The V8 Owners Forum -

Each carb does 2 cylinders one side (outside two) and 2 on the other side (inner two). So a carb problem should follow that pattern.

Chris.

Speedy cables and Speedograph Richfield will do a 'correction gearbox' to go in the speedo cable.
Speedy cables probably your best bet.

Chris.

Is there a reason you can't stick to the GEMS layout?

On my Land Rover, I faithfully reproduced the OEM cooling system layout (from a P38 Range Rover), and have had no problems with engine cooling whatsoever.

Chris.

The H218 is a fast road cam, so probably a bit weak at the bottom end. I ran a 'Torquemax' cam for a bit, from the now defunct RPi. I think they just got it from Piper Cams though! That was very good I thought. But eventually it ran out of puff at 5000+RPM. But your engine is so different (mine was ...

Fluid level should be checked, warm, engine at idle, in neutral.

I think!

Chris.

The breather is just a vent pipe that is open.
I had my oil cooler (in a Series Land Rover) at the top of the radiator. No issues with drain back.

Chris.

I've got a 9.5" clutch from Helix, which is taking about 300BHP, and it seems to be about on the limit.

But it's in a Land Rover so it can put the power onto the road. I would have thought that a larger clutch would be fine because you'll just light up the tyres!

Chris.

Probably off a Jaguar.

Chris.

That's a nice early model!

Chris.

Is it still a 3.5?,or is it a 3.9?

Chris.

They aren't quite level, so that's normal.

I have overfilled one in the past, and it did spit it out of the breather when running. But once it had spat out the excess, it settled down. No damage was done.

But the quantities do sound a lot!

Chris.

There is no such thing as a good exhaust tune on a dual-plane V8 (e.g. Rover V8) unless you cross the pipes over the engine like a GT40. You would need 1,4,6,7 on one header and 2,3,5,8 on the other. Exactly like the inlet manifold on a twin SU inlet. Anything else is going to be imbalanced, (hence ...

If you pull off the rocker shafts and put a straight edge across the valves, are they all at the same height?, or have you got a low one?

Maybe bad lifters?

Chris.

The camshaft doesn't seem like an unreasonable choice:
https://www.pipercams.co.uk/product/v8bp270ib

I would advance the timing until you can hear it pink. Then retard a fraction. Forget the timing lights and all that crap. That'll give you maximum power from the ignition system.

Chris.

I would go to somebody like Rimmer Bros or Turner Engineering and see what options they have. Their most expensive option will be the best.

Chris.