20 replies to this topic

[Jhope]

Here's a little something I dug up while resarching the Williams FW20. I was always under the impression that for the longest time, Formula One cars used longitudinal gearboxes. But when reading up on the 1998 FW20, Patrick Head made a comment that threw my beliefs in to the trash can.

The gearbox is still a transverse unit but it is also new, although it has the same basic layout as the one we used last year. There are lots of new details and I must say it looks to be a very promising unit. Lots of people seem to want to change to longitudinal gearboxes but I doubt that having a longitudinal gearbox rather than a transverse one is going to be a race-winning factor. And you must remember that 16 of the 17 races last year were won by transverse gearboxes."

The questions I have for you guru's is, when was the longitudinal gearbox adopted by all teams on the grid? And what advantages do longitudinal gearboxes provide, aside from aerodynamic, over transverse gearboxes? And who was the winner of a race in 1997, who's car used a longitudinal gearbox?

I might totally be wrong here, and can be confusing longitudinal with transverse, or vice verca, but i don't think I am.

Longitudinal? <-----engine-- rear wing------>

Engine
Transverse? <----L.R.Wheel----R.R.Wheel-->
R.Wing

[Chevy II Nova]

Reading Steve Matchett's book I recall him mentioning that around the time he was trying to get into F1 (1990ish?) he talked with the Onyx guy about the pros/cons of the two methods. That led me to believe that around 1990 they were coming to a finalised method..

[Wuzak]

Races were won by Williams Renault (8 - JV 7, HHF 1), Ferrari (5 - MS), McLaren Mercedes (3 - DC 2, MH 1), and Benetton Renault (1 - GB). So, if Head is correct then the one would be Benetton Renault, as I doubt anybody rearranged their gearbox during the season.

I think that the main difference between the two layouts is in weight balance.

Ferrari originally went to the transverse layout becuase of the length of their V12 engines (both in the '70s and the '90s), in order to keep the weight between the wheels and keep the wheelbase down.

This was adopted by most of the teams during the years.

The big change in 1998 was in relation to the width of the cars and the grooved tyres. Maybe this is what convinced the teams that the longitudinal layout was a better solution.

[J. Edlund]

I have to agree that this would mainly be a balance issue, which is also the main reason for that the teams are using gearboxes placed before the rear axle rather than after.

I also wonder when McLaren will start using their carbon fibre gear case, they didn't use it in Australia because of reliability issues, also, is there any other team that has one except Arrows?

[Jhope]

Interesting replies so far. Appreciated alot.

When you guys mention balance as an issue, do you also mean weight distribution? Where using a longitudinal gearbox places most of the weight in front of the rear wheel axle?

[perfectelise]

Or all the weight in some cases AGAIN

[Jhope]

That's the Williams gearbox if I'm not mistaken.

[RX-7]

Originally posted by perfectelise
Or all the weight in some cases AGAIN

Man! That is beautiful! I never get tired of seeing great shots like this.

[Chevy II Nova]

Originally posted by Jhope
That's the Williams gearbox if I'm not mistaken.

Toyota if I remember right.

[mrman_3k]

Sorry for the newb question, but what is the difference between a transverse and longitudinal gearbox?

[Timstr11]

According to this article by Peter Wright, by the 1997 season, only Ferrari, Williams and Prost retained the transverse gearbox layouts (Prost were using the ex-Benetton box).
http://www.grandprix...ft/ft00264.html

Originally posted by J. Edlund
I also wonder when McLaren will start using their carbon fibre gear case, they didn't use it in Australia because of reliability issues, also, is there any other team that has one except Arrows?

AFAIK BAR is currently the only team on the grid using a CF case.

[desmo]

A bit from Peter Wright's book "Formula 1 Technology" on the question of transverse vs longitudinal gearboxes in F1:

"Until 1975, when Ferrari first ran a transverse gearbox and, in so doing, turned the drive through 90 degrees before the gear cluster instead of after it, the standard layout positioned the gears behind the final drive. This layout afforded the ability to change any of the 5 or 6 ratios in approximately 30 minutes, The disadvantage of this layout was the mass of the geatrs behind the rear axle.

When the regulations moved the driver backward to prevent his feet from being forward of the front axle, it became difficult to achieve the forward CG the tires demanded. This, coupled with an increasing awareness of the influence of the yaw moment of inertia, caused other designers to follow Ferrari's lead, placing the transverse gear cluster forward of the final drive.

In the last 5 years [written 2001], again lead by Ferrari, all teams have reverted to longitudinal gearboxes, with the gears located forward of the final drive. This arrangement provides the current optimum tradeoff among underbody aero, internal airflow, mass distribution and weight, time to change ratios, structural stiffness, overall length, transmission efficiency, and reliability.

