Fitting the Quaife box

[Mike Biddle]

Took longer than I thought it would!

 

Yes I did have to cut 12 MM off the input shaft and I did it with an angle grinder fitted with a cutting disc.

 

I also had to modify the gearbox mounting because the new box has a deeper rear section to accomodate the sequential mechanism, and it fouled the front portion of the mount where there is another identical set of holes, assumedly for a different box? Anyway, removal of the front section allowed the new box to go in nicely.

 

The standard gear lever is too long with the knob fitted because it fouls the dash on the downchange stroke,so i'm using it without the knob untill I can get the lever off again for modification which really needs to be done at a machine shop. This is no problem since the change is very light and a knob is only really necessary to make it look right.

 

I also fitted a lightweight flywheel, (2.1KG)five inch AP lightwieght clutch, and concentric clutch slave cylinder operating directly on the clutch cover. The mounting point for the master cylinder operating rod was moved down on the clutch pedal to give a little more lverage and feel, but it's still far too heavy and fierce so I have to fabricate a lever system to immprove that.

 

First impressions after two hours driving are;

 

The upchanges are sweetness itself, and very fast, paticularly when accelerating hard. Dowchanges are more difficult to get right, the revs have to be accuratly matched to avoid a lot of "clonking". I think this will be be easier when I get the clutch operation right, and while more precision is required, I will enjoy the satisfaction of achieving it in what is after all a very demanding car anyway.

 

The box is very, very noisy, in fact I think that there may be a problem with it. There is a lot of vibration and noise (enough for drivers of adjacent tin tops to notice)when cruising on a light throttle and on the overrun. I have never used a box with straight cut gears before, and I know they have a reputation for being noisy, but Im sure this is just too rough, any comments anyone?

 

More at a later date.

 

 

[Chelspeed]

Comments:

 

Caterham seem to have fitted all sorts of different gearbox mounts over the years, mines 1993 and only has mountings for the five speed box. I had to mod mine by adding a new mounting when I went for a four speed.

 

Quaife say they can supply the box with a shorter lever from the factory, did they know your's was for a caterham?

 

What size master cylinder have you got? You can adjust the force against movement by going up or down on master cylinder diameter, bigger diameter less movement but more force I think and the opposite for smaller.

 

Is yours a dog box or a synchro box?

 

My synchro straight cut boxes have always been noisy, only ever had complaints from other cars once though. The present dog box is much noisier - I think they all do that sir..

[Alex Wong1697456877]

The 2 cars I've tried with straight cut boxes both sound like they're rattling to bits. I think that's just the way they are. I know at least 2 other people who thought their box was faulty when they first put it in because of the noise.

 

Alex

[Marius]

Can´t wait to put the Quaife-box in! Congratulations Mike, I wish I´d be over there in the VAE, sun and sequential-shifts, one hour ago it started to snow over here. Did you get the clutch arrangement from SBD again? I just contacted Steve ´cause of a lighter flywheel. Was it worth the money, what do you think?

Njoy your 7, merry christmas!

 

Marius

 

[Paul Ranson]

My experience of Hewlands is that they are noisiest when noodling, I expect Quaifes to be the same. If it shifts well and is equally noisy in all gears then it is probably OK.

 

You should be able to upshift without the clutch, just apply pressure to the lever and lift (very) briefly. From the outside it won't be possible to tell whether you have a 'flat shift' or not.

 

Get a flat shifter mechanism. Just tweaking the lever while your right foot is hard on the floor is a big buzz.....

 

For down shifts the clutch is probably optional. If you're positive, fast and agressive with the shift everything should just work.

 

OTOH you may be needing new dog rings regularly.... I wonder what the lifetime of one of these gearboxes is?

 

Paul

 

 

[EFA]

Mike,

 

They are noisy as F**K when new. The noise dies down as you become more used to it.

 

If its working properly 5th gear should be noisiest with 1 2 and 3 about equal. 4th shoulod be much quieter.

 

The clutch will aslo transfer more vibration from the engine to the box as it does not have any take up springs as the one you removed probably did......

 

Arnie

[Chelspeed]

New dog rings?

 

Wishful thinking with a Quaife box I think. If it's the same as my four speed dog box the dogs are part of the gears themselves.

 

I guess having separate dog rings is one of the benefits of a purpose built competition box rather than a modified road box.

[Marius]

Mike, Steve sold me a gearbox now which has 1st,2nd & 3rd straight-cut, 4th is 1:1 so less noisy, 5th is semi-helical. The box is about 200pounds more than the "normal" but does not feature that excessive noise in 5th.

 

Marius

 

[Paul Ranson]

> If it's the same as my four speed dog box the dogs are part of the gears themselves. <

 

The bits you can change on a Hewland are the bits that connect the gears to the output shaft, that are moved by the selectors. I think they may be deliberately softer than the gears, so that they take the brunt of the wear. About UKP70 each. Every time you rebuild the box you turn the dog ring over so that it wears on both sides of the dogs.

 

Paul

 

[EFA]

I think Mikes box is a a synchro not a dog box. He uses it on the road - hence a dog box and the associated selection of gears when stationary problem is inappropiate.

 

In Dubai traffic there is always the risk one he may even get trodden on by a camel......

 

[Mike Biddle]

It's a dog box, and I think I,ve just solved the problem of the noise/vibration. The rear of the casing was still in contact with the lower steel cradle of the gearbox mount. I'll post again once I've tried it.

 

Quaiffe knew the box was for a caterham but did not advise that a shorter lever was available.

 

Marius, yes, the flywheeel/clutch came from steve, and there is a significant improvement in acceleration, but be aware that the clutch will be very heavy with very little travel between out and in if you just use the standard caterham pedal/master cylinder arrangement, assuming yours already has an hydraulic clutch, many left drive cars did. I just spent the last two days fabricating a set of levers to make the pedal lighter and give more travel, which also gives more "feel", making it much easier to use.

[Mike Biddle]

Okay, the bgearbox is still harsh and noisy, but now that it,s not resonating through the chassis through the mounting it,s now acceptable, and the car accelerates so well it's worth it.

 

Arnie, the danger with Camels is not being trodden on. If you hit one you usually take out the legs and the heavy body is then forced through your windscreen and crushes anything in the way. A lot of people have died this way, specially driving at night when they are very hard to see.

[Marius]

That´s why they put the "Camel damage your health and might kill"-stickers onto the camel-boxes all over the world...