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Discussion Starter #1
Are they all the same?
Ratios/Strength etc.

What I am getting at is can you use any box with any engine?
Ta.
:D
 

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As far as I know all gearboxes have the same ratios in the 105/115 series except for the 1300 and the last two series of the spider (aerodinamica and series 4).

ratios 1600 / 1750 / 2000:
1 - 1:3.304
2 - 1:1.988
3 - 1:1.355
4 - 1:1
5 - 1:0.791
R - 1:3.010

I don't know about the strength, but I suspect they are all the same. They share the weak second gear for sure :D
 

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Hans. Have you done a spread sheet for the Revs/Speed, for the 105's like the 147/156 one.?
I would love to be able to check the speedo, but not sure what the actual revs to speed ratio is.
 

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IanM said:
Hans. Have you done a spread sheet for the Revs/Speed, for the 105's like the 147/156 one.?
I would love to be able to check the speedo, but not sure what the actual revs to speed ratio is.
Haven't done it. But I will make one tonight for you.
 

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I can't make the excelsheet because the final ratios are a problem. Depending what book or article I read, the final ratio of the 1750 GT Veloce is sometimes 4.555 : 1 and sometimes 4.1 : 1 :mad:

I can't find a reason for the differences like model years or so :(

Does anybody know?? :confused:
 

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selespeed said:
I can't make the excelsheet because the final ratios are a problem. Depending what book or article I read, the final ratio of the 1750 GT Veloce is sometimes 4.555 : 1 and sometimes 4.1 : 1 :mad:

I can't find a reason for the differences like model years or so :(

Does anybody know?? :confused:
Hans, I will check my owners book tonite, but could it be an option on the sheet, or does that make it to complex?
 

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Final drive ratio's are as follows.
Sprint GT 63-66 1570cc
4.555 to 1

1300 GTJ 68-74
4.555 to 1

1750 GTV 67-72.
4.1 to 1

2000GTV 71-76
4.1 to 1.

1600 GTA 65-69
4.555 to 1

Spider 1600 66-67
4.555 to 1.

spider 2000 71-82
4.1 to 1

The Gear ratiois tend to be the same, except the the 1300's seem to have 0.860:1, for the 5th, as appose to 0.791:1, on the 1600 to 2000 Engines.
This data is quickly taken from Richard Bremners Book.

The handbook for my 1750 quotes actual drive ratios as below.
1st 13.54:1
2nd 8.15:1
3rd 5.55:1
4th 4.1:1
5th 3.24:1

This is with final drive of 4.1:1.

Tyre size BTW is 165x14, not sure of the profile tho.

To answer Ricks question, they probably are the same box, but the 5th Gear will be different on a 1.3 Junior.
Some GTA's are probably different as well, for Racing reasons.
 

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Too bad I can't find the height of the tires anywhere. But if I am not mistaken (I calculated the result) the height is 80%

You can download the file over here
 
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