20 replies to this topic

[KTS]

first gear to layshaft ratios are the same (31:15) but first motion to layshaft ratios are different (18:29 for S/GT and 20:25 for SC) which makes the effective ratio (i.e input : mainshaft) 3.3:1 and 2.6:1 respectively

[stoneface]

When I looked at the gear ratios I compaired road speed of the GT set with a 3.44 diff to std A+ set with a 3.2 diff at 4000rpm

 

If my maths was correct, there wasn't much difference except in 4th.

 

A+ with 3.44 diff and SCCR (Jack Knight) with 3.2 diff also included. I previously has the JK SCCR with 3.2 diff

 

A+ 3.2       GT 3.44      A+ 3.44         SCCR 3.2
19.3              19.7           18.0            27.3  mph
32.3              31.4           30.1            41.2  mph
49.5              48.6           46.2            56.4  mph
70.5              65.8           65.8            70.5  mph

 

I went with the A+ gearset with 3.2 diff.
 

 

[Aridgerunner]

Now that I have the 3.2 diff installed, where can I buy the correct speedometer drive gears? I've been searching and can only find the drive spindle.

Any help will be greatly appreciated.

Bill

[Shooter63]

Now that I have the 3.2 diff installed, where can I buy the correct speedometer drive gears? I've been searching and can only find the drive spindle.

Any help will be greatly appreciated.

Bill

I think if you tell people either what TPM your speedo is or list the gears you need in the wanted section you'll have more luck.

Shooter

[Aridgerunner]

That was a nice suggestion but I am not allowed to post in the wanted section. For what it's worth the speedometer is a 1280 TPM.

I'll continue the search.

Thanks

[babsbrown]

I have a1098 at +20, BP255, flat top pistons, stock 295 head, twin 1.25s, mg metro distributor with no vac advance, 3.2 diff, 10 in wheels, standard gearset. As is it's not a struggle to get underway but the torque isn't huge below 3000, rather as whistler's torque curve shows. It goes well above 3000 though. A 3.1 might be fine with a standard first but I'm not convinced it could cope with a close ratio first.

I also have a 1098+ 40 with 12g295 head 9.4 CR. 45d evo dizzy and evo001 cam. I also have the 3.1 FD and mine behaves exactly the same as above. If I could change anything on my car it would be that 1st gear acceleration.