96ss#80

Im posing this question to people that may have more technical insight than myself. Why haven't any of the hi perforce car manufactures installed a sequential gear box? I know If there were something like that on the market it would catch my eye! They are used in rally cars and motorcycles with great success. They shift faster than the typical H pattern type shifters. I have wondered this for a really long time... Everyone is always taking dual clutch PDK SMG or what ever BMW is using now. Im talking 3 pedals not some computer operated clutch deal... A regular manual transmission only difference being it's a sequential shift instead of H.

WelderGuy

The mechanism required for sequential shifting probably lacks the long term reliability and ease of use manufacturers want for a production car.

jamesw95

And they are noisy and clanky and expensive. I think they would be fun though.

JerryU

The last thing I would like for a high torque engine like the LT1 is to have to go through all the gears in sequence! This is not a high rpm, low power at low rpm engine. The C7 has 3 overdrive gears. Even if you go through the first few gears, no need to use all of the rest. For example when accelerating on a highway ramp in 4th gear at 2600 rpm you're at 60 mph, might as well continue to a modest 3300 rpm to 75 mph and shift to 7th. No need for 5th and 6th. In fact you could stay in 3rd and accelerate more quickly to 4700 rpm (1900 rpm from red line) and be at 75 mph then shift to 7th. On an off ramp as I am breaking I slow and downshift to 4th using rev match and am ready for the speed at the interesting road. On the rural roads around where I live, I frequently go from 3rd directly to 5th, where I will drive. Just my thought.
Racings another story; closely spaced gears for a peaky torque engine, but the straight cut spur gears would make a radio useless!

Curahee

Isn't the A6/A8 tranny essentially a sequential box when in manual mode?
Minus the clutch, of course.

bigjku

I belive even in manual mode you can make it skip gears. Holding on the downshit paddle should make it shift to the lowest safe gear directly instead of sequentially.

WelderGuy

Also, there's no torque converter in a sequential shift transmission.

mjw930

Ferrari, BMW and Aston have all had SMG transmissions in their cars and every one of them were great on the track and horrible on the street. Granted, they were automanuals with computer controlled clutches but regardless they were not ideal for road use.

The C7.R uses a sequential box with paddle shifters and a clutch. Again, great for the track, not so good on the road. The $10k+ price tag doesn't help.

OnPoint

Probably because a good one, like the Hollinger (I got to experience one of those in a C6 Z once, pretty amazing) cost like 35k. Plus the maintenance.

stevebz06

I have long wondered why a sequential box can't be done in a car. Motorcycle shifters are essentially a sequential shifter and you can buy an entire motorcycle for what you would pay for just the sequential gear box for a car. If skipping gears is that important, declutch, shift a couple of gears, then let the clutch out.

It would make missed shifts more of a rarity and blown engines from selecting a lower gear than intended almost an impossibility.

mittens

http://www.s1sequential.com/

The bolt on sequential shift conversion changes the standard H pattern gear box to sequential action allowing you to simply push forwards for a down shift and pull back for up-shifts eliminating the chance of missing the 2-3 and 4-5 shifts .

This conversion simply bolts on there is no need to machine of change any internal parts of the gearbox .

The unit has been specifically designed to work with a syncro gearbox ( but will work just as well with dog gear conversions ) and does not need any form of electric assistance to get the job done there for it is still the driver 100% in control and getting all of the feel of the shift through the lever . This was an important part of the design as I think most owners choose the manual gearbox for that feeling of being in total control of the car .

Gear selection is simple as pull back to change up gears push forwards to change down , neutral is half way between all gears like normal and reverse is selected by putting the gearbox in neutral pulling the lever then pushing the lever forwards to engage the gear .

canyon vette

This shifter still requires the use of the clutch. No real benefit in gear change speed if you're left foot is still involved.

redzone

Sure there is a benefit. With a sequential you move the shifter an inch or less each time as opposed to the 4-5 inches for an H pattern.

This is if the shifter itself acts like the one in a Hollinger.

C7Joy

But that would kill off the CAGS!

Woodson

Not even close.

canyon vette

Correct about shorter shifter through, but the clutch foot can't keep up with hand movement speed and coordination in exact continuous fast shifting.

Sequential and dog ring gear boxes are faster at shifting and a great benefit in racing, because they don't require race driver to cordenate hand and foot movements by removing the need for clutch depression and the extra time it takes.

So there is no real benefit at all with street car's.

thrilled

I had read I guess it's been 5-10 years ago the BMW M3 had the sequential transmission.
I understand they don't have it now.I guess people didn't like it.I'd sure like to give it A try.

chuntington101

True sequential boxes are great for racing with clutch less up and down shifts. However on the road they are utterly ****! Clunky and difficult to operate at light engine loads and when not hammered home. Even the electronic sequential boxes, see mark 1 Aston Martin vantage, are crap and they have propped torque management throughout the shift.

DSG style dual clutch boxes offer all the benefits of a sequential with the smoothness that the sequential a just could never have. They are astonishing and I hope GM get on the bandwagon and soon!!!!