Re: Dart vs AFR heads on HP 500
 

I'd say the Dart's, Brodix, and AFR's are probably all probably pretty close when it comes to a top quality CNC ported head. Did I miss any???----Canfield, Pro Topline?

Probably the main reason I chose the AFR's is because of their low lift flow numbers up to .600" lift....especially with the smaller 2.25" intake valve on their 315cc head. My friend with the same boat as mine (32' Active Thunder) who has supercharged 556cid engines just shakes his head in comparison of how well mine runs compared to his. And I am right there at his side from 3000rpm up to the top! Not too bad from a little 315cc head on a big ol' 565cid naturally aspirated engine with a little hydraulic roller cam that idles at 600rpm in neutral. I'm really starting to have a lot fun with it! :)

Re: Dart vs AFR heads on HP 500
 

I have always been partial to AFR because they seem to make the most power on any given combination, so it's good to hear that their numbers on the CNC heads are close to their published figures. I guess flowbenches are like dynos, every one gives a little different reading?

Jspeeddemon:
How fast does that 26' Daytona run with that combo? Must be a beast!

Re: Dart vs AFR heads on HP 500
 

Fantastic thread.......

Re: Dart vs AFR heads on HP 500
 

would this work on 500efi's as well...heads, cam and a computer remap ?

Re: Dart vs AFR heads on HP 500
 

Here is some more Jim Valako work. This hand port head was used going to be used as the basis for developing a marketable CNC cast iron head. At the end, we scrapped the project as we didn't see the commercial value.
At this point, Jim then hand ported a set (second set being completed now) based around be best ports on the head we used for the port development. Jim's results were confirmed at Flowmotion, TX.
The final ports we picked are highlighted. These heads supported 800+ HP with 505 CID at Keith Eickert's. Not bad for cast iron!
Want a set? Call Jim V.

Re: Dart vs AFR heads on HP 500
 

BenPerfected -

Wow !!!! :D

Re: Dart vs AFR heads on HP 500
 

Good info here

What intakes are you using with the AFR's?

Mark

Re: Dart vs AFR heads on HP 500
 

Mark, There are a few different intakes that would probably work well, but I am using the Dart single plane intake with 4150 carb base, but I believe they can be had in the 4500 Dominator base as well.

Re: Dart vs AFR heads on HP 500
 

Mark did you port match the intake to the heads?

Thanks
Mark

Re: Dart vs AFR heads on HP 500
 

This is in no way a negative comment about any engine builder on this website but there have been times when an engine builder has installed a catalog cam in an engine and called it a custom-ground cam after grinding off the original cam company's numbers. The cam specs become "top secret" when these guys are asked to supply the specs for future reference. The guys that do this aren't usually in business very long.

As I said, this is not a slam against any engine builders here on OSO. The engine builders on OSO now have been here a very long time and have excellent reputations.