The new Star Mazda racing cars opened their season in Sebring, Florida recently. They are using the new Renesis rotary engines for power and they have a new type of manual transmission that I heard them call "sequential shift".

What it means is that the traditional H-shaped shift pattern is not used. The shift stick is moved forward and backward in a straight line to go from higher-to-lower gears.

I wonder if that is something that Mazda will push down into its production version of the RX-8 any time soon. I think it would be a very cool change.

The race drivers were all raving about the car's performance and handeling. The pole sitter in this first race would have been good enough to place 12th in starting position of the big Sebring race.

 

Sounds nice....but i would never own a car with the sequential gearbox....not my style, the traditional H-pattern cannot be beaten, you do probably get quicker shifts with the SG though?

 

The Toyota MR-2, BMW M3, Audi something other and some Maseratis and Ferraris, Swatch Car (can't remember real name) and probably a few others already have sequential gearboxes.

The street versions of sequential gearboxes I have driven either shift slowly or are not smooth enough when putzing around. Plus, I like being able to modulate the clutch. I'm sure in a few years these sequentials for the street will be perfected.

 

All those cars you mentioned have computer-controlled "semi-automatic" systems with no clutch pedal. I believe the Star Mazda cars have a racing-style sequential gearbox with a normal driver-operated clutch. (Someone please correct me if I'm wrong.)

 

I think I agree(?). How would you go from say 3rd to 5th or 6th directly... just keep hitting the lever. Or what about 6 to 3rd downshift?

Sound wierd and awkward if that is the way they work. Too slow and cumbersome. Or am I wrong?

 

Len is closest to right. The racing sequential gearboxes are most like motorcycle gearboxes, and there are several reasons why that design will not be used for production street cars.

The Ferrari F1, BMW SMG, etc. style of semi-manual gearbox that are commonly called 'sequential' gearboxes (like the 'S' in BMW's "SMG") are not sequential gearboxes at all - they are traditional synchromesh gearboxes (just like the versions with a H shift pattern), except the computer controls the clutch and shifting. While they could easily be shifted non-sequentially (ie 5 to 2 downshift), the computers are only programmed to shift up or down 1 gear per paddle click, so in effect they are sequential - but mechanically, they are very different from a racing sequential gearbox.

As I mentioned, you will not see a racing sequential gearbox in a production street car, but you WILL see the SMG style semi-manual gearbox offered in the RX-8 for the 2006 model year.

Regards,
Gordon

 

The Audi TT V6 has something closer to a "real" sequential--basically, there are two sets of gears stacked concentrically: 1-3-5 and 2-4-6. When you're in first, the computer pre-engages second gear on the other spindle. Hit the paddle, and it switches over while readying third gear on the original spindle. No slushy torque converter, no hesitation. Of course, you can't slip the clutch, and can't dump it at 6k, but overall it's just awesome.

There's a great write-up on it in the last Sport Compact Car, with a lot more technical accuracy and detail than the EXTREMELY rough summary I provided above.

Peace
policy

 

the smg gearbox is a true sequential gearbox. it has 11 settings- 5 'automatic' and 6 manual. 1 is the slowest shift, 5 is the fastest. in these settings it wont let you kill your engine by accidentally going from 5th to 2nd at 130mph. however, in the manual 6 it is a true sequential, and you can blow your engine all you want. the shifts are something like 0.04 sec quick, and if you go from 5th to 2nd at 130mph it will let you...and promptly blow up.
while i havent had the pleasure of driving it yet, my dad (whos been offered track instructor jobs) has taken me out a few times and i can tell that its an awesome piece of equipment. as great as my 8s short-throw feels, id much rather have paddles.

 

what about the Paddle shifters, like on some super-cars and F1's, (Enzo, Buggatti Veyron, f1 cars, some rally cars) etc...

The Buggatti Veyron is made to be the fastest car, faster than the Saleen S7(and I think it might be)...with 7 GEARS(!!!)...+220mph....crazy fast....
here's my show:

 

the exterior

 

Here's what I think SG shifting is:

 

most (if not all) have paddles, as well as the floor-mounted stick and either can be used.

and seven gears is rediculous. personally, id rather have my 8 be a five-speed

 

I think a true manual sequential shift gearbox (w/ clutch) would be awesome in a car! Shifting multiple gears is simply a matter of multiple clicks. If you've ever ridden a motorcycle you know what it's like already. Plus computer assited clutching and push button shifting once rolling could be an added benefit for those times when you're stuck in traffic and don't feel like shifting.

It would seem to me that a true sequential shifting gearbox would be simpler and more economical than the traditional "H" gearbox by eliminating the need to allow shifting from one gear into any other gear.

 

Its called Dual-Tronic

Developed by the company I work for.

 

I will always love my clucth pedal and shifter directly into the tranny....

 

word

though i could imagine hittin the "buttons" could be fun in its own way, IMHO, nothing will ever be able to match the "oneness" provided my a short-throw and a clutch pedal
________
Wendie 99

 

Troy - you aren't paying attention! All the recent tests say that the new Audi/VW DSG sequential gearbox is the best (and the fastest shifting). Ferrari and BMW have been beaten in the gearbox design wars (for now, at least).

Regards,
Gordon

 

My question is - Can we fit those sequential gearboxes in our RX-8s? In other words switch the MT/AT for the SMG as an Aftermarket modification?

 

No. The SMGs are very highly integrated with the engine computer (ECU, or PCM to Mazda). However, in a year and a half or so, you could trade your 2004 RX-8 in on a 2006 RX-8 with the factory optional SMG!

Regards,
Gordon