Road Racing and the Decline of the Manual Transmission

WildScotsRacing wrote: Just a reminder that traditional (torque converter) hydraulic powered automatics are power sappers compared to a manual; a typical traditional automatic uses up an AVERAGE of 25% of the engines' BHP, and the higher the revs climb more the power is consumed by the hydraulic operating system, and the car will always be slower and less efficeint.

And that's why people were ripping the 4-speeds out of cars and converting them to automatic in the 70s.

Er...

A proper automatic is MUCH faster than a manual trans in a straight line. The torque converter is a kind of fluid-drive CVT and multiplies torque when at or under the stall speed, it doesn't just "slip".

The last BGN that I datalogged was upshifting at 5600 but thanks to the torque converter, the revs never dropped much below 4500 either. And there's no lifting for upshifting, something you can't get with a manual trans without a very expensive, maintenance intensive split-slider transmission. It's a seamless wave of power that starts from before the start if you have a transbrake. (Which is even more super effective if you have a turbo that needs spoolin')

Manual transmissions are unneccesary except for driver feel, in this day and age.

Autos have long been the ticket for drag racing and they are becoming the norm in the off road world and the towing world where manuals used to reign.

Knurled wrote:

WildScotsRacing wrote: Just a reminder that traditional (torque converter) hydraulic powered automatics are power sappers compared to a manual; a typical traditional automatic uses up an AVERAGE of 25% of the engines' BHP, and the higher the revs climb more the power is consumed by the hydraulic operating system, and the car will always be slower and less efficeint.

And that's why people were ripping the 4-speeds out of cars and converting them to automatic in the 70s. Er... A proper automatic is MUCH faster than a manual trans in a straight line. The torque converter is a kind of fluid-drive CVT and multiplies torque when at or under the stall speed, it doesn't just "slip". The last BGN that I datalogged was upshifting at 5600 but thanks to the torque converter, the revs never dropped much below 4500 either. And there's no lifting for upshifting, something you can't get with a manual trans without a very expensive, maintenance intensive split-slider transmission. It's a seamless wave of power that starts from before the start if you have a transbrake. (Which is even more super effective if you have a turbo that needs spoolin') Manual transmissions are unneccesary except for driver feel, in this day and age.

I wondered if this would come up. And for drag racing it is absolutely correct that a shift-kitted auto gives quicker ETs than a manual, but not for reasons of WHP output. But this thread's premise is road racing, and traditional hydraulic automatics suck for road racing for several reasons (one of the big ones is the less precise part-throttle power control during cornering), and all else being equal will result in slower lap times; exact opposite of drag racing. Dual clutch trannies don't suffer the vague mid-corner power control that comes from the torque converter.

In reply to WildScotsRacing:

FWIW, not all automatics unlock in the situation you point out. For that matter, modern autos lock more often than not- for efficiency's sake. Once locked, there's a small amount of hydraulic pumping, but the gears are as efficient as a manual box.

iadr wrote:

alfadriver wrote: In reply to WildScotsRacing: FWIW, not all automatics unlock in the situation you point out. For that matter, modern autos lock more often than not- for efficiency's sake. Once locked, there's a small amount of hydraulic pumping, but the gears are as efficient as a manual box.

*nod* Mazda advertise their "Skyactiv" transmission with its tiny converter- no larger in diameter than the gear train, is locked 88% of an average driving cycle.

Fair enough, guys. But there must be a reason all of the uber high power sports cars are dual clutch...

In reply to WildScotsRacing:

Sure there is. Nobody wants to shift on their own.

I personally hate those boxes. Drive like crap.

In reply to alfadriver:

Actually, I meant as opposed to hydraulic torque converter automatics.

My seven year old just drove for the first time, using a clutch. Now, he never got out of first gear, but he didn't stall either. If he can do it...

Part of the problem is a real lack of mechanical skill even by some racing enthusiast's. I've explained to many how to swap a Manual transmission onto automatic cars.. To the best of my knowledge no one has taken me up. It's not difficult, although it is harder than putting on a pair of shock absorbers or changing brake pads..

