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Automatic Transmission Performance

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Old 02-23-2011 | 02:48 AM
  #16  
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You need to learn how to drive the automatic properly. It's not obvious. If you leave it in D, you'll be bored to tears, but once you learn to row the shifter correctly, the autobox car really comes alive. Still it's nice to have D as a hands-free option when I am munching on a Quarter Pounder.
Old 02-23-2011 | 03:08 AM
  #17  
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Another automatic fan here. Had a 91 GT in-between two S4 Automatics - the GT only lasted 8 months with me. Then I was tired of the long shifter throw, the awkward seating position (I had to move far forward in order to be able to depress the clutch all the way), and dealing with the clutch in heavy Bay Area traffic. Granted, that GT was a rocket, but the S4 is plenty fast.

I shift mine manually whenever I feel like. I've even practiced 3rd-to-2nd downshifts during deceleration (engine braking) with a blip of throttle to smoothen things out. It's a lot of fun, and you have the best of both worlds.

Originally Posted by ROG100
The 928 was designed for an automatic gearbox and the manual was a second thought. Hence the very low numbers of 5 speeds made. If they were that good why did most cars come with an auto.
I agree with most of what Roger wrote, except this. In fact, it is specifically not true.

When they designed the 928, it was designed and prototyped with a 5-Speed manual transmission. By the time they test fitted the automatic for the first time, the sheet metal for the floor pan was already going into production. Then they realized there wasn't enough space for the torque converter between those rear seats. The only solution was to make a second version of the sheet metal surrounding the transmission as well as narrower rear seats.

I am pretty sure this is one reason why the automatic came months later than the manual transmission models.

They made these separate bodies until about 1983; then the automatic style body became standard for all 928s. This means, you can convert any of the later 5-Speed manual 928s to an automatic, if you get tired of shifting.

Isn't that great?

Old 02-23-2011 | 03:32 AM
  #18  
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Nicole, how many RPM are you turning in 4th gear at 60 on the highway? Check that for me and let me know please.

Also did you used to have sill plate "covers" in your store? I had seen those somewhere along the way and they would be perfect for EURO85 as they would cover the broken part of the existing plate...black or something NOT shiny would be my preference...
Old 02-23-2011 | 04:38 AM
  #19  
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Originally Posted by pcar928fan
Nicole, how many RPM are you turning in 4th gear at 60 on the highway? Check that for me and let me know please.
I won't be driving for a while... eye surgery on Thursday. Remind me in about 2-3 weeks.

Originally Posted by pcar928fan
Also did you used to have sill plate "covers" in your store? I had seen those somewhere along the way and they would be perfect for EURO85 as they would cover the broken part of the existing plate...black or something NOT shiny would be my preference...
I still offer "928" lettering for the door sills, but I don't have the stainless inserts anymore. I've been thinking of having those remade, but the lack of interest last time didn't put this high on the priority list. The letters come in all kinds of colors and materials; all can be made matte with 2000 grit sand paper.
Old 02-23-2011 | 06:52 AM
  #20  
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Hey guys, thank you for all the replies, so I guess there are many automatic fans around here, that's great.

Not to really shift course, but while i have so many opinions here, I have been reading about the thrust bearing issue, and was wondering how you guys deal with it?

Do you guys have that process done every time it is in for service (the taking off of the bell housing etc.), or every other time, would love to hear your input.
Old 02-23-2011 | 07:00 AM
  #21  
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This issue becomes increasingly important with higher miles. I'd say, from 60k miles on, the frequency of the check should increase exponentially - particularly once you find pressure on the plate.

I have 105k miles on the odometer and drive about 5k miles per year. I try to have it checked once a year, but we don't always find any measurable pressure. To make it easier, and save ourselves from having to drop the exhaust every time, we left two bolts out of the lower bellhousing cover.

Other ways to deal with this issue is to have an enhanced clamp installed (e.g. the super clamp from Constantine), or to install an older style torque tube that prevents the shaft from moving forward, towards your engine.

