Lude Generation

Benefits of flat face versus dished
When do you need to go oversize
When do you need to up rate the guides over oem
Under what circumstances would you need coated versus plain Titanium retainers (I'm thinking this is only for an engine build that will be driven hard a lot and do a lot of miles)
Any brands best avoided for retainers, valves and guides? (as in, not worth the extra money)
Does anyone change the seats, or stick with oem? (if staying standard size valves or course!)

Go!

wurlycorner wrote:Benefits of flat face versus dished

Archimedes. Dished valves should give a drop in compression/flat faced should give an increase in compression that's proportional to the volume difference between dished and flat faced?

Maybe the most mechanical thing I will ever post.

I didn't tried yet on a H22 head but on a B20A7 head i have installed bigger valves (+1mm) and kept the OEM seats, just remachined them to accord them to the bigger valves .

So i suppose it is possible to keep the OEM seat on a H22 head, just have to machine them ...

I would say if your going for more aggressive head, i.e cams, retainers etc...

don't skimp on the valves, like I did

dropped a valve but got relatively lucky, the stock valves on a 150,000 engine couldn't take it

I had supertech ones in the end, which I had no problems with

Aggressive head you say.

Donald wrote:Aggressive head you say.

no wonder your back

It's the only thing he's good for...