The original longitudinal layout, with gears placed behind the final drive, lent itself naturally to a two-speed reduction from the 13,000 rpm of the engines in the 1970s to the approximate 2500 rpm necessary at the wheels, equivalent to 320 kph. One reason for the change to a transverse layout was the need to introduce an additional speed reduction stage, to accomodate the ever increasing engine rpm- up to 18,000+. In this arrangement the input shaft drives the gears directly (1st stage), which incidentally results in high gear tooth speeds but lower torque and hence tooth loads, and the output shaft drives a bevel (2nd stage and 90 degree direction change) which then drives a spur gear final drive (3rd stage). An alternative arrangement swaps the 2nd and 3rd stages, with the output shaft of the gears driving a step-down spur gear, which drives the bevel final drive. This arrangement restricts the options in placing the final drive relative to the output shaft of the gears."

[J. Edlund]

Originally posted by mrman_3k
Sorry for the newb question, but what is the difference between a transverse and longitudinal gearbox?

All F1 cars are using what's called a transaxle gearbox, this gearbox can then be transverse or longitudinal.


This is what's called a transverse transaxle, the axles for the gears are placed "transverse" which makes the gearbox short but wide.


This is a in line transaxle, the axles for the gears are placed "in line", this makes the gearbox longer but more narrow. In this case the gearbox is placed after the differantial but it can also be placed before.

A transaxle gearbox can be connected to the engine directly or with a propshaft. When the gearbox is placed before the diff this will take up more length but there will be no weight behind the rear axle. With the gearbox behind the diff it will take up less length but there will be weight behind the rear axle, it's also easier to replace the gearbox.

[Jhope]

Originally posted by Jhope
That's the Williams gearbox if I'm not mistaken.

Maybe I was wrong....






Interesting to point out. The forward suspension pickup points for the Williams are on the gearbox (standard practice I assume), whereas the McLaren's seem to be on the engine block. Any reason for the McLaren philosophy? Any advantages? What are the disadvantages?

And, wow, look how small that Williams gearbox is. I don't think I've seen one that small since Ferrari started the trend of minimising the size of the transmission.

[Jhope]

This may be a first, but if it's not, here's a picture of the B-A-R Carbon Fibre Gearbox.

[scarbs]

This is certainly the first shot I’ve seen of the gearbox from this angle. Its a full carbon gearbox case, judging by the closing plate on the front of the gear cluster, the gear cluster, shafts and bearings are mounted on metallic bulkheads and not carbon, what exact material is up for debate (Ti, Al or perhaps MMC) Geoff Willis wouldn’t tell me and jokingly claimed he didn’t even know that sort of technical stuff. The cross section of the front face of the case is typical for F1, where the lower mounts are as wide as the sump and the upper mounts are at the widest part of the Vee (i.e the bottom of the cam boxes). This very wide top section makes the upper wishbone seem very short which perhaps explains the choice of a spherical joint used over of a flexure. Damper and torsion bar layout seems to follow on from the 2003 car, but with more elegant rockers.
I don’t think enough credit has gone to BAR for getting this development so race reliable over the winter, McLaren are still having problems with theirs according to claims. I seem to remember hydraulics and transmission problems (albeit some control systemrelated) were a weak spot of most previous BARs.

Scarbs…

[Jhope]

I was just thinking. Couldn't a carbon gearbox be incorperated into the rear crash structure, thus making it a stiffer solid one pice unit?

[scarbs]

I doubt that would be of any use. The rear crash structure fixes the rear of the diff casing.
Often no suspension elements are mounted to the crash structure, limiting any gains in making the assembly stiffer. The rear toe arm is mounted to the rear diff cover but so far forward that attaching it to the crash structure may not offer any benefit.
Also, it would be impractical to make the rear half of the diff cover as large as a heavy rear impact structure. When the gearboxes are being shipped around or built up at the factory.

[Greg Locock]

"Couldn't a carbon gearbox be incorperated into the rear crash structure, thus making it a stiffer solid one pice unit?"

Not really. Gearboxes, diffs and transaxles have to be as stiff as you can make them - to resist the very high forces in them and maintain alignment of the gears. It is generally a good idea to keep the engine (etc) separate from the crash structure - ideally you try and make sure that they hit the barrier first, so you don't waste any of your crush system decelerating the heavy stuff that doesn't matter.

[Powersteer]

Excellent pictures. I don't see pellerin's suspension in any of those pictures or any picture so far this season. Last i saw it was on last years Jag. Seems now the teams are using radio control car style torsion bar with a spring damper unit connecting left to right.

[perfectelise]

The drive shaft looks a strange colour.