SIMCA TRANSAXLE INTO 850 SPIDER?

[Frank L. Di Gioia]

According to ancient rumor the 4.38:1 Simca transaxle will bolt onto a 903 Fiat engine. At that time (60's) Simca was associated with Fiat and shared a lot of parts. Everything looks the same in pics but we've all been there before. I'd ppreciate any help, thanks in advance.

 

[dnudelman]

Don't know if this helps much. I raced a 600 based Alemano spider. The rear stub axles and flex couplings were Simca.

 

[Dr.Jeff]

Frank, would a Simca transaxle even be available? And if so, what are its advantages to the Fiat one (remember, I know nothing about 850's)?

 

[gene cooley]

According to ancient rumor the 4.38:1 Simca transaxle will bolt onto a 903 Fiat engine. At that time (60's) Simca was associated with Fiat and shared a lot of parts. Everything looks the same in pics but we've all been there before. I'd ppreciate any help, thanks in advance.

"Fiat and Abarth Tricks" might be the best place to start. The first question I would have is whether the Simca engine is CW or CCW.

 

[ramona300]

The ring and pinion do with slight modification.

http://www.abarthweb.com/abarthtricks.pdf

There is a Youtube video also that shows this.

 

[Frank L. Di Gioia]

Frank, would a Simca transaxle even be available? And if so, what are its advantages to the Fiat one (remember, I know nothing about 850's)?

Jeff, the final drive ratio of the 850 Spider is 4.88:1 vs 4.38:1 for the Simca. Not a great difference BUT with lower profile tires the 4.88 will really buzz the motor on the freeway. Given enough time an 850 can hit redline on the straight and level. If drafting another car it will easily exceed redline.
I found a Simca transaxle but was hopefulit would be a direct bolt-in. Dream on.....

 

[Frank L. Di Gioia]

The ring and pinion do with slight modification.

http://www.abarthweb.com/abarthtricks.pdf

There is a Youtube video also that shows this.

Thanks Ramona, The videos answered my question. No for the total swap without mods.

 

[Frank L. Di Gioia]

"Fiat and Abarth Tricks" might be the best place to start. The first question I would have is whether the Simca engine is CW or CCW.

Thanks Gene,
Never even thought of that! My dream of a direct bolt-in was just that, a dream.

 

[Frank L. Di Gioia]

Don't know if this helps much. I raced a 600 based Alemano spider. The rear stub axles and flex couplings were Simca.

Thanks, good to know. I was hopeful of a direct replacement but a lot of parts do look interchangeable.

 

[ramona300]

The cheapest and easiest way to get a more usable final drive is to source an early 850 sedan gearbox from the model that used 12-inch wheels. This will give you a final drive ratio of 4.63. This and bigger 13 inch tyres should do the trick. Speedo will be wrong but everything just bolts up!