Can the four speed auto reach the same top speed as the five speed gearbox?

[Bad_Tuscani]

Originally Posted by tibby01

i dont really know why you are so concerned about top speed though, it has nothing to do with any kind of racing.

It just sounds better when u say "i can kick your ass in the 1/4 mile & TOP END"...........u know, just kinda twist the knife, dump salt on the wound, pick the scab, etc. etc. etc.........more bragging rights plain and simple

[Adam_Hunsicker]

Originally Posted by tibby01

not many people tested the 4cylinder because it wasnt the big import favorite. i would say that the auto cant go as fast as the manual, simply because there are more gears in the 5speed. i dont really know why you are so concerned about top speed though, it has nothing to do with any kind of racing.

When dealing with top speed the number of gears isn't going to matter.... the final gear ratio of the top gear in both transmissions is going to make the difference.... I don't care if you're driving a 20 speed... that isn't going to make it faster, it's going to make you shift more often... I haven't been able to locate the specs on final gear ratio for the two trannies but I'll keep looking.

[tibby01]

yeah, i know it will be the final gear's ratio that determines it. but im just assuming that for smooth acceleration purposes, the auto's fourth gear will have a higher gear ratio than the manual's fifth gear, which would allow the manual tranny to be capable of higher speeds. i dont even know if any of this would matter though, since automatic trannies use sun gears and what not...

[tibby01]

i found the gear ratios... it actually turns out that the auto has a lower final gear ratio, so it should be able to top out at a higher speed.

manual
http://www.hmaservice.com/webtech/ii...783#_394880783

auto
http://www.hmaservice.com/webtech/ii...731#_394880731

btw guys...use that website for everything...it is an online manual; my BIBLE!!!!

[ColeIketani]

ok that helps for the 2001, so what about the 2003?

[tibby01]

whoops, slightly different...

MT
http://www.hmaservice.com/webtech/ii...292#_394886292

AT
http://www.hmaservice.com/webtech/ii...298#_394886298

[Adam_Hunsicker]

Thanks for finding the info tibby.... I forgot all about webtech.... anyways, with this in mind, and considering the difference in weight I'd say the auto and the manual probably have about the same top speed... the manual would get to that speed faster, but the auto may be able to go a little faster in the end.....

[Bad_Tuscani]

I'm not a mechanic, but that would be my guess too...

[ColeIketani]

and what did we establish that speed being?

[tibby01]

LOL...undecided

no clue dude, the best way to find out is to get a cop out to the salt flats, and have him radar you.

[ColeIketani]

LOL fabulous

[Adam_Hunsicker]

Ok guys, here's the verdict.... I put my stock airbox back on, got ahold of one of my friends with Military Police and had him radar me on amboy road.... long, flat and at about 3500ft above sea level.... he got me at 143mph, my speedo said I was doing 141... just a hair over 140... I then put my homemade SRI back on and had him clock me again... 150mph, speedo said I was the width of the needle above 150. So, the speedo is slightly innacurate but top speed at my elevation in a COMPLETELY stock I4 automatic is about 143 mph.

[ColeIketani]

alright!!
so lets give us 1 or two mph leniancy for elevation. tight!

[Midnight_Outlaw]

Hmmm....and hello! acording to math at the 6250rpm red line the top speed with out any drag on a 5 speed (2001) i4 is 137.8mph
You can see the chart here,
Press me!

for the (2003) 4 speed auto i4 at the 6250rpm red line, its 140.8mph with no aero drag on the car See the link for more info (sorry for the 5th gear row but you have to at least enter 5 #'s!! gay..)
Press me!!

Now what is REALLY!!! shocking is for the (2001) i4 4 speed auto the top speed is a ungodly 176.2mph!!!!!!!!! at the 6250rpm red line but thats with no aero drag, so if you were on the moon then you could go about that fast in a stock auto tib!

Press me! please im lonly

The 2003 5-speed top speed at 6250rpm is only 130.1mph


Click here


That is with 0 aero drag on the car so the auctual top speed will be lower.

If you really did do 150mph in 2003 your auto tib you must have been way over the red line like at almost 7000rpm

[Dunn]

While the numbers might be true in theory they are wrong in practice. I frequently have my Tib up to about 120-135 on the interstate here on the way home from work, and it's only 4th gear at about 3500 RPMs (this is in an '03 GT V6 auto). I've also brought it up to over 150 (about 152) a couple of times when the weather was PERFECT (i.e. cold dense air) and my engine was just at the right temp (pulled it off exactly 3 time). Sometimes I can still get close to there but usually bottom out right around 145 and it simply WON'T accelerate more even though I'm only at about 5k RPMs). So while the numbers may work out good they are not necessarily true in practice.