Any advantage to these other than the smaller chamber? I'm thinking of throwing a set of these on my LS1 with an '02 Z06 cam and intake. I thought this would make a great low budget, torquey street motor. I'd love to hear some experts thoughts. Any idea what my compression ratio would be?

 

I went with Texas Speed's Stage 2.5 5.3 liter heads with their 224R cam. My understanding of the benefit of those heads is they are a bit cheaper than LS6's (that are comparably ported), and they have the smaller intake runners as you mentioned. When I bought mine a couple of months ago, they were about the same price as a set of Stage 1 LS6 heads, which didn't flow quite as well, or a couple of hundred cheaper than a set of Stage 3 LS6 heads, which flowed better.

If you are looking for great low end, I'm not sure if a Z06 cam is the best choice, but then again, if you are looking for a stock-like idle, you probably are a bit limited. My understanding is that intake valve closing and exhaust valve closing are key to your dynamic compression ratio, which will dictate lower rpm performance. I was seeking stock-like characteristics, but wanted some nice low-end, and I found that most of the higher LSA/low duration cams tend to leave a bit to be desired on the lower end of the rpm range. That is why I ultimately decided to accept a little lope and go with the 224.

Pianoprodigy on LS1tech.com has a DCR calculator that will tell you the dynamic compression ratio for a given setup. It uses Comp XE and XE-R lobes, though, so I don't know that you could figure what a Z06 cam would be, since it's not one of those grinds. Mine came out to around 8.6, which is supposed to be great for a street setup. My low end is awesome; 350ft lbs from 2,500 or so, peaking at 390. If you use that calculator and some hypothetical cam specs, just make sure you use 63 for the "Cylinder Head Chamber Volume". Good luck!