Gearbox failure

[philip r]

hello guys

i have a 306 with GT28RS turbo kit (dp engineering) and the gearbox keep break down, 2 months ago it was the second gear and now its the third.

the gearbox running with quaife diff and the ratios is 1-2.92, 2-1.85, 3-1.28, 4-0.95, 5-0.74 & fd - 3.79.

what can i do to keep the gearbox reliability? Replace it? with what? replace the ratios? from what?


best regards
phil

[cully]

ask Chris Lapit he is having similar issues I believe he is currently experimenting with HDI gearbox's

[philip r]

which HDI? 2.0 or 1.9?

[miles]

Use a better box, the BE box does not handle the power, You can try the ML or go for a custom Bacco Ramio box, Around €9500.00

[welshpug]

which HDI? 2.0 or 1.9?

there is no 1.9 hdi

[philip r]

Use a better box, the BE box does not handle the power, You can try the ML or go for a custom Bacco Ramio box, Around €9500.00

which models come with ml gearbox? can it be fitted into the 306?

[fatlapit]

Currently sorting out a quafie gear kit as its the only proven method of a gearbox staying together. The hdi boxes do last longer than the petrol boxes

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Oh and Bacco Ramio is alot more than 9500 if u look into them properly and thats only for the dog gearkit. The full fia spec sequential is 14,000 euro

[pug306driver]

spotted the 2 teeth and where they are from, but what is the blackish round thing they are on in the lower picture??

[Toms306]

Presumably just a magnet to pick them up.

The MA boxes have a magnetic drain plug but the BEs don't for some reason.

[fatlapit]

Be has a magnet in them

[Toms306]

Ah so is it loose then? Makes more sense to put it on the drain plug tbh.

[welshpug]

no not loose, it sits in a slot in the bottom of the main casing

[philip r]

is the ma gearbox internals can be fitted in a BE housing and using the same quaife diff and final drive?

[welshpug]

no, its all smaller and weaker.

[miles]

The Quaife is not rated for turbo power either,

[fatlapit]

But the quafie is the only tried and tested method. All other methods have failed including these special gears that also seem to be made out of very expensive fudge. Give mat a ring from pug 1 off and ask about his gearkit in his 205.

[miles]

Bet there's no warranty on it thou and it's a chunk to outlay, the case is not upto it either really, when you look at 8v to 16v cases you can see the extra strength, in the BTCC dog box's the cases broke so I would try the ML route as they can take a fair amount of torque and within a fair budget

[fatlapit]

its the next cheaper option than buying a full on 9k gearkit that also has no warranty.

[welshpug]

naah, cheaper is an ML conversion, see what happens.

[Xsikid]

naah, cheaper is an ML conversion, see what happens.

Keeping a close eye on this thread as gearbox and diff are next on the list for me

[fatlapit]

Ml isnt that much stronger and is a night mare from what i can see. Theres not alot of room for cables etc at the back of the bay plus custom shafts etc

[welshpug]

plenty of room, its on every v6 ive helped with.

shafts are easy

[fatlapit]

Do tell then mei

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Bearing in mind i struggle to get 3 gear rods to move without being super close to everything

[miles]

Cable's are dead simple, all of the 406 stuff fits and if anything free's up more room, the box's handle allot more than a BE, look at all the HDI's running them in various M varients with anything from 300nm of torque upwards, mines running 395nm without any issues at all, but how much space etc is taken up by the turbo and box size is impossible to tell, whats the ratings on the quaife stuff?

[fatlapit]

Enough for matts 205 not to blow the box and spooxs 205 turbo builds

[Ruan]

Are we sure that it's definitely the gears actually being too weak and it's not the casings flexing and allowing the gears to drift apart and then munch themselves?

I'll admit to knowing very little about gearboxes... However I've seen before gearboxes requiring bracing to stop the shafts inside moving apart allowing the force to be applied to the very tips of the teeth.

[welshpug]

youre probably right there Ruan, thats what causes the failures in the ma boxes once you swap all the original bits out, logic says youll experience similar issues with the larger box as you push the envelope there too.

[fatlapit]

Thats the biggest issue with a straight cut box

[Ruan]

youre probably right there Ruan, thats what causes the failures in the ma boxes once you swap all the original bits out, logic says youll experience similar issues with the larger box as you push the envelope there too.

I've never stripped one down properly or taken any real notice of the BE boxes in honesty, reckon there's any mileage in placing a steel ring possibly around where the bellhousing meets and also around where the end cover bolts on?

Might help hold the layshafts in place and stop them flexing apart under high torque, whether you'll get enough meat in there to make a difference I don't know... What you really want I'd guess is a plate underneath where 5th gear sits under the end cap to hold that part of the box together... Also a plate underneath the layshafts on the other side, not sure there's any possibility of anything in the bellhousing unless we can find a place to put a thread into to hold a plate...

Something around here - looks possible if it can be made low enough and out the way enough:



Something around where the input and output shaft goes here too - might be possible?



Wonder if it's worth just machining a steel plate that would sandwich between the end of the 5th gear cover and the casing?

[welshpug]

the later BE4 boxes for higher torque applications had a smaller bearing on the output shaft, so there was more material between the bearings.