Chamber size for iron head stroker

yellow rose said

If you look and see what most of the newer combustion chambers look like, even for N/A stuff, you can see they are going back to way "softer" chambers. Softer is hard to describe, but you know it when you see it.

And again, I'm asking how much timing do you run with a Hemi or a magnum? Every magnum headed deal I've done is 34-36 just like any other wedge with decent plug location.

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I imagine what you mean by "softer chambers". A lot of **** out there ...and I haven't seentit'tall...but not much softer than a 273 or mag before it's an open chamber again, that is in the wedges we're working with here. Dont run a hemi or a mag outside a stock 5.9 in my pickup.
Example: I ran 28 total timing max with 25 being ideal/smoother on pump 91...100 octane was more like 28-30 total in my 410,l cid small block
9.9 comp 8.8 dynamic. Cranked near 190psi
It hated over 30 degrees no matter if the octane was there.
Just enough octane the motor requires is all you need. Thats example is a lil outside the box but it's the same dictating chamber. Before I forget to say this.. just build for the octane anymore if you trying go for it... focus there so you end up fkd and rattling when you put your foot into it....but really.. anymore octane than the tune requires is going to burn slower...and need "more timing" .Maybe that's what's happening, maybe not... but if the designed chamber is happy with around 30 degrees when all is right "stars aligned" ..then you wont need that much.
Stock stuff likes 35-36 ime, but we all know that motor is not a true blueprint piece and definitely not optimized for that chamber/head nor its potential even in stock as cast form.