Does any one have any suggestions on what cylinder head i should use for a 351C that i want to stroke out to 426ci? what i have been reading says that the 4v is good but so is the aussie 2v, but im not sure which one would be best to use?
I'm using 2V's on my 393; every 4V headed motor, strokers included, didn't hit peak power til at least 7000 RPM. Thats too high for a motor seeing any street use, IMO. Depending on what RPM you want to run, 2V's would make more power under the curve in the sub-6500 range (thats where I'll be shifting), with the peak at 6000-ish. Unless you're wanting to shift the motor at 7500, the 2Vs will have more under-curve area.
If you're using off the shelf pistons, you HAVE to use open chamber heads; the compression will be sky-high if you don't (but I don't know of any 426CID off the shelfers anyhow, only 408 and 393). If you're running custom pistons, have a D-shaped dish cut into them and use closed chamber heads.
IMHO, w/the 426 cubes, I would want the extra breathing ability of the 4v's...
Even if your peak hp is higher in the band, at least you'll have more of it up there.... the sacrifice of low end, in my opinion, is over exaggerated.
I don't have it in me to spin my motor to 7k; spinning turbo 4 bangers up that high gave me the willies, LOL. Although I do still toss around the idea of 4Vs due to the extra intakes and such available.
My SRP's look pretty similar, only no lower dish and they have an exhaust valve relief. With open chambers they get me 10.4:1, IIRC.
Honestly neither do at...at least not routinely....if you look at my chart though...the HP is just about flat from 6500-7000 so either the carb was holding it back, the intake peaked or something else....the torque was dropping fast so when I am 'on' it on the street I shift it at 6300-6500 anyway. The only time its hit 7k so far was on the dyno.