6.0-928S

Hey Mark, I know it's like adding a lower first gear & all that stuff. The point is THAT'S WHAT WE WANT! We aren't talking about a road race. We want fun, aggressive, street driving. That means there are stop signs, red lights, all kinds of stop & go driving. Lots of standing starts. Understand? Punching the throttle & chirping tires once in a while if yer in the mood.
Hammer

mark kibort

the point here is with a 2.2 does your power peak get you to 6400rpm at 118mph in WHATEVER gear you have ??? the answer is YES. with a 3.09, that same 4rd gear (in the 4.5:1 total ratio) is the same as the 3th gear with the 2.2. THIS IS THE POINT!!!!! both cars would be in some gear, doesnt matter what you call it, at the 1/4 mile finish with the same ratio tac'ing out at 6400rpm and 118mph. thats because its the same ratio. however, the 3.09 would or could have used a beter launch with the super low 1st gear. all other gears to 118mph would be the same same same!!!

Mk

6.0-928S

I'M NOT GOING OVER 118MPH ON THE STREET!!!!
Don't you get it? I WANT the launch!! I can't use the top gear on the street! Do you go that fast on the street?
Hammer

mark kibort

so, it now sounds like you may get it now. so you know you only get a new 1st gear and all other gears are the same. so, on the street, you can do those easy burners, but you can do this pretty easily with a stock 1st gear on the "street" and on street tires. anything over 25mph will be exactly the same, and this is the point. Like i said yesterday, i was rolling past some friends at the market, and at 25mph, i just punched it and laid some big 13" wide, 20ft long, black marks down the street with very little effort. (and thats with race rubber !) cant imagine doing that same trick with 50% more power and 50% of the speed. its not like you can floor it at 5mph anyway in 1st gear as the S4 is.

Mk

mark kibort

ok , say 75 or 55mph. because those would be the shift points with either the 3.09 or 2.2. the ONLY thing you get is an extra shift at 25mph. if you need that , great. bolt on a 3.09. but if you understand that all the gears after 25mph would be the same , then its kind of pointless, also reverting back to my point about grip. can you really get a launch with 3.09s above a 2.2 in 1st gear with street tires??? thats a bet i would be willing to make!

also, i was not talking about top gear, i was talking about 118mph in 3rd for a stock S4 or 118mph with a stock S4 with 3.09 in 4th. top gear for a 3.09 would be the same as a 2.2 in 4th. (ie 155mph or so.)

but, i though if you drive on the street, this means highway too, you would want a 5th gear that puts you at 2200rpms at 70mph. hmmmm that would require a 2.2 rear end. now you would have to run at 3000+rpm on the hyway at 70mph

MK

6.0-928S

I don't "just" get it! This is what the rest of us have meant all along. We are shifting the usable power bands, in their respective gears, to a more useful range for spirited street driving not road racing.
Hammer

6.0-928S

Most high performance mods are a trade-off. Very few help at both ends, economy & performance. Look at my avatar. Do you think I give a **** about the economy end?
Hammer

mark kibort

If it is what you have "ment" all along , then why do you continue to reference "shifting usable power bands"? you are not shifting anything , when the resultant gears are identical, except 1st. this is a trade off for loosing 5th, but after 1st there is no differernce. is that what you mean or understand?

Im just trying to ask if you know everything after 1st gear will be identical to a 2.2 for how you are going to use it. Plus, this coupled with your comment of the power band needed to be in the 3500rpm, makes me think you dont understand.

Mk

mark kibort

thats not exactly true either. not, a set of trade offs would be present if you compare a 2.75 box with a 2.2 box. not that has trade offs as the gear spacings are in the 5-15% range. when you get to the 30% range, you equal the gear spacing and this doenst change much other than 1st gear.

When talking about gear optimization , its really about the gear spacing, and unfortunately, we cant do anything here, as all the boxes have close to the same spacing between gears.

as far as having it all, my S4 still gets 22mph on the highway, and puts out 320hp at the rears! didnt loose much with the little mods ive done before. However, i would say that gutting the car was a HUGE trade off for lightness! (ie 700lbs!)

Mk

heinrich

Mark if we ignore the 1/2-gear .....

1st on 2.2 == 2nd on 3.09 (more or less). So....
When I engage that gear on either car, the 2.2 is doing zero miles per hour, but the 3.09 is already doing 45mph. At this point, the same gear (2 or 1) is driving these two cars, but the 3.09 is not having to lug from zero, all that mass, and the 2.2 is .... And no i really am not going to keep responding

mark kibort

this is a peculiar message. Im not exactly sure what your message or point here is, but let me try and understand.

you are saying that ..............ahhh heck, please explain! I think on this one below you are kind of way off base, if you think there is any type of difference after what you should say is 25mph (based on a 50mph redline in a stock 8.9:1 1st gear) 25mph would be the new redline of the 3.09 1st gear. after 25mph, both cars would be going the same speed and would then be in the same ratio gear (ie 3.09 would be in a 8.3:1 2nd gear, while the stock S4 2.2 would be in the 8.9 1st gear) since both cars are the same mass, and the speed at the first 3.09 gear change puts both cars at a 8.xx:1 total ratio from 25mph onward. and everygear up to 118mph would be the same too.

dont know if that answers the thought below, but i think your statement below is a little confusing, as i had to read it several times to see if i could make sense of it. in a race, the 3.09 would have a jump. we all agree this. at 25mph, providing it had the grip to take advantage of the lower new 1st gear , at 25mph it would be in the lead by some margin. however, when the 2.2 in 1st gear got to tha that same speed (although slightly behind) it would then be in the same ratio and have the same pulling power from that point all the way to the finish . around town, even better example, after 25mph, both cars would have the same gearing the only differnce would be the 3.09 1st gear. you have already said this in a prior post, so i know you know this.

another way of looking at this, would be if you ignor the 1/2 gear of the 3.09 1st. and just drove around in 2nd though 4th this would be the same as the stock 2.2 driving around in 1st through 3rd. they would have the same spacing and same number of shifts to a top redline speed of 118mph in 3rd for the S4 2.2 and 4th for the S4 3.09.



MK

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Randy V

The whole thing seems pretty straight-forward to me without the Kibort weird science.

A higher-ratio rear end = improved off-the-line performance. Period.

Shane

I'm with Randy on this one!!

I have a 3.09 and know for a FACT that it makes a difference! Not only that but if I had the $$'s I would be adding one to an auto tranny because I know for a FACT that it would make a difference.

mark kibort

is the wierd science the qualifiers??

to make truth out of that statement, you have to mean when comparing an S4 with 2.2 to a 3.09 diff change, and you can take advantage of the gearing change with grip, and its only to 25mph.

any other rear end change lower, would give better off line, but could improve accelerations to different target speeds. but, in this case, you are simply, right!

Mk

6.0-928S

So anyway, does anybody have an S4 auto ring & pinion to donate or sell me so I can get the patterns examined (at my expense) to get an estimate for an initial batch? Obviously if someone had a junk trans it would help.
Thanks, Hammer