It's also easy to buy expensive kits that do all the scrounging and parts hunting but even those are far from perfect. If you can rebuild an engine properly you can adapt a transmission.
My point is few people are that willing to buck the norm and learn how to do stuff.

It's very common in the RX-7 community, to the point where we tried to talk one guy down from converting an early '78 build Spark Yellow car. Spark Yellow '78 build with an automatic is unheard-of rare and to quote Indiana Jones, belongs in a museum.

And then there are the longitudinal Acuras... I was there for some of the ordeal where Da Boss's brother converted his newly-acquired Legend (with bad automatic) to 6-speed. Very GRM of him, got himself a black on black V6 6-speed for half the going rate. But it was an ordeal, since Honda made the floorpan and firewall different for automatic and manual units. Spacers and adaptor brackets had to be made for the trans mounting and the pedal box. And then there was the time he swapped in a 3.5RL's engine which required even more shenaniganry.

The VW DSGs seem to be hit or miss. I've driven them with 80k where they had annoying lags and such in parking maneuvers, I have also driven them with 200k where they were flawless to the point where it never brought attention to itself. So in that respect it is just like any other VW item, sometimes you get a good one that lasts forever and sometimes you get a POS. I've yet to identify an owner characteristic so it's probably the car.

That said, I would still rather have a torque converter than a DSG. DSGs use clutches, which are either engaged or slipping. Torque converters multiply torque below their stall speed, they don't just slip. This is an enormous advantage.

The downside is that one needs a hydraulic pump to keep the bands/clutches in place. This is where I'd like to see a DSG type transmission that uses a torque converter and splined clutches. Hydraulic pressure is only required for shifting and engaging the clutch packs, once fully engaged the clutch packs spline-in and require no maintenance pressure. (I'm thinking of the 4.5" circle track clutches for this design). You'd basically only need hydraulic pressure to engage the torque converter clutch.

In reply to Knurled: I should have been more clear.. To me the daily driver has whatever it has.. Auto or manual.. A good daily driver needs a minimum of care and attention.. endures bumper to bumper freeway parking lots and is used as little as possible until the race car is ready..

A race car starts as a collection of parts and becomes a real car with long thrashes at night in the garage.. Not something you hire done..

WildScotsRacing wrote: In reply to alfadriver: Actually, I meant as opposed to hydraulic torque converter automatics.

Image. Being that 99% of owners of the exotic cars can't even approach what the cars are capable of, the non-hydraulic systems offer the owner an image of a race car. Those cars are 100% about image and what they project of you to the world.

The 1% who race them, well...

So, to throw another slight curveball at the normal auto trans for road racing duty, there's the issue of needing pressure to shift. When you are not on the gas, no pressure is built, therefore no shift.

Even if you have a custom program or something, you may be able to ask the trans to shift but it may not be able to until you get back on the power. Not great for road racing.

In reply to alfadriver:

Exactly... exotic cars are never about performance, they are automotive jewelry.

I understand that a lot of F1 fans don't care about the racing so much as the technology involved. So in that respect I can understand why some people would go ga-ga over some exotic having all of the latest buzzwords. I can't relate to it but I can understand it.

This is as opposed to NASCAR, where many of the fans are pissed off that they are running EFI, because they want to see racing where they are running pushrod V8s with carburetors just like they can find in the junkards when they were kids 30-40 years ago. I can't relate to that either, but I can understand it...

Robbie wrote: So, to throw another slight curveball at the normal auto trans for road racing duty, there's the issue of needing pressure to shift. When you are not on the gas, no pressure is built, therefore no shift. Even if you have a custom program or something, you may be able to ask the trans to shift but it may not be able to until you get back on the power. Not great for road racing.

The pressure is built by the front pump. If the engine is turning, there's fluid pressure. If there is no fluid pressure, NO gear is engaged, as any "gear" will require hydraulic pressure to force clutchpacks together or bands against drums. This is why automatics have a parking pawl.

