Hate going from 5th gear to 6th gear.

[tacthecat]

5th (.911) & 6th (.743) are OD.

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[CTR1633FK2]

5th (.911) & 6th (.743) are OD.

I thought you will have to multiple with the final drive too.

 

[tacthecat]

That would be the "Final" ratio. To my knowledge only an electric car might have a 1:1 final ratio.
BTW the CTR top speed with 1:1 would be about 513 mph with no friction losses.
Overdrive and gear ratios in a motor vehicle usually refer to the transmission, you'd then multiply that by the front- or rear-end ratio to get the final drive ratio

 

[CTR1633FK2]

Don't know if they change the definition of overdrive or not. In wikipedia they say that if you can't reach the top speed with that gear, that gear will be called overdrive.
https://en.m.wikipedia.org/wiki/Overdrive_(mechanics)

 

[tacthecat]

Not sure Wikipedia is a great source for correct technical information.

A more common, and generally accepted, definition:

Overdrive | Definition of Overdrive by Merriam-Webster
https://www.merriam-webster.com/dictionary/overdrive
Definition of overdrive. 1 : an automotive transmission gear that transmits to the drive shaft a speed greater than engine speed. 2 : a state of heightened activity. going into rhetorical overdrive.

Almost every demonstration of the CTR shows top speed is attained in 6th gear.

 

[TheBigG]

Maybe a bit off topic but don't you guys think the rpm in 6th gear is stupid high?
At 110 km/h (70 miles/h) I have 2500 rpm. In some countrys the legal speed on highway is 130km/h (80 miles) and at that speed I get 3000rpm. Cruising at 3000rpm is neither comfortable nor economical.
Our Kia Optima GT in 6th at 70mph is doing aprox. 1800rpm...

 

[CTR1633FK2]

It's still better than the S2000 6th gear or the DC's 5th gear....

 

[Fk8 4343]

Cruising at 3000 rpm puts you above the boost threshold and makes maximum torque available to you whenever you want it. For a small displacement turbo engine, engine rpm for highway cruising is not as detrimental to fuel consumption compared to a NA V6 or V8 (although the bigger engines would have plenty of torque at lower RPM so they wouldn't need to have such a high ratio 6th gear).

At 75mph, the new honda accord that uses a detuned Type R engine would be at 2500 rpm (6th gear, manual) compared to ~1800 rpm for the 10-speed auto version. The 10-speed downshifts whenever you need more torque. Both accords have the same government highway fuel rating of 32mpg which is better than the type r 28 mpg.

Our Kia Optima GT in 6th at 70mph is doing aprox. 1800rpm...

Is the Optima GT also a 2.0 turbo? If it is manual, do you have enough torque for accelerating at 70mph/110kmh in 6th?

 

[fmoua916]

My old si was like 4,000 rpm at 80 mph haha

 

[boosted180sx]

Maybe a bit off topic but don't you guys think the rpm in 6th gear is stupid high?
At 110 km/h (70 miles/h) I have 2500 rpm. In some countrys the legal speed on highway is 130km/h (80 miles) and at that speed I get 3000rpm. Cruising at 3000rpm is neither comfortable nor economical.
Our Kia Optima GT in 6th at 70mph is doing aprox. 1800rpm...

Nothing seems high after having a s2000, or a 8th/9th gen SI.
My ILX with the 8spd dct on the other hand, sits at like 2k rpm at 80ish mph lol

 

[TheBigG]

Is the Optima GT also a 2.0 turbo? If it is manual, do you have enough torque for accelerating at 70mph/110kmh in 6th?

Yes! It is a 2.0 twin scroll turbo with 260 lb-ft from 1500 rpm and 245hp.
6 speed auto. with torque converter.
I think the name in the US is Optima SX 2.0T

Ok! So it kan be much worse...
I think it would have been better with like 2000rpm at 70mph in 6th.

 

[SpooRk]

Cruising at 3000rpm is neither comfortable nor economical.

Can you explain what is actually uncomfortable about driving at a certain RPM. Do you mean because the engine is louder? Cause I really don’t have an issue with the sound of the engine at those speeds. I have more of an issue with the road noise at that speed. Not that I’m complaining, but I just think the road noise would be more annoying than engine noise. Unless you mean uncomfortable in another way..?

 

[Vortexhunter]

Maybe a bit off topic but don't you guys think the rpm in 6th gear is stupid high?
At 110 km/h (70 miles/h) I have 2500 rpm. In some countrys the legal speed on highway is 130km/h (80 miles) and at that speed I get 3000rpm. Cruising at 3000rpm is neither comfortable nor economical.
Our Kia Optima GT in 6th at 70mph is doing aprox. 1800rpm...

And this car's main purpose is to be driven on a motorway at road speeds? They designed the gearbox for track use with close ratios, any other use is secondary. A higher 6th would hinder performance.

 

[TheBigG]

Can you explain what is actually uncomfortable about driving at a certain RPM. Do you mean because the engine is louder? Cause I really don’t have an issue with the sound of the engine at those speeds.... Unless you mean uncomfortable in another way..?

Right now I have good winter tires on 19 inch rims (235/40-19) so the road noise is not a problem. It is the engine and the exhaust. Weird...all the reviewers complain about lack of exhaus noise but I think a louder system would be a problem in everyday driving. From time to time I have to drive 500-600km to work in other region. I just think that the cabin noise would make me tired after 5-6 hours trip.

And this car's main purpose is to be driven on a motorway at road speeds? They designed the gearbox for track use with close ratios, any other use is secondary. A higher 6th would hinder performance.

Weeeell... let's not forget that this is a hatch with four doors and a big boot. It is not a Renault Megane RS Trophy R...
I'm not attracted to track driving but I presume you don't use the 6th gear in a race...

 

[CTR1633FK2]

I'm not attracted to trckbdriving but I presume you don't use the 6th gear in a race...

Only needed on the Ring. But not during tourist drives.

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