adduk

Can someone explain to me in a reasonably simple way how the torque figure is worked out on an engine build. I understand what it is and that it can be measured/calculated on the rolling road but do people actually work it out prior to the build of an engine based on parts they install etc.

I am building a zetec turbo (Silvertop) with Wossner piston etc and looking to run at around 320bhp. I have fitted an ST170 box and looking at clutch options but as the clutches are rated in torque figures i am not sure what a zetec turbo at that BHP will produce. If anyone has any figure they can share it might help me get an idea for what i need but i assume people don't just build these engines any guess the torque figures for the clutches or is it all just experience?

Stay safe.

Adam

scoooby slayer

iTrader: (4)

It depends at what rpm it makes the hp to determine the torque, the lower the rpm the engine makes hp the higher the torque will be

Torque is hp X 5252 divided by rpm

So if you make 320 hp at 4000 rpm

320 X 5252 = 1680640
1680640 /4000 = 420

So your engine is makeing 420lbft at 4000 rpm

But if your engine makes 320 hp at 3000 rpm then your making 560 lbft of torque

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stevieturbo

People take factory numbers, and then start dreaming as to how much more theirs might be.

Usually it's all based on fantasy

markk

iTrader: (2)

Experience, knowledge and understanding.

Rick

It depends on the boost profile and engine capacity as the main inputs. But 350lbft would be a ball park figure for your engine.

The 6 speed getrag isn't ideal for your application,the ratios are short and it's weak. Better to for an MTX box if you can.

adduk

I am already committed to the 6 speed box as i have it, the mounts are fitted and i have some Dave Mac shafts for it. Just need to sort the clutch and diff. The cars been sat for years before i got my head back into building it and the parts were bought a while ago. If i had the option now i would go MTX.