Don’t just look at the speed in top as all 4 speed boxes are 1:1 helical or straight cut. It is all the other gears you need to look at. A SCCR box with a 3.1 CWP can make first gear fun and a right pain to use.
that standard set up is stronger than many people think.
remember the Metro turbo only changed the bearing size for the input gear nose in the transfer housing.
work out it all out before spending
for example if you have no torque below 3k a standard box means it would be fun until about 15mph while the MiniSpares clubman gear set raise it to about 20mph now if you live in the country this will not be an issue. But town/city traffic.
again I have no idea about how your engine will work but you need to consider it all. Is the 3.1 correct for the box you need?
The AC RS Cam delivers power from 1250 - 6000 RPM
From AC's documentation "In a typical example build (1293 to 1330cc) this cam will deliver 83 to 85bhp with a gas flowed head and 84 to 86lbft of torque with a single HIF44 SU and a typical stage 1 kit fitted. Power would rise to a typical 92 to 95bhp with the addition of 1.5 rockers on the same engine."
Before adding the SC, I will be porting my head and using Metro Triple collet Valves (35.6mm Inlet and 29.2mm Exhaust). I will also hopefully be fitting a set of AC's zero tolerance 1.3 Rockers. Weber 45DCOE with the long inlet manifold, LCB and RC40 Exhaust.
This should produce around 85 lb/ft Torque.
I have been advised that, in preparation for going Forced Induction, I should swap the 3.44 Diff to a 3.1.
So will the Eco Primary / Eco 1st Motion Gear on a standard A+ box DAM 5262, with the 3.1 Crownwheel be suitable?
The power band is that, but doesn't suit boosted applications. You need to reduce the valve overlap, not many N/A cams provide that as they rely on scavenging to clear the cylinder and draw air in during the exhaust stroke.
I spoke to AC and he said the Cam would be OK but the FI Cam would obviously be better.
Here are the specifications. Is the overlap shown? I understand that this occurs when both the Inlet and Exhaust valves are open at the same time?