different rpms between auto and 5spd

[neoP5]

like i said in my last thread i have a 2003.5 with the hole tiptronic thing going on and i was wondering what rpm a 5 spd is sittin at doing 80mph? mine is right at 3200 rpm. i know its a weird question but just something i thought of sittin here LOL (braindead

 

[jersey_emt]

Somewhere around 4K..don't know the exact #

 

[uclap5]

i think at 80 its around 3.8

they are going to be differnt since they have different gear ratios.

 

[Replica]

Yep, me too. 80mph is about 3700-3800rpm.

 

[Khoifather]

I notice then when I shift with the auto stick, it drops about 1000RPM. How much does it drop when you guys shift with a manual?

 

[Replica]

I notice then when I shift with the auto stick, it drops about 1000RPM. How much does it drop when you guys shift with a manual?

Depends on the gear. 4th to 5th is 1,000 rpm. 5th to 3rd is like 2500 or 3000rpm.

 

[tttP5]

drop in RPM in manual shifting really depends on how long you hold the clutch down in neutral. and RPM is goverened by speed..... so therefore if you are in neutral longer then drop in RPM is going to be greater because of more speed lost.

anyways i thought that the highest gear in an auto is 4th gear.

what i don't understand is how come an auto gets worse gas mileage if its RPMs are lower than the manual at the same speed?

 

[bradman]

Takes more work to get the car moving since RPMs are lower. For example, if you jumped from 1st to 4th, even with your pedal to the metal, you woudln't accellerate that quick...all the while sucking gas.

That's my theory anyways.

 

[akhilleus]

I do about 3.2k @70 so maybe 3.5K @ 80-90 depending on the gear. i have a basic auto... no shiftronic. I can do 70+ at 6k in 2nd though. so probably 3rd for the above #'s and lower for 4th

 

[neoP5]

i can hit around 110 right at 7000 rpm in third

 

[Mach 3.5 Turbo]

Automatics are inefficient for a variety of reasons, but I'll hit the main ones here. Mainly, there is no direct connection between the engine and the transmission like in a clutch until you get into 4th gear. It'd take a couple pages to explain how the torque converer works, so I'll let you figure that one out on your own. The other big reason is that there are fewer gears in an automatic, so the transmission isn't as close to the optimum gear ratio as much as in a stick shift. That's why a CVT is fairly efficient. It is always in the right gear ratio, since it varies infinitely. CVTs are still less efficient than a stick though, since they still use a torque converter (no direct connection). I work for a clutch, torque converter, and CVT manufacturer so shoot me any questions you all have.

 

[jersey_emt]

i can hit around 110 right at 7000 rpm in third

3rd gear tops out just around 90 in the manuals

 

[akhilleus]

i can do about 100-110 in third. but it sucks not having a fifth gear I will defend the auto to a degree but i still wanted a manual. the torque doesnt come in as quickly on an auto but it is consistent. there are options like new torque convertors, recalibrated valve bodies and other components. however precise downshifting is more difficult with the auto. oh well