cougarfan088

I plan on building a 347 here in the near future and was wondering what is available as far as ported heads. what is the best head out there on the market, I dont care which is the best bang for the buck but what is the best cylinder head in general?. who does CNC porting?

Portmaster

Depends on your goals. Steet car, drag car? I'm sure AFR ot Trick Flow would be your best bet. I'm a big fan of the AFR's for serious street cars. You can buy either CNC ported.

cougarfan088

Im trying to get as much HP as I can out of a 302 block NA. Heads are usually where you want to go after you have figured out yer cube situation. Who sells ported AFRs and are these ported from AFR themselves or are they ported at a performance shop?

mjr46

you can get what you need from AFR direct or use trick flow fast as cast heads......the sky is the limit on how much hp you can get out of a 302 block......now will it hold together?? most likely not once levels hit around 450-500......cap walk is the killer and keep rpm down

AdderMk2

go on TREperformance.com they have a promotion right now (i need to find the coupon code) but they are offerieng $200 off website price on all AFR heads

(I almost splurged and bought a set of 185's for $1200!)

mjr46

so do it heck at that price I might pick up another set

Az_bronco_rob

Just my 2 cents worth: my machine shop guy (old-timer with a TON of experience) told me that the weak link in the sbf is cap walk, just like mjr46 mentioned and the best way to beef it (the bottom end) up is by using a stud girtle. I was telling him about my plans to build a Mexican 302 and/or putting 4 bolt caps on my build and he said to just stud it and girdle it and it would be fine - switching caps was a waste of money.

Portmaster

One thing you might want to consider is the machine work to the block. You can pick up a good bit of power from a well machined block. A well machined block can also make more power because of reduced stress. Lighter weight rotating assemblys make more power and also reduce stress to the block as well. Chamfering the top of the cylinder will also help unshroud the valve especially on large valve heads and again make more power. Having oil shed coatings that won't allow oil to cling to the rotating assembly not only allows the engine to make more power but by keeping the weight off the rotating assembly the more RPM you can run and reduce stress on the block as well. There is a lot more to building power than a great set of heads.

As far as heads go CNC porting is great because it is able to duplicate the same porting program to each and every head and the CNC machine doesn't get tired or have a bad day BUT it doesn't allow for core shift of the heads from casting to casting. If you want absolute maximum performance a quality porter can do it better. Even on CNC head someone had to port the first head in order to write the program. Something has to be sacrificed to allow for the core shift. Only if you are looking for that extra 3-4 hp is it worth having them hand ported. It's also very expensive to have a set of heads custom ported because it is so time consuming. It's becoming a lost art.

cougarfan088

I wanted to buy beefier caps. does anyone know where I can get some from and the part#?. I planned on studding the whole motor. What exatly will a girdle do? is it the thing that you put under your lower intake manifold? that goes across near the lifters? does anyone have a part number to one?

OnyxCobra

+1 aint that the truth... Keith you should buy a set!