1.6 16v v 1.2 16v Gearbox questions

[Martin_172]

got a couple of questions on the gearboxes for the above engines.

firstly before i go anywhere can both gearboxes be used on both engines? (eg. can you use a 1.2 box on a 1.6 or the other way about?)

secondly if the answer to the above question is yes, can the 1.2 16v box handle the power/torque from the 1.6 16v engine (what about if it was running 130bhp+)

3. what differences is there in the clutches? and are the flywheels the same, simmilar or completely different?

4. even if the 1.2 box fits ok and handles the power is it worth using it for the shorter ratios or is there not that much difference between the 2? (mine has a new box thats only done 8k miles on it so just wondering if i can use it)

and finally what about the 172 box, i assume this would be better on a tuned engine for handling power, but im sure i heard the driveshafts are different, does this just mean i need new driveshafts or would i need new hubs too? (is it possible to run a 1.6 16v with 172 box, 172 shafts, 172 hubs inc 172 front brakes and 172 coilovers?)

 

[Fred@BTM]

JB1, JB3 and JC5 boxes to look at are all identical

i'm half tempted to put my 1.2 16v JB1 onto the 172 cup engine

(i'm using the 1.2 driveshafts)

 

[Martin_172]

ah right so i can use my brand new driveshaft too.

what box would you recommend for the 1.6 16v fred, suppose i could use the 1.2 box untill it goes (if it goes!) but whats your thoughts?

 

[edde]

ah right so i can use my brand new driveshaft too.

what box would you recommend for the 1.6 16v fred, suppose i could use the 1.2 box untill it goes (if it goes!) but whats your thoughts?

Yep there direct fitments.

172 box should be the strongest or a diesel 80hp one as there JC5's

 

[Fred@BTM]

what are you planning?

 

[Andy_J]

beware of the speedo drives.. some are mechanical and some are magnetic pulses..

Martin, my 1.6 16v box is mechanical!

 

[Andy_J]

172 cup box has mech drive, non cup has magnetic. iirc

 

[Martin_172]

what are you planning?

1.6 16v lightned and ballanced bottom end, cams, headwork, exhaust manifold, decat etc

before it starts, this isnt a 172 vs 1.6 conversion question, and i already know all the details and would rather not hear them again!

 

[edde]

beware of the speedo drives.. some are mechanical and some are magnetic pulses..

Martin, my 1.6 16v box is mechanical!

Depends some cars use the ABS system anyway for speedo best to check.

 

[Fred@BTM]

use the 1.2 box!

 

[bmh.01]

Surely the 1.6 will shorten the liftspan of the JB1 significantly or the 1.6 wouldn't have a JB3 box in the first place ? Though if you've got it and the 1.6 hasn't got a box why not use it.
And having owned both there is very little difference in the ratios, revs/speed are very close between the two.

 

[Martin_172]

looks like its the 1.2 box im using then.

what else can be used on this engine from bigger engines apart from the 2.0 16v throttle body, if anything else?