However, the flex plate should be checked no matter what.
Old 02-23-2011 | 08:52 AM
  #22  
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(Obscure side reference to follow)

The 944 auto uses a front flexplate that consists of a huge rubber diaphram with a splined hole centered in it. They dry rot with age. Hugely expensive to replace.

Clutch conversion is possible because the firewall is pre-formed; clutch sets from wrecks are cheap.

Several enthusiasts have to set-up a 944 automatic driven through a clutch instead of this flexplate.

So, to Nicoles point, you could probably convert a manual 928 into an automatic ---- and retain the clutch.
(Makes more sense if you are struggling daily with 1-3 shifts and no 3-2 downshift because your early manual is worn out)
Old 02-23-2011 | 09:41 AM
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Hmm, my first two were auto boxes, fine trannies for sure, but my current, early 5 speed is great - I am loving it! I find I have much more control over speed and power delivery, and while it's not a "snick snick" type of shifting action, it is just fine for my purposes. I've also driven Kyle's old 85 short shift, and that was fantastic (mine doesn't have the short shifter installed, nor do I want one at this point). In short, the autos are great, and yes, adjustments can be made, but it is a very diferent driving experience from a 5 speed. Just my $.02.
Old 02-23-2011 | 10:06 AM
  #24  
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Originally Posted by phinfan
Hey guys, thank you for all the replies, so I guess there are many automatic fans around here, that's great.

Not to really shift course, but while i have so many opinions here, I have been reading about the thrust bearing issue, and was wondering how you guys deal with it?

Do you guys have that process done every time it is in for service (the taking off of the bell housing etc.), or every other time, would love to hear your input.
Search for the SuperClamp, or Constintine.
Old 02-23-2011 | 10:30 AM
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Originally Posted by blown 87
Search for the SuperClamp, or Constintine.
or Pklamp
Old 02-23-2011 | 10:58 AM
  #26  
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Doesn't the AT comes with a build in cooler connect to the radiator? One thing I don't like about the my AT is the leaks. I have been trying to fix it for years. It is sitting on my lift right now with new pan gasket and silicon sealant to dry before I tighten it. If this doesn't work, I will tear out my hair before I loose it all.
Old 02-23-2011 | 12:12 PM
  #27  
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Check out my recent thread Special 1989 S4 for sale.

This car has a very trick Steve Cattaneo spec. Auto Transmission. AMG hardened planetaries, custom valve body, kickdown bypass switch, synthetic fluid, extra trans. cooler. I love punching it at 60 mph and it shifts all the way down to second gear... 100 mph is soon to follow!
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Old 02-23-2011 | 12:30 PM
  #28  
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what Roger and other have said, the 2.54 4-speed auto with LSD, 1st gear starts and properly functioning kick-down is the closest thing to mind control of a car, can't be beat.
Old 02-23-2011 | 02:03 PM
  #29  
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Bill Ball states "...You need to learn how to drive the automatic properly. It's not obvious. If you leave it in D, you'll be bored to tears, but once you learn to row the shifter correctly, the autobox car really comes alive...." So Roger that would seem to indicate that you still need to let go of the steering wheel to row the gears and trick the automatic into shifting closer to when you would like it to shift. Then with a nice round leather shift **** and leather boot it might just look a bit like a stick shift lever when someone looks inside your sports car....odds are they will not notice the missing clutch pedal right away.
Old 02-23-2011 | 02:21 PM
  #30  
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Originally Posted by Nicole
I won't be driving for a while... eye surgery on Thursday. Remind me in about 2-3 weeks.

I still offer "928" lettering for the door sills, but I don't have the stainless inserts anymore. I've been thinking of having those remade, but the lack of interest last time didn't put this high on the priority list. The letters come in all kinds of colors and materials; all can be made matte with 2000 grit sand paper.

I have access to a fine water laser cutter which can make quantities of something _really_ cheap to do.

Just needs someone to do the Cad drawing..the expense if if the shop has to manage the artwork for you.


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