7 replies to this topic

[majorslinn]

1996 spi mini sprite

i like to have Close ratio gear so i been doing some resarch but still not sure what to get? So my gearbox is 4 syncro a plus so i believe i need 18 teeth first motion DAM3167 , Laygears - 4 Synchro - 1275GT/'S' 22G1040 , 2nd gear 22G1094 and 3rd 22G1095. Is there any thing missing please let me know so i can buy some part.

Cheers

Christian Slinn

[rozzer1275]

I lot of people change the final drive diff ratio, so having the effect of changing all the gear ratios, cheaper option.
or drop gears.

[Guess-Works.com]

Two problems...

the close ratio helical gearset is an A series gear profile, so not only will you need a 1st motion gear (DAM3167) and the laygear (22G1040 or equivalent) but you will also need an A series 2nd gear and an A series 3rd gear, or basically a completely different gearbox... This I see you've already discovered.

Secondly, getting hold of a GT gearset is pretty much neigh on impossible, 1st motions have been unavailable for a while now, which means you're looking for either new old stock, or second hand.

There was a NOS one on ebay just a couple of days ago, http://cgi.ebay.co.u...tem=11034632809 and that was a seriously good deal @ £111.

I have been asked by many people ( from all over the world ) to try and source the 1st motion gear, and you'll notice that the winner of that gearset above was from Hong Kong.

So simply speaking, unless you already have the gears, then you may spend a while looking for them, and for not much more than I believe they will start to fetch money wise, you could probably buy a new straight cut close ratio gearset.

Edited by GuessWorks.co.uk, 11 February 2009 - 10:00 AM.

[Wil_h]

I don't know what you need, and frankly carn't be ar5ed researching it. Why not just ask the supplier? they are most likely to know what you need.

I do know though that changing the diff won't make the ratio of the gears relitive to each other any closer.

Edit: Better answer above.

Edited by Wil_h, 11 February 2009 - 10:01 AM.

[majorslinn]

So i cant used A plus gearbox for this conversion? I thought that just need these things 18 teeth first motion DAM3167 , Laygears - 4 Synchro - 1275GT/'S' 22G1040 , 2nd gear 22G1094 and 3rd 22G1095 will complete the converison. Aye i do know about 18 teeth first motion DAM3167 are quite hard to find/ get that why i am working on my A plus engine at same time as finding these part.

cheers

Christian Slinn

[rozzer1275]

I don't know what you need, and frankly carn't be ar5ed researching it. Why not just ask the supplier? they are most likely to know what you need.

I do know though that changing the diff won't make the ratio of the gears relitive to each other any closer.

Edit: Better answer above.

The original statment was 'I like to have close ratio gear' 'but still not sure what to get'

Yes changing final drive will give the effect of a close ratio gearbox in relation from the engine speed to the driven wheel speed, without physicly changing all the forward gears.

as said is a common cheaper option than changing all the gears.

have a look at guessworks excellent gearbox calculator.
http://www.guess-wor...nical/ratio.htm

[Wil_h]

I don't know what you need, and frankly carn't be ar5ed researching it. Why not just ask the supplier? they are most likely to know what you need.

I do know though that changing the diff won't make the ratio of the gears relitive to each other any closer.

Edit: Better answer above.

The original statment was 'I like to have close ratio gear' 'but still not sure what to get'

Yes changing final drive will give the effect of a close ratio gearbox in relation from the engine speed to the driven wheel speed, without physicly changing all the forward gears.

as said is a common cheaper option than changing all the gears.

have a look at guessworks excellent gearbox calculator.
http://www.guess-wor...nical/ratio.htm

Bollo x will it. The difference between the gears will remain at the same ratio what ever diff you have in. I have my own gearbox calculator to show just this.

[Guess-Works.com]

As Will says, physically it'll have no effect on the ratios of the gears, but what it will do is change the road speed achieved in each gear. Choose a longer final drive you achieve a higher speed in each gear, choose a shorter final drive, you achieve a lower speed in each gear. But mathematically the gear ratios are still the same.

Changing the gear ratios in respect to each other can ONLY be achieved by changing the gearset.

If you manage to find an "A+" variant of the input gear ( ie DAM3167 ) then yes it'll go into an A+ box with no modifications, if however you only find the A series variety ( 22G1371 ) then the case will need to be modified to fit the earlier A series 3rd motion shaft into. The difference between the two gears is the size of the nose bearing on the end of the 3rd motion shaft which fits into the 1st motion gear/shaft.