auto vs. manual m3

[m3f_m3_858_123dcfc955]

i blew my 97 auto tranny and had a 99 tranny put in the other day, did couple of other things to the car (fuel filter, plugs, etc..). it was me and my gf in my m3 and my friend with 2005 civic behind, so we get on a freeway i decide to test my tranny so hit 125-130 and while doing that i flew by a yellow 2 door m3, after i found out that my tranny is ok i slowed down to 65-70 and just cruising home minding my own business, now that m3 comes up to me and lines up beside me on the freeway, from what i saw it was lowered and definitely had intake possibly chip, we both looked at eachother and i floored it, he downshifted, we both went for it, i instantly started gaining on him 1,2,3,4 car lengths, when he downshifted his whole car "jumped" looked like it had some balls, my friend told me in the civic behind us that he heard the yellow m3 churp tires, i though i was gonna get smoked since i'm auto, but surprisingly i gained 4 car lengths on him by around 130mph, then i let off, we both slowed down to the speed limit and went at it again, i missed my exit but it was worth it, same thing again, around 4 car length break in between us.. he also had a girl in his car so it was pretty much a fair race except the fact that i maybe have 2 mods on him (pulleys and exhaust), but my car is auto.. the only explanation to this is the gearing in my car vs. gearing in his car..



i've raced my friend's manual m3 off the line and he pulled on me by about a car length, we raced 0-80.. that was back when my tranny was slipping..



any ideas? is the 99 auto tranny any different then 97? is it the gearing? pulleys and exhaust doesn't make that much of a difference i don't think, right?

[m3f_Sirius_880bd69485]

Unlike the auto, he can control how the clutch is engaged. The auto tranny tries to smooth out the shifts, even when you call for agressiveness.



With the manual, you have alot more control over the transmission and how you engage the gears.



Oh, the gearing on the two transmissons are different. And actually, I think the E36 came with a 4 speed auto. Maybe thats just the non-M versions, I would have to double check that.

[m3f_mighty-dog_11395d17be]

A manual M3 with a skilled driver should have an edge, but I'd expect not much. Someone who goofs or just takes longer to shift can give up significant ground and then the auto would gain an advantage.



I have owned both auto and manual M3s. The manual-equipped car feels a bit spunkier than the auto. For my skill, I'd guess a fairly even race versus myself in either car.



It's well known that manuals are faster in the sprint to 60. Typical published figures are ~6.6s with auto and ~5.8 with manual. There's some +/- in those figures.



I don't care to abuse my car thus I forego the theatrics of a best-effort launch from a stop. There's no theatric in stomping the gas from a stop in an auto. There's slush time when power is being transferred to the torque converter and not to the ground (auto is more slouch from a stop). Head to head with me at the wheel of each car, I'd expect to come out fairly equal in a sprint to 60 just b/c I'm not fully hammering the manual vehicle.



In a rolling-start race, I'd say driver of the manual car will determine the outcome. My M3 with auto had spunk at speed, and I often controlled the gears with the shifter instead of letting the car decide the gear.



We shouldn't forget to consider condition of a particular vehicle. One may have more wear or need a tune-up.



Data:

Manual trans M3s weigh 3175 lbs.

Auto trans M3s weigh 3241 lbs.



Both come with engines with 240hp. Apparently transmission choice determines a slightly differently tuned engine. Max torque with manual is 236 lb-ft/min @ 3800rpm. It is 225 lb-ft/min @3800rpm with auto.



Data comes from technical section of the original BMW sales brochure.

[m3f_Brent_Vino]

if you put 4 cars onto this guy, he wasnt driving an M3.

[m3f_astan100_7ef66fbe89]

Yeah 4 car lengths is a TON...so he was either in the wrong gear...or something. I don't that any NA mods would put another M3 4 car lengths in front. I really couldn't tell you though...

[m3f_SG_M3_d1201712b5]

, we both looked at eachother and i floored it, he downshifted, we both went for it, i instantly started gaining on him 1,2,3,4 car lengths,



So you floored it, the car kicked down obviously. He had to let off the gas, clutch in, select the next gear down, clutch back in, WOT.



Sounds like he wasn't ready, in the correct gear, you just pulled away. Both cars have about the same power, it would be very hard for him to catch and pass you with that much of jump.

[m3f_m3_858_123dcfc955]

great replies, to clarify somethings auto m3 came with 5 gears and different rear diff than the manual, longer gearing, sgM3 your response was i think the reason for the win, i had about a second of advantage on the race from the start, and that played a role, also i think the most part was the fact that he had to shift into 5th gear when i was still in the power range of 4th, so at the given speed and rpm my engine was producing more power and stayed in the powerband longer since i have longer gears.. anyhow, i would take manual m3 over auto any day, i just thought it was kinda cool that i pulled on a manual and wanted to share the story with u guys.. and yeah 0-60 sprint auto is slower because of a bit of a power loss through the torque converter..

[m3f_Serious_eeb8859403]

a friend of mine witha dakar 98. we are almost dead even in a race. even a .5 second jump from either car will result in a car lenght for whoever jumps.

[m3f_ICE99M3_fd108332c5]

I know for a fact that the difference between the auto and manual trannys for the m3 is pretty big... I have a 99 M3 coupe with a 5-speed and my dad has a 99 M3 convertible with the auto...We drag raced both being stock and my car won by over a second

[m3f_Sirius_880bd69485]

You need to compare two converts, or two coupes. Comparing a coupe and a convert isn't the best because converts are usually slower from the get go.

[m3f_95RogueM3]

and stayed in the powerband longer since i have longer gears..



You have shorter gears...not longer/taller gears in the differential 3.38 as opposed to a 3.15 or a 3.23 in manual m3s



I am not sure about the tranny gears..but I would imagine if its a 5 speed than it cant be that different from a 5-speed manual.



-Richard

[m3f_m3_858_123dcfc955]

i think i have longer gears since i can do 160mph at only 5200 rpms :nixweiss:

[m3f_95RogueM3]

i think i have longer gears since i can do 160mph at only 5200 rpms :nixweiss:



You mean transmission gearing?



I assume that what you mean as it is well known that 97+ autos have a 3.38 rear diff gearing and all manuals are equipped with either a 3.15 or a 3.23 rear diff.



I dont know the ratios on each tranny gear....though 5th is 1:1 on the manuals



-Richard

[m3f_SG_M3_d1201712b5]

Auto

3.67 (1), 2.00 (2), 1.41 (3), 1.00 (4), .74 (5)



Manual

4.20 (1), 2.49 (2), 1.66 (3), 1.24 (4), 1.00 (5)



The auto is much like any american auto, wide gears, 4th being 1:1.

[m3f_JustASedan]

i know my auto sedan kept taking a manual coupe at the track unless the guy just really really didn't know how to drive... it was rather amusing