Transmission discovery & info
05-14-2009, 01:52 PM
#1
Racer
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Transmission discovery & info
Well, today was the first time i've driven my 928 a reasonable distance in a couple of years. While it was in pieces I remembered that my transmission kicked me in the back on each year change, so I changed the vac pipe for new.
Today, with a nicely shifting transmission, I counted 4 gear changes, even with just very gentle acceleration. Maybe one of the PO's had the valve body modified? I'm happy about this, because I was planning on getting one of those first gear start modules.
Secondly, I wonder what my rear end ratio is? In top gear my engine is at about 2100rpm at 50mph. Can anybody tell me from this info? The diff cover has been drilled where the numbers should be, so I can't tell from that.
Now I want to get a g-tech, so I can see what my vitals are!
Today, with a nicely shifting transmission, I counted 4 gear changes, even with just very gentle acceleration. Maybe one of the PO's had the valve body modified? I'm happy about this, because I was planning on getting one of those first gear start modules.
Secondly, I wonder what my rear end ratio is? In top gear my engine is at about 2100rpm at 50mph. Can anybody tell me from this info? The diff cover has been drilled where the numbers should be, so I can't tell from that.
Now I want to get a g-tech, so I can see what my vitals are!
05-14-2009, 03:16 PM
#2
Racer
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Yes, its a euro, so that sounds likely...
According to 928.org.uk an S2 euro should be pulling 4900rpm @ 154mph, so my differential must have been changed for a none original one.
If my tach is correct, by my calculations i'll be pulling over 6k rpm @ the same speed in my car
Edit:
It looks like my final drive is 2.75 or 2.73, but from what I can find out, the 2.75 ratio was only available for 3 speed cars, and mine is 4 speed, and 2.73 was only available on 5 speeds. Are these combinations possible in a 4 speed car like mine?
According to 928.org.uk an S2 euro should be pulling 4900rpm @ 154mph, so my differential must have been changed for a none original one.
If my tach is correct, by my calculations i'll be pulling over 6k rpm @ the same speed in my car
Edit:
It looks like my final drive is 2.75 or 2.73, but from what I can find out, the 2.75 ratio was only available for 3 speed cars, and mine is 4 speed, and 2.73 was only available on 5 speeds. Are these combinations possible in a 4 speed car like mine?
05-15-2009, 05:06 AM
#6
Racer
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Lol... Ok, I counted 4 forward gears in total. I really didn't know that they already had first gear available under relaxed driving - I normally drive a Mercedes 500 SEL, and am quite familiar with the lazy starts.
I guess the final drive is 2.54 then, although it definately seems more like the 2.7* is installed, with me getting around 25mph per 1000 in top gear.
I wondered if it was even possible to take the differential from a manual or 3sp auto and install it into my car, because thats what it feels like.
I guess the final drive is 2.54 then, although it definately seems more like the 2.7* is installed, with me getting around 25mph per 1000 in top gear.
I wondered if it was even possible to take the differential from a manual or 3sp auto and install it into my car, because thats what it feels like.
