i have a 300-6 that i will be doing a lot of work on...here's what i've gathered for information so far...

deck the block
port and polish head
---how much port/polish should i have done?
bore cyl's minimum bore possible
4bbl carb
---390 holley? or???
true dual exhaust using EFI manifolds
--- what muffler system???
--glasspacks??
--flowmasters??
---what size exhaust pipe??
custom intake
---offy? or????
cam
---what cam should i use??? on this i am still lost....
pistons
---this also i am lost...any help or suggestions are good


i was told to look for a "crossflow" head for my I-6...where can i find one??? does it exist? as it was explained to me, the intake is on opposite side of exhaust...

MontanaFord

 

There are crossflow heads in existance for the big six, but there were very few of them made, and unless you had an inside line with ford, you have very little to nil chance of finding one in the wild. I only know of one, thats on a dragster motor...and i think i've heard of 2 more.

These crossflow heads were designed for UPS trucks back when ford was supplying the engines for them...but the project never came to frutition.

As for your build up, it sounds like its going right along with the standard stuff for a 300...i can give you advice on a few things tho.

If you are going with duals, 2 1/4 inches should work fine but no more than 2 1/2... as thats all the big six really needs to breathe.

An offy intake will work wonders, i couldn't tell you which would be best, but i'm sure someone else here will....

Cams...that depends on you...something decent would be a 270H or 260H...both of which are pretty mild and should do a street 300 quite well.

Pistons: I've heard that you can have your rods bushed and run 351W pistons which will open up your aftermarket performance parts selection for pistons greatly....you may also be able to use 302 pistons, but i'm not aware of what mods would have to be done to make these work.

Port & Polish... you really only need to take out as much as you need to smooth out the ports..... get rid of casting flash etc.

Also look into oversized valves...you might and i mean MIGHT get a little more power out of it this way too.

 

If you look at the post for 300 six for a dirt racer there is a link in one of the responses. The link takes you to a site that has a recipe for a high performance six.