I didnt see this info listed in the vortec sticky, Has anyone used these heads yet? Would these be too much for a 9.5 or 10-1 compression small block?

https://store.gmperformanceparts.com/store/gmProduct.jsp?part_number=25534446

I have a set at the shop right now getting a bit of machine work. The holes for the rocker studs are small and metric (I think it's LS size), so I'm having mine machined to fit 7/16 base studs. They're good looking heads, much thicker than stock Vortecs. Part of the reason for the runner size is that they're raised, just like the production Vortec. Mine are going on a 406 for my 'vette, should be about perfect. I think they're a tad big for a 355 but would work on a high strung 383. Too bad they don't make a "tweener" for someone needing something around 200cc's.

Thank you, the reason I keep asking these ?s is I have a 6 litre ls motor that I am collecting parts for to go in my car but this Will take a year or 2. in the meantime I'd like the car to have more power than it currently does while being able to recoup some of my money, by selling the parts I buy, in the future. Thanks for all the opinions, past and present.

I didnt see this info listed in the vortec sticky, Has anyone used these heads yet? Would these be too much for a 9.5 or 10-1 compression small block?

https://store.gmperformanceparts.com/store/gmProduct.jsp?part_number=25534446

These are great heads, a little pricy, But for what you might want to do the stock vortec's would work the best in most applications. Some guys are making 500lbs. tq. on 400 sb with the stock vortec heads.

Vortec style ports can get away with having quite a bit more volume than a normal Gen 1 head without losing any drivebility because they are really narrow and really tall, like the cathedral-style LS heads. That way you can keep velocity up as well as have the extra volume when you need it.

I'd say go for it, they sound like an excellent head for a bigger street engine (I'd say a 350 would be the smallest motor those heads should be one... probably best suited to a 383 or 400, but a 350 would be alright too.)