(edit)2400 rpm at 80mph

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09-24-2008, 11:44 PM

#16

Mrmerlin

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Brendan could you please post the year and model of your car also any options, I m trying to figure out whats going on

09-25-2008, 12:19 AM

#17

no doubt

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Quote:

Originally Posted by BrendanC

maybe you have the 89 2.64 rear?

... .

Maybe the Euro 2.54 final rear drive? That was optional for 86 and 89 automatics, yes?

09-25-2008, 12:44 AM

#18

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Quote:

Originally Posted by Mrmerlin

Brendan could you please post the year and model of your car also any options, I m trying to figure out whats going on

1982 Competition 5spd. Transmission was replaced a couple times over the years. Obviously because no one fixed the clutch. It was rebuilt by devek in 2006. I think there is a very good chance that a later trans was bought, rebuilt, and put in.

09-25-2008, 01:03 AM

#19

jorj7

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Brendan,

Even with my 2.2 rear end and 18" wheels with 26.6" diameter tires, I get 72 mph at 2000 rpm.
so it's definintely not a 2.75 or 2.54 rearend in that car.... By the way a 2.75 with these tires is
58 mph and a 2.54 would be 62 mph at 2K rpm.

09-25-2008, 01:20 AM

#20

mark kibort

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It might change on the radar gun, but on the speedo vs the RPM, that is fixed

mk

Quote:

Originally Posted by Jim bailey - 928 International

80 mph is about 2400 rpm on the 2.20 with stock tire diameter anything taller and it really changes

09-25-2008, 01:23 AM

#21

mark kibort

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84s have a 2.22 rear end. I had one , and it was exactly 70mph at 2,000rpm and near 80 at 2400rpm.

either way, you might have an error on the tach or on the speedo.

mk

Quote:

Originally Posted by BrendanC

Well, no 160, but verified that at 80, I have right at 2200rpm. So now its time to get under there and see what the 28/0x is. Methinks its like an 83 or 84 usa 2.2, but not the borg warner 2.2

09-25-2008, 03:58 PM

#22

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I checked again and its at 2400 at 80. Can't quite get under it at work to see the number. Trying to find a mirror.

09-25-2008, 04:26 PM

#23

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I got under the car with a mirror so I could see the numbers at the office. It says, I think, 28/08, which would make at, as was suggested, probably an 83 or 84 US. Making it a 2.36 rear end if everything matches up.

09-25-2008, 04:53 PM

#24

Jim bailey - 928 International

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would be a 2.26666666666666666 , ratio 15:34

Jim bailey - 928 International is offline

09-25-2008, 05:00 PM

#25

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2.26? Or 2.36?

Published says 2.36

09-25-2008, 05:42 PM

#26

dr bob

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Brendan, some friendly advice: DO NOT DISASSEMBLE ANYTHING TO "FIND OUT"!!! Driving is more fun than tinkering, so why risk a relapse?

09-25-2008, 05:49 PM

#27

Jim bailey - 928 International

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The 34 divided by the 15 is 2.2666666 , do always believe what you read

09-25-2008, 05:50 PM

#28

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Quote:

Originally Posted by dr bob

Brendan, some friendly advice: DO NOT DISASSEMBLE ANYTHING TO "FIND OUT"!!! Driving is more fun than tinkering, so why risk a relapse?

Ah, not disassembling to find out. Must take transmission out to fix 2nd gear issue ( https://rennlist.com/forums/928-forum/456244-won-t-go-into-2nd-but-all-other-gears-perfect.html )

To make sure the car runs and drives within the time alotted for me to get to work, I would put in the already rebuilt 78 TT and trans. And maybe the K-member if I need it.