Chopshop85

iTrader: (4)

I had a thread going on this somewhere but can't find it. I think Rogey was asking what I went for in the end?! not sure... anyway..

It looks like I will finally have my IB5 gearbox finished next week.

In the end I went for Ka 1.3 gearset and a 1.7 puma Final Drive (3.82) Which should give me as close as possible std RST ratios:

-Ka 3.15 1.93 1.28 0.95 0.76, FD 3.52
-RST 3.15 1.91 1.28 0.95 0.76, FD 3.82

Still not 100% on this though as it turns out nearly every forum I've looked on has different info. Especially when it came to the ka 1.3 final drives.

I'm using the bellhousing from a mk5 diesel for the cable clutch operation, and the main box housing from the Ka 1.3 as this will allow me to use the BC reverse switch mechanism so I don't have to faf around changing the plugs etc..

UPDATE: On closer inspection I cannot use the Puma final drive. It has much larger width teeth with matching pinion, however, the diff is 2mm smaller diameter than the ERST slip diff so it wont bolt to the crown wheel. So I will end up having to use the KA 3.58 FD

Gadget

Whats the final drive if you were to use the KA one?
Was thinking of using the complete KA box including the hydraulic clutch on my fiesta rst track car

Chopshop85

iTrader: (4)

According to the ford parts catalogue at a local gearbox specialist, the Ka IB5's come with either a 3.52, 4.06, 4.25.

Karlos G

iTrader: (4)

1.3 Ka's are supposed to have either 3.59 or 4.06 depending if they have PAS or not, but all the ones I've had have been 3.59 (I always count the teeth and calculate the FD to check before fitting) which is spot on, not too long and not too short, couldnt tell the difference between that and a stock RST box.

Chopshop85

iTrader: (4)

See the KA I got had the 3.59 FD (not 3.52 as I thought), and the diesel box had a 3.52 FD and I've heard people say the diesel box is too long which is why I opted for the 3.82 puma FD.

botters

iTrader: (2)

seems a lot of effort for a box that is still as strong as hot chocolate

Chopshop85

iTrader: (4)

Its a lot of effort yes. But in total it has cost me less than Ł200.

Have you had bad experiences with the ib5?

Karlos G

iTrader: (4)

To date i've not broken an IB5, running a 270ftlb CVH and nearer 300ftlb ZT... BC's I broke 6 of at around 200ftlb... As I've said many times it's not about the design of the box really (although IB5's have more webbing which does help with flex) it's more down to old brittle metal from years of heat cycling and fatigue, throw a 30k mile box in thats only a few years old and they seem to hold together well.

As above they are cheap as chips too, I pay no more than Ł35 a box and drop an LSD in, job done!

Chopshop85

iTrader: (4)

Also you need only like at the bearing size and pins to see the difference.

BC:


IB5:





Plus my car is just under 200bhp so I should think it will last better than a 100,000+ mile old BC box

zippyobrien

iTrader: (2)

I broke a couple of ib5s in my puma engined fiesta.

Both cracked around the diff area and shit the diff out. One out the top of the box, and one cracked and went inside the bell housing, fucked the clutch aswell that time.

One I broke launching it, and the other sort of locked up on a hard 2nd gear corner.

Chopshop85

iTrader: (4)

I'm not under the impression the IB5 is bombproof. Its just a lot better than the BC.

I think my mechanical sympathy will help matters as well.

zippyobrien

iTrader: (2)

Oh of corse. But I broke two with 130 bhp and 130 lb/ft

Not sure I'd want to chuck 230 bhp and 250 lb/ft through one.

Not entirely sure they appreciate being revved to 7500 rpm