Transmission swap

Maintenance advice to keep your Spider in shape.
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jlw35
Posts: 130
Joined: Mon May 20, 2013 7:18 am
Your car is a: 1975 spider

Transmission swap

Post by jlw35 »

My '75 Spider's tranny has some leaks, and some metal in the pan.
I happen to have a tranny from a '80 Spider 2000.
Both are manual.
Can I do a direct swap, or are modifications necessary?

Thanks
Jeff

Also, looking for a machine shop in the St. Louis, MO area to rework the head (someone familiar with the Spider), any leads?
So Cal Mark

Re: Transmission swap

Post by So Cal Mark »

swap away
jlw35
Posts: 130
Joined: Mon May 20, 2013 7:18 am
Your car is a: 1975 spider

Re: Transmission swap

Post by jlw35 »

Ha, thanks for the quick reply Mark, and the good news.

Jeff
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FiatMac
Posts: 290
Joined: Sat Aug 01, 2009 1:14 pm
Your car is a: 1982 2000 Spider
Location: Salisbury, North Carolina

Re: Transmission swap

Post by FiatMac »

Your only issue will be that the speedometer will register slower than you are really going by about 10% unless you disassemble the '80 transmission and install new speedometer drive gear. The '75 transmission speedometer drive gear was set up for a 4.3 rear end ratio and the '80 was set up for a 3.9 ratio.
Stan McConnell
Retired Mechanical Engineer
Salisbury, North Carolina
82 2000 Spider (driving)
78 124 Spider on the rotisserie
76 124 Spider parts car or possible Lemons racer
83 parts car
jlw35
Posts: 130
Joined: Mon May 20, 2013 7:18 am
Your car is a: 1975 spider

Re: Transmission swap

Post by jlw35 »

Good point Fiatmac.
Thanks
Jeff
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: Transmission swap

Post by bradartigue »

...and given that your speedometer came with an inaccuracy rating of about 10% to begin with, well, you'll be fine. Who really uses these things anyway?
vandor
Posts: 3996
Joined: Sat May 23, 2009 1:23 pm
Your car is a: 1971 124 Spider
Location: Texas, USA

Re: Transmission swap

Post by vandor »

Clarification: the speedometer drive gear in the transmission and the speedo drive that is bolted to the transmission is a matched pair. If one installs either one that has a different number of teeth from the original, they will grind themselves to pieces. They must be replaced as a matching pair (as far as number of teeth go - they do not have to come from the same car).
Csaba
'71 124 Spider, much modified
'17 124 Abarth, silver
http://italiancarclub.com/csaba/
Co-owner of the best dang Fiat parts place in town
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