Mark

There are FEW cars that can keep up with an A/T shark when you're cruising at about 50 and NAIL IT!

Even MORE fun if u do it with the Ott pipe, no cats and riding along next to a construction barrier - or in a tunnel!!

Thom1

Jayc67,

Too much bwaah if engaged all the time. I just use it when I want to get a grip and go. See the linked discussions. You can use it to stay in first longer at the light. I could not get mine to kickdown to second consistently when I wanted to pass on a 2 lane road - use it then too.

mpesik

Jayc67 . I have my kick down switch connections wired together. It's on all the time! If you modulate the pedal carefully the transmission will shift normally-Almost. My car is quite loud. I have a small gap between the manifold and cat. on one side .So-when you are somewhat agressive with the pedal other drivers can easily hear the engine revving up . Sounds like your maxing out the engine and not really going anywhere. Recently, I pulled the wire from the kickdown switch mod. ,took it for a spin . Pulled into the garage and put that wire back on ! I will always stay connected. Mike. B.T.W would this gap in my exhaust so close to the o2 sensor affect anything? Mike.

Jim bailey - 928 International

It energizes a relay on the fuse panel which in turn energizes the magnetic switch which acts on the "regulator" centrifugal governor thus allowing the downshift at higher than normal speeds . So if it is not working it can be the switch under the pedal , the relay , the switch on the trans , connections ............

Kaz

I leave mine in third around town otherwise as everyone else has said, too much BWAAAAH.

jayc67

I'll play with the switch mod and see what happens. So again, if this thing is "on" all the time, what are we wearing out quicker than usual....
Gotta be a price for using this all the time huh?

Thanks as always for the info.

Ispeed

I'm still getting the hang of everything, but the biggest thing I learned is to leave it in 3rd in twisty stuff. It engine brakes into corners and down hills like a manual. With a working kickdown switch (and aux switch) this is great stuff. I know the hardcore guys don't take the a/t seriously, but it really doesn't suck for street driving and agressive street driving. I didn't get a 928 to go to the track, but I may try it someday.

TroppoShark

G'day RazorRacer,

Thanks for posting this topic. I've wondered the same thing about selecting 2 and driving.

I've only had my shark for a little less than four months, and selected 2 for the first time last week (can you believe that?) and seriously scared myelf, because I couldn't easily get it back out and select 3...

Turns out that problem is related to the button-release on the shifter. Either it is so stiff from so little use of 2, or possibly needs an adjustment to clear more easily. But I do get the impression that it has rarely ever been shifted into 2, which the OM suggests is most appropriate for towing etc. Heaven forbid! Does anyone actually HAVE a towbar on their Shark...?

Basically, I just drive in 3 and D as appropriate for the conditions... and use kickdown when needed.

Kickdown is my current project, and I'm going through all the steps to ensure its smooth and reliable functioning.

Reliability of the kickdown, combined with being totally familiar with when it is on call, is essential, IMHO. I travel a lot on two-lane roads, and can't afford to commit to overtaking and then find that the operation is taking twice as long to execute as I presumed. Safety Safety Safety...

Cheers,

Phill.

Drewster67

Isn't that the truth! -

RazorRacer

I question if driving in 2nd really increases fuel consumption. The lugging of driving in "D" seems to waste more gas than driving in the sweet spot of 2nd. Of course at 40 mph in 2nd will waste more gas, but the starts and under 30 mph seem to perform better in 2nd. I really like flooring it in 2nd and slightly spinning the tires when it finally drops to 3rd.

ViribusUnits

The slower you turn the engine, the higher the specific out put you'll get.

This is because the largest lose in the engine, for a car with the engine the side of the 928's is the pumping loss. It takes energy to make vacuum. The faster you turn the engine, the more vaccum has to be made to keep the power down to maintain a steady cruise. As a result, the more fuel gets consumed.

This is the big reason why desiels are so much more efficent than gasoline engines, virtualy no pumping loses in comparason.

Jeff928S4

I have the digital dash that shows instant fuel consumption.

If you are in "D" and give it a certain amount of gas, you will be burning say "20" - if it's in "3", with the same situation, that "20" becomes "30". If you use "2", it goes up even more. "D" gives you the best fuel economy.

atb

My car stays in "2" most of the time. Good up to 94mph (drag strip verified by another S4 A/T), why mess with shifting?

Jim bailey - 928 International

Ah Adam , my first wife could never drive a manual transmission I remember her looking at me and saying "Why should I shift ?" as we rolled along in 1 st gear at way too high an RPM (not in a 928) . A good friend of mine had a daughter who is profoundly deaf but learned to drive a 5 speed manual very well , she could feel when it was time to shift . That impressed me .

dr bob

Anybody remember tge 'shift!' lights in some '80s stck cars? They seemed to want you to shift at absurdly low engine speeds, to the point where the engine seemed to be lugging if you increased load at all... And that's the secret. If you were just cruiisng steady speed steady engine load, shifiting with the light did/does in fact produce the best mileage.\\

Fast-Forward (and I mean that in the most literal sense...) to today, and now I have the '89 S4 with the digital display and the instant MPG display option. It clearly shows that using the higher gear gives better mileage, even under hill-climbing load.

As much fun as it is to drive with the car in a lower gear, for that quicker 'snap' response from the loud pedal, most engine wear items should probably be indexed to total revolutions times the square of the engine speed. This would apply directly to friction surfaces for sure... and what else is there that's sensitive under the hood anyway. Think about timing belt wear as a function of engine miles rather than car miles, and you'll get the idea. The belt doesn't know how many miles have rolled under the tires, only how many times it's looped around the pullies. So you guys who drive in lower gears all the time, redo your timing belt and water pump replacement intervals to reflect the extra engine revolutions.

Other 'wear' item like torque tube bearings fall into the same category, as do all the engine accessory drive items like the alternator and steering pump.


Are ya --sure-- ya want to drive around in the lower gears all the time?