IcemanG17

Back on crankshafts

This has me thinking....I know automatics have an upper RPM limit where the torque converter stops working.....I've heard anything from 6500 to 7000rpm.... SO how fast can a 928 automatic turn and not break the torque converter....a great question for this thread, since we now have the ability to reliaby turn higher RPM...... No sense building an engine that can turn 8k, if the trans can only take 6.5

BC

This comment is in line with the original idea of the thread, so I consider it on topic:

Rational thought tells us that we need to figure out what our goals are. What is our purpose, or business case, if you will, for doing something. What do we want the end result to be?

In Racing, the only goal is to win. There is no other goal. The top racing drivers (in the REAL sports, like F1, Le Mans, and our own DP races, only wish to win. They are not happy with third, or even second.

Only winning.

So - what do we need to do to win? It may be to build a better motor. Or cams, or suspension. It may be to even use a different driving technique. The car is simply a tool. The mechanics are other tools. For a team, a driver is just a tool as well. A tool to be used for the purpose of winning.

The driver's responsibility, as Greg pointed out, is simply to drive, and the mechanics and engineers to build a car that suits their style, as long as that style ends up winning.

If a race is 75 laps, and the driver drives to make it last 76, he is not using his tools properly. If he drives and wins in 75 laps and the car is used up, it does not (or should not) matter. No one wins awards for driving nicely. They win awards for... winning.


Greg is making pieces that are tools for someone that wishes to have the engines last - and in the extremity of the point - to win. That is all. And it is rational and logical to do so. Any superfluous argument about how one or another can make lesser pieces "last" longer does not matter. The point is being missed. All that resides down that path is ego - and ego has no real purpose or place in the true path to winning. It usually simply lays in the middle of the road, distracting and stupidly questioning others - as it has here.

No one is racing automatics, really, except you and a few open-roaders.

IcemanG17

true....but it is the stronger trans...by a wide margin..... plus automatic just sounds so slow....I prefer "poor mans sequential"..... which it really is

BC

It just too sloppy for me. I can't stand it on the street, let alone somewhere I actually need to go fast.

GregBBRD

I have no idea about this. I do know that Andy's automatic seems to work fine past 7000.

I have a "street" Nova that has a Powerglide in it that I spin to 7,000. I only stop there because it's a 540 cubic inch Big Block and it just doesn't seem like I need to spin it any harder.

People with "Small Blocks" routinely spin automatics well into the 8,000 rpm range.

Guess we will find out about the Mercedes automatics.

John Speake

I don't think there is a particular rpm issue, unless you're assuming more rpm = more power. Then the usual power related failure modes come in, like overheating, blade failure, ballooning etc.

I would think Andy's 928 is probably the highest power ever put through the 928 auto 'box.

Ah ! I forgot Brett's 2000HP 200MPH Euro S2 which is an auto :-)

hacker-pschorr

It's in the top 3
The other two run on DOT drag radials in the rear.

The only modification Todd has made to his auto's is adjusting them to shift harder.
And fluids from here:
http://www.lelubricants.com/transmission-fluids.html

The turbo doesn't have a gear vendor OD like the supercharged car.

He is looking into upgrading the torque tube.

dcrasta

Great series of books .. Smooth is fast..

blown 87

Greg, what do you see the absolute top RPM of the next version of your 928 motors to be?

mark kibort

you must not race. Unfortunately, the sport doesnt pay most drivers to drive their cars to win, most put characters in their cars and they perform as they have during their career. some too agressive, some fast, some consistant, some smart some stupid, its like no other sport. however, the main objective is not to just win, its to survive. survive and win might not be synonomous, but survive, smart and win usually are, just as survive, "not quite the fastest", bu the smartest can win championships. several WCGT race series were won buy guys that never won the race. the goal was the championship. so, winning is releative. plus, most guys out there are so happy to be out there, to finish on the podium, all the time, is more than enough for them. everyone wants to win, but many teams are very happy with strong finishes, expeically if the sponsors are happy.

Now, there is nothing wrong with making stuff better. Im not arguing that point in my rants before, i was only stating that if the 928 is taken care of, it can be rung out at the track, using all that it has and by the way, that can be done in a way that leaves some car left over for the next weekend. coicidnetaly enough, most the time the fastest drivers are the ones that are the easiest on the equipment. (not always, sometimes). Ior should i say, they can be easier on the equipment than a driver that is wasting time being rough on it.

IcemanG17

BRANDON

Okay seriously............here is my offer to YOU..... COME DRIVE MY AUTOMATIC RACE 928.... YES automatics have all this "drama" around them....but the reality is they WORK...

FLY up to Sacramento.....sign up for a track day, say the NCRC track weekend April 7-8, with a few other race 928's and you can DRIVE my 928 on track....I am 100% sure you will be impressed and walk away with a Everyone who ever has driven my car loves it....nearly every race 928 owner on the west coast can't be wrong.... I stand by my prior comment of any driver-any track...keep it under 6000 and it will live...

My only caveat is you must have prior DE-track day experience, since my car has no passenger seat or otherwise known as no instructor....

Don't knock the slushbox until you try it....

BC

You have no idea what you just signed up for.

Seriously - I had purchased an auto for racing another 928 I had on the side - like a cheap one that would be a throw away. I had all the parts to do so. But I had not driven an auto for a while. During that time, I bought/sold an automatic S4, and boy - it reminded me how much I hate autos. Truly hate them - on the street. Obviously I have no driven them on track since I have only had 5spds to go to willow springs (big and Streets) as well as fontana and (cough) parking lot auto-x.

Professionally? No Mark, and neither do you.

GregBBRD

I'll be trying to move the power range up 800 to 1000 rpms. Not a big change, but it does require changing things around, a bit.

I'm guessing an "active" shift point at 7,600-7,800 and a limiter at 8,000-8,200.

Ninespub

Quote:
Originally Posted by mark kibort
you must not race.
Quote:
Orginally Posted by BC
Professionally? No Mark, and neither do you.

Whooooooooo........Slice AND Dice!

blown 87

Cool, looking forward to seeing the end results.