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Torque Converter Swap to Increase Stall Speed?

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Old 01-28-2014, 10:52 AM
  #16  
killav
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Originally Posted by Avar928
Yea, I can always read that thread about Corvettes trans. I get what you're saying, I'm a stickler for trying to get it all so I'd probably need to compare all that stuff before deciding which route to go. I wouldn't mind sacrificing several miles off the top end to get much better acceleration on the lower end as well since our area doesn't really allow you to open them up.
This. My ***** run out of steam long before my 2.20 geared car does.......
Old 01-28-2014, 02:01 PM
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James Bailey
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a 2.75 final drive gets you 155 MPH @ 6,000 rpm which for most is fast enough
Old 01-28-2014, 03:15 PM
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PorKen
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Is the the Bowden cable taught? (Cable end should drop straight down on to the ball.)
Just having this adjusted correctly will make a world of difference.

Or, have you tried a turn or two tighter?
This will keep it in a gear longer and will kick down at part throttle sooner.
Both will make it more responsive (with zero cost).
Old 01-28-2014, 07:31 PM
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Avar928
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Bowden is taught. Drops on the ball. I just serviced the transmission and differential but haven't taken her out yet. She was really low on ATF.

155 seems fast enough doubt I'll ever need to reach those speeds unless I want to so a track day?
Old 01-30-2014, 10:39 PM
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SMTCapeCod
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Archive dive:
https://rennlist.com/forums/928-foru...speed-mod.html

PS Mike I called it on the bowden cable comment..

;-)
Old 01-30-2014, 10:42 PM
  #21  
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whups.
Old 01-31-2014, 06:48 PM
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928Shane
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I remember a 454 chevy with a 3800 stall behind it and 2.73 gears. The guy was driving it to and from tech school,converter balooned and ended up pushing the crank thru the thrust bearing and into the block. With all the concern about thrust bearing wear on these cars i'd be leary of putting in a looser converter. but thats just me.
Old 01-31-2014, 09:06 PM
  #23  
Avar928
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Trans just needs slightly more fluid after having driven her around a while and circulating. Bowden adjustment really made a big difference, everything you said basically. I noticed a knocking sound when she's in gear though, coming from around the trans.

My stall is currently at 1800. I do think 2200 would do wonders. Still looks like a hit and miss.
Old 01-31-2014, 10:45 PM
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andy-gts
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Greg put in a higher stall converter in my stroke but I think it was still a stock converter from an earlier model. He rebuild the trans with more clutch plates, 2.2 rear end and modified the shift at wot to shift at near red line for every shift…. I think he tried a couple different torque converters and finally hit on one he liked…I will pm him and see if he can remember…I don't have my parts sheet anywhere near me…or I would read it off….
Old 01-31-2014, 10:57 PM
  #25  
danglerb
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Zeus+ put a higher stall in his I think S4 and said he liked the results a lot.

I recall the Euro converter, at least in my 84 had something like a 2350 stall speed instead of US 1950.
Old 02-01-2014, 01:46 AM
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James Bailey
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Sounds about right since the 4.7 Euro S needed to get up on the cam to compensate for less low rpm torque. One Mercedes trans guy said some small diesel M B s also used higher stall speeds to get them rolling.
Old 02-01-2014, 12:08 PM
  #27  
Avar928
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http://members.rennlist.com/pirtle/s4atrans.htm

Gives the transmissions for all 1985-1989. The US really got the short end of the stick. I wonder why they did that.
Old 02-01-2014, 01:06 PM
  #28  
FredR
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I doubt any stock motor powered automatic with either the 2.54 [euro spec] and for sure 2.2 [US] will rev out in top gear unless you drive down a mountain. I seem to remember that my 2.54 in the late S4 pulls to about 5,500 [?] when it was tapped out- an indicated 270 kph but not been up there for a long long time. Always found it kind of ironic that the 5 speed manual has a 2.75 and a 4 speed auto 2.54 [even 2.2 on some US models]. Of course completely different when you have an Uber motor. Not sure what the score is in a GT when it is flat out. I think I would prefer a 2.75 on my S4 motor were it available for automatics.

Regards

Fred
Old 02-01-2014, 01:15 PM
  #29  
James Bailey
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Originally Posted by Avar928
http://members.rennlist.com/pirtle/s4atrans.htm

Gives the transmissions for all 1985-1989. The US really got the short end of the stick. I wonder why they did that.
For the MPG stickers on the window and "gas Guzzler" taxes plus Porsche has always considered USA speed limits and driving style to be vastly inferior Need only consider the 914 being badged a Porsche, the stupid 912E to use up excess 914 motors, the dumping of the left over 85 suspension and brakes on the first 1000 of the 1986 USA cars, the really low power of the 1980-1984 USA 928s, Calling the 83-84 USA cars an S is like a bull with no ***** being called a bull......Any way you get the point
Old 02-03-2014, 01:41 PM
  #30  
Avar928
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Originally Posted by FredR
I doubt any stock motor powered automatic with either the 2.54 [euro spec] and for sure 2.2 [US] will rev out in top gear unless you drive down a mountain. I seem to remember that my 2.54 in the late S4 pulls to about 5,500 [?] when it was tapped out- an indicated 270 kph but not been up there for a long long time. Always found it kind of ironic that the 5 speed manual has a 2.75 and a 4 speed auto 2.54 [even 2.2 on some US models]. Of course completely different when you have an Uber motor. Not sure what the score is in a GT when it is flat out. I think I would prefer a 2.75 on my S4 motor were it available for automatics.

Regards

Fred
I guess I'm thinking relative to the increased red line on the S3000 chips but top gear max out isn't due to the stock computers cutting out at that point?


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