Hey guys,

So I've been a big fan of the 300 for a while now but I too know how much of a dog they are stock in terms of power. Much of this can be attributed to the very old and outdated cast iron head and top end design, after all these engines still had quite a bit of tractor tech in them. For most other engines this is not an issue, you can simply hop on your favorite parts website and pick up a set of aluminum heads that are simply bigger and better. However with the 300, as many of you know, this is simply not the case. To my personal knowledge there is not a single company that still makes 300 aluminum heads, or really any performance 300 head for that matter and custom from scratch parts that are that big can easily cost close to, if not reach the five figure price range.

For many, this is where the search ends, however I found this article on bangshift.com (https://bangshift.com/bangshift1320/...rd-inline-six/) that explains how one of their forum users managed to Frankenstein together 3/4 of two separate LS heads to fit on his 300 straight six and it actually worked! This solves all of the issues of the stock head from flow to material to finally putting the intake and exhaust ports on different sides of the head. Now obviously no one wants to drive around with a two piece cylinder head that is literally glued together, even the original creator had internal leaking issues with a custom plate and crazy strong epoxy.

All I could think about after reading this article was the potential that this setup had. I thought to myself "If only they made a v12 LS". I mean in theory that would solve the split head issue with all the LS head goodies at the same time. Then I remembered, they do make a v12 LS! Now sure GM never made one of these engines but a company by the name of Racecast Engineering (http://racecast.com.au/) produced a v12 LS engine that supposedly has the same dimensions as if you just added two more cylinders for each bank on a standard LS. While I know bore spacing and such is probably not exact, this seems like the closest solution so far to a killer head setup for the 300. Let me know what you guys think, do you think it could work?

 

The accumulative bore spacing difference of .080" will put the outer cylinders way off center of the cylinder bores.
The best you can do is weld 3 two cylinder sections together.
The pushrods end up outside of the block side cover so you need a special side cover to go with the heads.
All of this is presently being done by "WorldChampGramp".

Meanwhile Promaxx heads now has fully ported, big valve heads made from new 4.9 EFI iron castings.