Twin cam knowledgable in Cardiff.

[JohnMorin]

What I mean is you must have some documentation stating what these figures should be. Do you have that? If so please post them.

[2cams70]

If you are using 420 cams use the Miles Wilkins method but with the 420 QED timing data. That's what I did. Some say the data supplied by QED isn't the optimum setup but I prefer to go by what they say at least for the initial setup given they developed the cam and should therefore know what the specs. should be. It seems that by deviating from the standard QED settings the differences are only minor and usually it's down to personal preference because like most things whilst you may gain in one area by having a bit of a fiddle you'll loose out in another.

[Bitsilly]

I will look at the QED method asap.
The only info I have is that I should set inlet at 100 and outlet at 106, although Rohan suggests more like 107 and 110

[Bitsilly]

Sorry, also that full lift should be 155 thou and 122

[JohnMorin]

Are you sure those fully lift figures are correct, they seem very low. As the cam designation suggests I think the lift should be 420 thou.

[Bitsilly]

A friend is popping over to have a look so fingers crossed.
Regarding the figures, no I’m not sure of anything, but I will check QED specs.

[types26/36]

The full lift of the cam is .420”
Inlet full lift is 155” AT TDC
Exhaust full lift is 122” AT TDC

[JohnMorin]

OK, I don't think you need to worry about that.

Which method are you using MOP or start of opening?

[Bitsilly]

The friend is Nick Stag who is doing me a big favour. He built the head and fitted the cams so I am going to step back and let him carry on!
He is such a good bloke, he lives over an hour away!

[Bitsilly]

Nick sorted it all out simply and quickly bless him!
Thanks for all the help and advice.
My main mistake was using a protractor which was basically missing a necessary set of graduations, so all my readings lacked somewhat!
Alls well now,
Cheers everyone

[rgh0]

I dont know what Nick Stagg thinks about the QED specified timing numbers for the QED 420 cam but the are clearly different (wrong?) compared to every other similar lift and duration cam out there.

cheers
Rohan

[Bitsilly]

I know. And I have read your comments and investigations. It was always a concern of mine.
I am happy that at least I have something to start with that won’t bend valves.
Also, Nick machined and prepped the block and built the entire head to a spec he always uses, and he always used the cams reprofiled by QED. He is also sticking to his practice after many builds.
So I’m happy to go with his wisdom at least until I get to a rolling road.