Need second opinion for future rebuild

Ok all you performance gurus, looking for a second opinion on cam and lifter kits for best performance. This is for the AMC 258. Already going to go with the 4bbl intake but also need to figure out which carb to go with that. So here are my choices for the head rebuild. Looking for the most performance I can get while keeping it reliable.

http://www.summitracing.com/parts/CCA-K68-239-4/
http://www.summitracing.com/parts/CCA-K68-231-4/
http://www.summitracing.com/parts/CCA-K68-232-4/
http://www.summitracing.com/parts/CCA-K68-200-4/
http://www.summitracing.com/parts/CCA-K68-235-4/
http://www.summitracing.com/parts/CCA-K68-115-4/
http://www.summitracing.com/parts/CCA-K68-201-4/

Going to be picking up a 1980 CJ7 tomorrow rather than the CJ5 but its still got he 258 and plan on doing the mods in about a month so I'm still needing guidance from the fellow technicians on here.

How about the 4.0 head, Howell F.I., and a Comp or Crower cam? I know those are popular for that setup. I'm not a 258 guy so I can't give you specifics on lift and duration but from being around them I know that setup is pretty stout.

I'm sticking with my 4.2 head and have already looked at the 4.0 head conversion and its just not what I'm looking for. Trying to keep it all 4.2 but with just a little more power.

Take your 4.2 head over to Long's racing engines and have Jerry go through it he did a great job on my Dad's 4.0 head and awsome work on our SBC bowtie heads

paramedac wrote:

Take your 4.2 head over to Long's racing engines and have Jerry go through it he did a great job on my Dad's 4.0 head and awsome work on our SBC bowtie heads

What kind of money would I be looking at? Plus thats in SA, not here in Corpus, lol.

Quite honestly a 4.2 build would probably be more on the unique build. I would recommend taking the heads to machine shop that's local and have the heads opened up with some porting of the intake/exhaust valves and mill the heads a bit. That will increase flow through your heads while increasing compression. Than just buy the valves to fit. The machine shop worth it's weight will know your sizes and interchangeable parts and weights. If you want to kick it up a tad more, have them port match the new manifold at the same time.

Going with your list, the second one. K68-231-4. It has a power band 800-5000. Realistically, you won't go over 5k on that motor, but to start building power at 800 rpm is great for crawling and gearing options. .462/.485 is actually a good lift. If you get the head work done at a machine shop like the above post, you already have new springs and what not. The idol won't be out of control, nor your gas mileage. It would be a moderate build. Not weak but not balls to the wall.