Shelby GT350 R heads done by Valley head service

[BILL-C]

I can’t see any benefits to making 1 chamber bigger than rest. The bore spacing is off a little also. I think it’s just mistakes in the molds. Nightmare to CNC port stuff like this.

[Dan Timberlake]

My shop is currently in the middle of a rebuild on the 289 for one of the extremely rare 1966 race mustang coupes built by shelby. The heads are stamped "ported by valley head service canoga park. calif." The intake seats are 30* on this set. The other 3 sets we have done over the years have always been 45*.

Bill ,
That was "the thinking" back then by some of the Ford camp. The original C6FE GT40 heads ( that replaced the ported R Model head) had 1.875 intakes with a 30* seat. The Le Mans cam they ran was only .520 lift. They were all about low lift flow LOL. Most guys update them to 45* on the first refresh. Valley and Mondello were by far the two most popular porters SAI used. They tried everybody here in the So Cal area at least once looking for the best. I've seen them from Lockerman, Slover, and Fudge.

======================

RE: 30° seat low lift flow thinking

Like 30:50 to 33:: here ? -
https://www.youtube.com/watch?v=ow5cGV7bXCw

[gtcs3085]

We have built a few of the Paxton blower equipped gt350 289's in recent years. That carb hat is not engineered very well and causes huge fuel and air distribution issues. We have used o2 sensors in each individual header tube , egt probes in each tube, and spark plug readings to diagnose issues, and hand made air deflectors fitted into hat to fix problem.

Putting a small stainless mesh air filter inside the bonnet can be worth sizable power gains. Helps straighten out the tornado in the air hat.

Curious what filter you used?

[BILL-C]

C6FE heads have more potential than 289 head. Charlie can probably get 260 out of one of these castings, but I get scared easy! If anything I build develops a leak , then I have big problems. My stuff has to withstand big time abuse and live for a long time without cracking or seeping, so I keep the castings a little thicker at the expense of that last little bit of flow. If I have to do stuff over again free, I can’t pay the bills.

We have started making the C6FE gt-40 heads again off of the original ford tooling. We made all new machining fixtures to locate the machining on the castings with the emphasis on locating the intake bowls for best flow potential. Prototype just flowed 260/ 198 cfm with 1.94/1.60 valves.

[Carnut1]

C6FE heads have more potential than 289 head. Charlie can probably get 260 out of one of these castings, but I get scared easy! If anything I build develops a leak , then I have big problems. My stuff has to withstand big time abuse and live for a long time without cracking or seeping, so I keep the castings a little thicker at the expense of that last little bit of flow. If I have to do stuff over again free, I can’t pay the bills.

We have started making the C6FE gt-40 heads again off of the original ford tooling. We made all new machining fixtures to locate the machining on the castings with the emphasis on locating the intake bowls for best flow potential. Prototype just flowed 260/ 198 cfm with 1.94/1.60 valves.

That is awesome Bill! Good luck with that project!

[piston guy]

C6FE heads have more potential than 289 head. Charlie can probably get 260 out of one of these castings, but I get scared easy! If anything I build develops a leak , then I have big problems. My stuff has to withstand big time abuse and live for a long time without cracking or seeping, so I keep the castings a little thicker at the expense of that last little bit of flow. If I have to do stuff over again free, I can’t pay the bills.

We have started making the C6FE gt-40 heads again off of the original ford tooling. We made all new machining fixtures to locate the machining on the castings with the emphasis on locating the intake bowls for best flow potential. Prototype just flowed 260/ 198 cfm with 1.94/1.60 valves.

Great news Bill . That is 20 better than the BEST set of the 7 sets I've owned flowed 240 also done by Valley. I know flow benches vary but that is a great number. I trust you also thickened the outer casting above the head bolts to eliminate cracking there.
Randy

[BILL-C]

C6FE heads have more potential than 289 head. Charlie can probably get 260 out of one of these castings, but I get scared easy! If anything I build develops a leak , then I have big problems. My stuff has to withstand big time abuse and live for a long time without cracking or seeping, so I keep the castings a little thicker at the expense of that last little bit of flow. If I have to do stuff over again free, I can’t pay the bills.

We have started making the C6FE gt-40 heads again off of the original ford tooling. We made all new machining fixtures to locate the machining on the castings with the emphasis on locating the intake bowls for best flow potential. Prototype just flowed 260/ 198 cfm with 1.94/1.60 valves.

Great news Bill . That is 20 better than the BEST set of the 7 sets I've owned flowed 240 also done by Valley. I know flow benches vary but that is a great number. I trust you also thickened the outer casting above the head bolts to eliminate cracking there.
Randy

It's great to hear from you again Randy! my flow bench is calibrated properly and i'm totally confident in the numbers. We changed the grade of cast iron from 35 to 40 with brinell at 210 +. One of the keys to fixing the cracking on the exterior above the head bolts was to limit the pours to no more than 8 heads at a time.The molten cast iron in the pot would start to cool and not pour correctly as soon as the temp cooled even the slightest bit. This resulted in thin spots on exterior around exhaust ports and under rocker studs. The last batch we finished this week are the best we have done.

[piston guy]

That's great news Bill. Now I just have to take out a loan to buy a pair! LOL I'll be in touch. Good to hear from you too.
Randy