In non-electronic transmissions, the shift schedule is determined by the governor, which is nothing more than a spool valve which moves in and out based on output shaft speed (flyweights and springs, just like a mechanical-advance distributor) and either a throttle-position cable or vacuum modulator to determine engine load. Engine load plays against vehicle speed to determine shiftpoints and shift force.

I've only played with GM transmission electronics, but their shift schedule is also TPS/roadspeed based. From observation in my Volvo, it is also TPS based - turning the boost up didn't change shiftpoints any relative to throttle position. But turning the boost up DID cut down on downshifting in traffic because the engine could make more power at lower throttle openings.

Every road-race automatic I've seen (oddly enough, all have been in C4 'Vettes) was manual shift. The main issue with circuit racing and automatics is that they can't see the road ahead. A "dumb" transmission will see you lifting off the throttle to brake and upshift. So you go with a manual valvebody so the driver determines what gear the trans is in. With a ratcheting shifter, you get a poor man's sequential trans.

Interestingly, my Volvo's controller (again, using it since it's the one I'm most intimate with, having lived with it for a while) will NOT upshift when you let off if you have been at WOT for a length of time, or if the throttle position changes too rapidly. It's some crude algorithm that senses that you're braking into a corner and will hold the gear for you. Sometimes it works, sometimes it doesn't. I can "request" a downshift by rapidly smacking the throttle to the floor before accelerating, in the same right-foot motion as I'd use with a double-declutched downshift, so it's not much of a bother.

In reply to Knurled:

This I did not know, thanks!

Andy Neuman wrote: In twenty years we will be pushing for cars that we can still control.

And that's when I'm getting back into motorcycles.

In reply to Robbie:

As long as the engine is running there is pressure.

I will keep my manuals as long as possible. Helps that I only drive old crap.

I've never understood why we can't have motorcycle-style clutched sequentials. Lighter than an auto/DCT, potential for 9 gears or whatever you want, none of the inefficiency of the others.

I realize the clutch is too scary for most mini-van customers, but why not on Miatas and Vipers?

DaewooOfDeath wrote: I've never understood why we can't have motorcycle-style clutched sequentials. Lighter than an auto/DCT, potential for 9 gears or whatever you want, none of the inefficiency of the others. I realize the clutch is too scary for most mini-van customers, but why not on Miatas and Vipers?

From my experiences riding motorcycles, if you stop and have not worked your way down to first or second it can be a pain to get back there from fifth or sixth. There is no skipping gears like an H-pattern. It's hard to rock a car to help run through the gears while stopped.

Yep sequentials are actually a pretty big PITA, their only positive traits are quicker and more foolproof shifting as long as you're going through 1 gear at a time, and having less potential failure points than a robo-manual. I'd only consider a sequential over an H-pattern for dedicated racing use, and I'd pick a robo-manual over a sequential every time just for the simplicity of operation and performance.

H-patterns are on the way out, they're already a bit of a "vintage" option, robo-manuals are just as efficient and perform better, so H-patterns only make sense for budget-conscious driving enthusiasts, who you may recognize as the people who very rarely buy new cars (or swear off the idea entirely).

But transmissions in general are probably on the way out as they're generally not useful on an EV.

irish44j wrote: no, it just means everyone will be "vintage racing" a couple decades from now in really really old Miatas and e30s and whatnot. well, at least me.

You can already put Collector Car Plates on those cars in Wisconsin!!! You're vintage racing now!

DaewooOfDeath wrote: I've never understood why we can't have motorcycle-style clutched sequentials. Lighter than an auto/DCT, potential for 9 gears or whatever you want, none of the inefficiency of the others. I realize the clutch is too scary for most mini-van customers, but why not on Miatas and Vipers?

They don't scale up very well, same reason we don't have chaindrive cars.

I guess we could all stock up on cars from the 80's and 90's and just keep driving those forever?

Correct.