All USA B310 were fitted with hydraulic clutch

B310 never came with 63a, they are instead from B210 with A14 1976.5 to 1978

Aaah that's clears that up then! They are 60Ls. Guess I'll convert them to cable clutches for RHD. Appreciate all the help!

Voloskovich just as an FYI, the 1.921 2nd gear drops 250-300 less rpm between shifts at 8000-8200 rpm. This mean seem minuscule but with the power and my car has this is a difference of 5hp. That is enough for me to fend off higher horsepower cars on short chutes.

Thanks Rallytwit, I hear ya! I'll be keeping an eye out for a mid-close box as that taller 2nd is certainly better than the std ratios. Will be behind a pretty stroppy A14 and also L18 w/ L14 crank so I think I may have the same situation as you too.

Expanding further on the 63 series box; the third gear is taller as well and one would need to check the ratios for the tracks that you run. On the 2nd to 3rd shift the 63 series with the closer ratios drops 400 rpm less than the same shift in the 60 series box. The 3rd - 4th shift for the 63 series box is 150-200 rpm is closer as well. Additionally 5th gear is lower so there is less of a penalty as overdrives go.

In my case the taller gearing means 4-5 mph higher speed at redline in 2nd and 3rd.

Quote:Could be either 60A (standard pattern) or 60L (dogleg)

Bottom: 60L, lower drain plug points straight back



Bottom: 60L has "smooth" tail housing on left side (60A has a large boss sticking out)



box 60L.. 60A.1 60A.2 63A.B210
1st 3.513 3.513 3.513 3.382
2nd 2.170 2.170 2.170 2.013
3rd 1.378 1.378 1.320 1.312
4th 1.000 1.000 1.000 1.000
5th 0.846 0.821 0.821 0.854
REV 3.464 3.764 3.764 3.57