Ive been looking for some information regarding my topic but have come up short. Basically I would like to know is, can a 4 spd auto (a28) be modified to equal or exceed the performance of a 5 spd?.

I know about bypassing the KD switch, (mine is) but I want more. Call me greedy.

 

No.

Automatic transmissions require energy to run, so you are always going to have a performance deficit compared to a 5 speed. gm managed to build an auto corvette that was faster than the manual version primarily because the auto could shift quicker, but it was a marginal improvement.

The advantages of automatics are elsewhere.

-A great way to improve your auto's performance would be through lower gears. If you can fit a lower ratio final drive, I bet you will score huge gains in acceleration. 928's seem to me to be geared for high speeds, not for typical American driving.

N!

 

the auto definitely takes a lot of the pain out of driving! for everyday use, in traffic or even on the highway its a lot simpler and helps me to focus on other aspects of the experience. the 4spd has a great spread of power making it not so critical as to which gear your in and holding 1st and 2nd around town is fun for sure. id have a 5spd as a weekend car!

 

About the only thing you can do to raise the performance bar with the 4 speed tranny is to swap out the one you have (this only applies if you currently have the final drive ratio of 2.20:1) with a tranny model number A28.16 (came out starting in the 89 model year), which has a final drive ratio of 2.538:1.

hth-

 

Do you guys remember the 68-72 Oldsmobile 442 - W30 package?. First of all, One BAD *** muscle car - but what I remeber the most was the his & hers shifter by Hurst?.

BAsically the shift gate had two seperate "shift" patterns (I think) - One which was nromal for an auto (hers) and the other side was set up so you can bang the gears individually like a stick (his)

Is there anything out there that is similiar for a 928?. Jager doesn't have anything that I am aware of?.

TIA

<a href="http://www.cars-on-line.com/70olds8214.html" target="_blank">http://www.cars-on-line.com/70olds8214.html</a>

Here is a picture of a W30 - Hurst Dual gate Shifter

 

I'm a big fan of the 4 speed A/T. I truly think that any gains the 5 speed has on paper will evaporate in everday use among average drivers. The 5 speed has a quicker 1/4 e.t. on paper, but the A/T's are so much easier to launch and shift, and to do so consistently, that the A/T will typically beat the 5 speed counterpart at the strip. I've seen this time and time again at our local Shark Drags. On the track in a D.E., I've never seen anything that would lead me to believe that the 5 speed car has an advantage over my A/T. In actuality, I think I'm able to brake more aggressively since I'm not dealing with heal/toe issues.

If you are an Andretti or a Garlits, I'm not talking about you. If you're a typical driver, I think the A/T will yield better performance more consistently.

The main thing is to get in there and start working that gear selector. When you start to shift the A/T manually, you will liven up the car considerably. On the track, learn to left foot brake. These two techniques will make wanting a 5 speed more of a preference than a performance issue.

-Adam Birnbaum
'88 S4 A/T

 

I had a 70 gs 455 A/T,
(kickasscar) WAS OFF the line quicker
then a 4 speed.

 

Greg,

Are you talking about a Buick Grand Sport?

 

It's VERY hard to remove the soggy/sloppy feeling that the autos have. They can be made to go as fast, BUT they don't feel all that good.
The automatics feel very "chevy like"(sorry, but true).

 

Error - my bad

 

I don't know Weissach if that is all true. My shark will snap your head all the way up and on manual DownSift, put you in your seat pretty good.

 

I'm with Weissach on the "soggy" feeling that autos get.

It's NOT the solid sucking-your-butt-into-the-seat feeling that I'm talking about. Autos do that quite well.

I like my 5 speeds "instant reaction" feeling. There isn't a smooth shift when I suddenly lift off. Because there's minimal play in the drive train, theres a sudden snap that accompanys the lift off. Theres the same snap when you stomp on the gas. That snap is followed up by the feeling of strong acceleration.

It's the instant snap that keeps the 5 speed from feeling "soggy". The torque converter is normaly responsible for the "soggy" feeling.

However, I'm also in agreement with atb, the auto is fast under most conditions, because the transmittion shifts nearly perfectly into every gear, and it does with with perfect precision. With the mannual, you have the theoritical advantage of haveing more gears, allowing better gearing ratios, and if your perfect quicker, more aptly time shifts. The average driver can't hold par with the precision of the auto in shifting, both in the duration of shifting, and the timeing. Plus what happens when the human makes a mistake? That auto box will never make a mistake!

 

well, my auto dosent have a sloppy or soggy feel to it.. its rock hard!!

...wait a minute which forum is this?

 

Plenty of snap in my auto too, without the delay of pushing the clutch in and releasing it. But then I haven't got a chance to drive the 5sp. yet. Maybe I'll change my tune in a couple of weeks.

 

Performance issues aside, there's no denying that a manual transmission sounds better than an auto, and I have the 'proof' from our very community.

Before responding, please right-click and 'save target as' to your desktop and set it play over and over before responding:

<a href="http://www.fenetra.com/p928/lagunalap.mpg" target="_blank">http://www.fenetra.com/p928/lagunalap.mpg</a>

The clip was posted by 'Dennis K' and is a 928.

Just listen to that engine breathe between shifts and the throttle blips on down shifts...

Can anyone out there argue that an automatic can sound half as good?

The sound of a manual is the primary reason I love them so very much; performance reasons are a distant second.

Man, that is pure music!