Diesel Gearbox in a 172 ff

[D1CKY]

This question is outta curiousity.

I've heard that Gearboxes out of Diesel Clios can reduce the cars revs at certain speeds for a quieter drive. I.e At 70mph 2800rpm instead of 3000 and something rpm.

Is this true ? :S

And is there any Diesel Clios gearboxes that'd fit a 172 ?

If so what would it affect ?

Top speed and accelaration ?

 

[Matteh]

I mentioned it in another thread because im planning to put a 172 engine in a mk1, so can use any mk1 box I've got laying around!

On the mk1s its a straight swap of the boxes, imagine the mk2s must be similar? you wont be able to use a mk1 box though, cause of different mounting points and speedo drive iirc..

ratios were (@7000rpm) 35 70 95 140 168mph

meant in the valver u had to drop a cog if u want to overtake on the motorway, but im hoping the 172s low down torque will avoid that

 

[edde]

I've heard that Gearboxes out of Diesel Clios can reduce the cars revs at certain speeds for a quieter drive. I.e At 70mph 2800rpm instead of 3000 and something rpm.

Is this true ? :S

And is there any Diesel Clios gearboxes that'd fit a 172 ?

If so what would it affect ?

Top speed and accelaration ?

Yep you could fit it the revs would be chnaged a load idealy use the JC5 from the DCI 80 as its the stronger box same NM streght as the 172 box but realy the ratios would be huge for example using 7.2 redline gearbox would go to
1st 36mph
2nd 72mph
3rd 108mph
4th 144mph
5th 187mph

However at 80mph stock 182 box does 4k the dci 80- box would do about 3.1k its not to bad hp wise its still more than a dci would make at that sort of speed in top but its about 65% the power the 172 would normally mate that that rpm.

Top speed woulnd't be affected realy since the hp the engine makes sin;t enough you'd have to leave it in 4th to max out realy 5th would be more an overgear for cruising and could go quicker down hills flat out as you've gravity helping you out and won't kit the limiter.

Acceleration would be affected though would accelerate slower since when you chnage up ypou'll drop way more rpm than you would with the 172 box.

I mentioned it in another thread because im planning to put a 172 engine in a mk1, so can use any mk1 box I've got laying around!

On the mk1s its a straight swap of the boxes, imagine the mk2s must be similar? you wont be able to use a mk1 box though, cause of different mounting points and speedo drive iirc..

You cna swop as you said and use a Mk1 or 2 box only got to remember if you have a phase 1 1 172 or a very rare phase 2 that you need to get a box with a speedo output on it.