trying to make a point This is likely due to the fat tq curve everywhere in the rev range. By the same token, at 80 MPH I'm turning 2300 RPM and getting no better than 18 MPG. I wish the HC had a 7th gear.

I guess my point is everything is a trade off. :cheers:

It's probably why I'm subconsciously always in 5th. I have to remember to put it in 6th for long drives.

Mike02z said:

You still pay a gas guzzler tax on the GT350 and Ford does not even use a skip-shift to improve mileage. I remember trying to pass people on a highway in 6th and it was impossible.

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Much love for the fellow Mopar owners here... however c'mon man if you couldn't pass someone in 6th it's because they didn't want you to pass them.. and at that point it's a race :bolt:

BoomBoy said:

Of course, it is for bragging rights and when you are breaking the law with no cops around, of course. ;)

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:cheers:

I kind of appreciate 6th being nice and long, but I DD mine. Sure it's great to get some fun back... uh... road action, but there's times where it's also fine to sit back, pop the shocks into normal, crank the stereo, and cover some distance.