356 gearbox types

renzo · Post by **renzo** » Sun Nov 05, 2006 8:30 pm

Hello,

does anybody know about the gearbox types ?

The type of my 356 SC 1963 gearbox is : 741 / 2C (serialnumber = 71191)

741 is the type for SC models, but what does the "2C" means ?

thank's !

Lightweight_911 · Post by **Lightweight_911** » Sun Nov 05, 2006 9:42 pm

I think the 2C suffix was used to identify the gear ratios used in that version of the 741 transmission.

renzo · Post by **renzo** » Sun Nov 05, 2006 9:54 pm

ok thank's. I think so, too.

but which ratio could have the "2c" suffix ?

higs356 · Post by **higs356** » Mon Nov 06, 2006 3:23 pm

the 741-XC was made between Aug 63 to March 65 . Before that they were 741-A but looked exactly the sameon the outside.

Going by your serial number its one of the early ones... in the first 200 xC boxes made which would suggest it is probably the correct box for your car if it is a 63

All of the XC boxes have the highly desirable 12 bolt diff carrier making them really tough
the 2C has BBBD gears (long 4th )
the 0C has BBBC gears (shorter 4th)

For Ref the speedster typically had BBAB with shorter 3rd and 4th ratios

I should add the 356SC with the SC engine and this Trans with Disk brakes is one of the nicest driving 356s but then you already knew that

renzo · Post by **renzo** » Mon Nov 06, 2006 10:26 pm

thank you very much for this additional and interesting information !

I presume that every gear letter correspond to a definite gear ratio ? where could i find thes specifications ?

Mike Smith · Post by **Mike Smith** » Tue Nov 07, 2006 7:19 pm

1B 11 : 34
1C 12 : 33

2C 15 : 32
2A 16 : 31
2B 17 : 30
2D & 3F 18 : 29

3E 20 : 27
3A 22 : 27
3B 23 ; 26
3C 24 : 25

4A 25 : 24
4B 26 : 23
4D 27 : 23
4C 27 : 22
4TG 28 : 21

I hope I have listed these correctly ?

These are the number of teeth per gear
The 1st number is the teeth on the input shaft

I run the TG in my `C` Coupe - Great gear - It allows high speed cruising without approaching the Red Zone

Jim Clark Car runs C B A A

Mike at PR

renzo · Post by **renzo** » Tue Nov 07, 2006 8:56 pm

ok perfekt ! Thank you very much. It's exactly what I wanted to know !

Ratio
1B 11:34 = 3.091
1C 12:33 = 2.750

2C 15:32 = 2.133
2A 16:31 = 1.938
2B 17:30 = 1.765
2D&3F 18:29 = 1.611

3E 20:27 = 1.350
3A 22:27 = 1.227
3B 23:26 = 1.130
3C 24:25 = 1.042

4A 25:24 = 0.960
4B 26:23 = 0.885
4D 27:23 = 0.852
4C 27:22 = 0.815
4TG 28:21 = 0.750