I am looking for the most power on my 408 twin turbo Dodge. The limiting factor will be 91 octane pump gas. The present cam is a 232-232 @ .050 with a 549-549, it is ground on a 110 and installed +4
The cam I am considering is a 224-224 @ .050 with 573-573, gound on a 113 and installed straight up.
Which will make more power being that 91 octane is the limiting factor on cylinder pressure?

 

I would go with the smaller of the two. You'll make about the same power with about 2psi more boost, but quicker spool and better drivability.

 

If you order a new cam, get it as close to 0* overlap as you can. the 224/244 you mention is probably pretty close, where the 232/232 probably has quite a bit of overlap (judging from the lsa's). The rule of thumb is intake + exhaust / 4, so the small cam = 448/4 = 112 lsa minimum, while the bigger cam should be 464/4 = 116 lsa minimum.

With that in mind, more LSA = less cylinder pressure, smoother drivability, lower power curve (in rpms), more torque, etc. For a turbo, all of those things are good things.

I personally think that the 23x range is pretty ideal for turbos on larger cubes. I'll be running my 236/230 in the new 427.

 

If I understand things correctly, the cylinder pressure/compression reached is what determines the limit on 91 octane. With the turbos it is easy to add/subtract boost in order to reach the max point. With that in mind does a larger duration and lift cam make any more power than a smaller one, or does the max cylinder pressure/compression point once reached with both cams produce the same amount of power?

 

To expand on your thoughts, the 224 cam on a 113LSA will have -2º overlap. The 232/232 with 110LSa will have 12º of overlap. I'm not a fan of the formula for figuring out what LSA you listed...it does not take into consideration anything about valve events which is what determines where your powerband is, what octane gas you need at a given static compression, etc.

I do agree that with larger cubes, a 23x duration camshaft is in the right starting neighborhood for intake duration.