luke19790_3

how much power will a standard bc box take?

botters

iTrader: (2)

they will break at standerd power mate to be honest and anything over standard they are a ticking timebomb lol. fit an st170 , focus rs or escort rs2000 box with an lsd and fit and forget

darrenb16two

There shit boxes but a decent one will take 200bhp for a few thousand miles

stuart collins

iTrader: (7)

ive run 3330bhp through standard 1 and didnt break , changed to big bearing box and went straight away its luck of the draw with them really , i have broke 1 at 180 bhp in a different car also

Beach

What cam where you running for the 3330 bhp run Stu ? pmsl

Mines just shat its pants at about 180 bhp without any hard driving!!

Adam.

I have just had one built with uprated bearings and have done about 1000 miles so far with no drama thats with 196lbft.......i am waiting though

studabear

mine will be a ticking time bomb when the zt is in. Gearbox recently rebuilt too.

jonny s2

iTrader: (12)

as said luck of the draw, traction/grip could be the issue, as 3i or diesel boxes tend to last, with no lsd, mine s2 box was spot on upto 250ish

luke19790_3

heard someone say they had 300bhp+ zvh with a standard bc box. been running this box for over 11 years with no issues.

doga-ot

iTrader: (1)

S1 boxes are alot stronger In my old rst zvh running 346bhp i replaced 2 series2 boxes then tried a 1.8. Box then a new diesel box all detonated within few days S1 box lasted till i sold car it was still ok

muz

I don't think S1 boxes are any stronger, you just got lucky with it. I think I'm right in saying the BC box is a standard spec 4 speed box with a 5th gear banged on the end, and as such, is built to handle low power. The BC box is inherently weak due to having a flexible casing which destroys the bearings under load. Also, main shafts have a habit of snapping, gears sheer teeth. They aren't built for big power.

DixieTheKid

iTrader: (2)

As above, they are crap as standard. I broke loads!

Diesel box with a LSD is the only way forward without spending big cash.

series_one_rst

they're chocolate mate. blew 4 in 18month at 150bhp in my old s2. main shaft every time. crap boxes. had upgraded bearings machine in to try prolong the inevitable . next time mtx is going in.

Karlos G

iTrader: (4)

The box's are exactly the same bar the S1 has a 6 bolt LSD and the S2 is an 8 bolt...
Spot on!
Diesel box is again exactly the same so no stronger.

IB5 is the best you can do for very little money.

milesy23rst

iTrader: (16)

There's a bloke on the rsoc in the s2 room reckons he's running 286bhp with a standard box for 11 years

Neil.

He might have done....but how many miles has it done, and how much abuse?
If it's being claimed it's done XXX launches and trackdays, it's bollocks.

I've spoke to people who have made big claims of having boxes in for a long time, but the actual amount of work/abuse it has done is minimal. You can run a weak gearbox for years if the car is just sat about and polished.

J1mbo

iTrader: (1)

I did big bearing conversion on mine and it did a good few thousand road miles on my 250/250 engine, I put my 303engine on it and it lasted a mapping sesh then ripped the teeth clean off fifth gear when I loaded it up on the motorway, went mtx and was good as gold!

essexRSTSouthend

Ive known so many people blowing these boxes up but mine has been fine since ive owned it but do feel it might need a rebuild soonish. It ran at least 40kmiles on 172bhp with 184ish torque before i owned it. Since then its been running just over 200bhp with around 215ish torque for nearly 60k.

Oranoco

People get so caught up in the power when it's the torque that kills boxes. As somebody said on a limited budget the best you can do is an IB5 with the LSD dropped in.

My 260bhp, 250lb/ft S2 has had a CTS box in for years now and prior to being laid up was used on track and hammered at Brunters and Santa Pod.