I know this is kind of a stupid question but I've wondered about this for awhile. Why are manual transmission cars generally faster than autos? (This is assuming same hp, make, model, etc.). Doesn't an auto shift faster than a person can?

A manual Boxster S is way faster than a tip Boxster S. Why?

Thanks for helping the feeble minded (me).

 

Usually gearing in auto transmissions are not as good as manuals. the 944 series cars were a four speed auto verses a five speed manual so the gears would be taller in the automatic. Auto's are also (generally speaking) not as efficient as manuals and lose more power.

 

I think it is because an automatic transmission has a higher power loss (more moving parts) than a manual. therfore the same HP is at the flywheel, just not at the rear wheels.

 

you just beat me!

 

Yea, i believe most of the powerloss occurs in the torque tube/converter on the automatics. Gear ratios can be set farther apart on a 5-speed do to the extra gear (or two in the 944/924 automatics case). Also i believe it helps to be able to shift right in the powerband on the manuals. I wish i had a manual...

 

i thought it was a 3 speed auto?? i could be wrong but anyone else know??

 

Im pretty sure all the 944/924s are all 3 speed autos and they also have no overdrive. I dislike running at 3700rpm at 75mph on the expressway...oh well. My centerconsole vibrates alot, i usually take out the ashtray to stop it.

 

yep, 3 spd auto's. Imagine a manual 944 NA with only 2nd, 3rd, and 5th gear . . . that's what the auto's feel like

 

Manual by far. The only thing to beat a manual, assuming like gear ratios, is a Tiptronic type of setup. That would totally eliminate clutch time.

944 autos are threes speeds. I'm think that the 928 came in both 3 and 4 speed models.

 

red9four4

You may be right about the three speed thing. It's been about ten years since I drove one with an auto.

 

1) Gear ratios. Typically more and better spacing (closer) in manual

2) More power to the ground. Auto typically have fuild coupling that is not as efficient as a clutch to transmit power so less power reaches the ground

3) Not all auto's can shift a redline

4) Manual changes are actually quite fast (Ferrari 360 Modena has F1 paddle shift and trad manual, they say the trad manual has faster gear changes with pro race drivers. Avg drivers may not be, but pros are)

5) Downshift and control. Manuals provide much better engine control. Ie you know where it downshifts/upshifts and when. Much faster on the track. Newer Tiptronic type systems are good, but still not as fast or as much control as with proper manual.

 

BTW: there are automatics out there that are just as fast in shifting. Two come to mind:

The Mercedes-Benz automatic (touch-shift in MB-speak) does the same 0-60 as the manual counterpart in the SLK-230 Kompressor. Keep in mind, the MB auto tranny is a 5-speed auto with a 'tip-tronic' like shifting available.

The Ferrari paddle-shifter F1-style shifters are far superior than the manual gated shifters.

And I agree with the above statements that a torque converter robs the power: IMHO, it is the biggest reason that most autos are slower than the same car with a manual tranny.

So, why is the Ferrari F1 shifter faster? Simple: it is a race bred system: I believe there is no torque converter in that car. Why is the Benz auto the same as the manual? Well, IMO, it's a marketing thing. Most Benz owners want an auto tranny, but also want to have the 'best, fastest, mostest' the car has to offer. By making an auto tranny that is just as fast as a manual, Mercedes owners can have their cake and eat it too!

Just my $0.42,
-Z.

 

I remember hearing that at Daytona the 360 guys were compaining about losing time to the GT3RS due to F1 Paddle shift taking longer. Sure the F1 is race breed system, but it is not up to full race system built and programed to race standards. I'd agree that it is better for the majority of folks, but I think a pro race driver can make faster upshifts in a race spec manual gearbox and that was a complaint about the system at Daytona 24 hrs this year.

 

M758: Point taken. I guess when I get to the level of the Daytona 24-hour driver's, I can start complaining about how slow the F1 paddle shifters are!!

-Z.

 

I don't think a human can outshift a paddle shifter. I remember seeing numbers for it somewhere, and the paddle shifter can disengage, shift, and reengage in about the same time that it takes a normal clutch pedal to come back as the driver lifts his foot. That doesn't even include depressing the clutch and moving the shifter.
A race car clutch could be a different story though.