Well, I just finished my "ordeal" with Patriot, and all I can say without a doubt you get what you pay for, which in the performance cylinder head world, for 990.00 bare, isn't much.
I purchased the first pair of Partriot 320's through Competition Products, bare, in late May. When I opened the box, I wasn't sure what I was looking at, but I immediately had some questions. The first thing I saw was that the valve job was so deep, that the head of the valves were below the top of the seats on both the intake and ex. I'd say the valve job was at least .200" deeper than it needed to be. In my experience, this was in no way a good thing. Next thing I did was check the guide clearances. No surprise there, but there wasn't a guide with less than .002", and some were over .003". They were rough, bumpy, and certainly not straight or even in any way, shape or form. On that basis, I rejected the heads. I called Patriot and I talked to Gunnar and Chad both, and of course no one knew how the guides could possible get that big, and well, the valve job was that deep to, and I quote," get the installed height", but there didn't seem to be a problem with it from their standpoint. Their "5 angle" valve job was non-existent as well. The bowl blending in some ares came right to the bottom of the 45, but no where was there any more than one more angle below the 45, and what looked to be a 30 on top. At best it was a 3 angle, and in some places only two.
I said I was returning the heads, and based on the guides alone they agreed, and I then ordered a set from them with guides and seats installed, but please, no machining. At this point I'm still going on the fact that these heads flow somewhere near what they advertised, and want to give them a chance. I know there was no way the heads I received were going to have any where near the advertised flow numbers with the valve job they had, but I thought if someone was to do a decent valve job, they might. The ports looked decent, and the casting quality was on par with the price. Of course this is costing valuable time and I have a customer on a deadline, so time is of the essence here. The second set of heads show up and the first thing I notice, again, is how deep the seats are installed in the heads. A valve job that only gets right to the top of the seat is still going to be sunk in the chamber requiring extra work to unshroud the valve. Oh well...it is what it is. Next I check the guides. OH MY GOSH...they're already out of spec. All over my min. and some as much as .0025. So much for installing and not touching them. I called Patriot and again, no one there knew how the guides could POSSIBLY get that big. Why, they don't even have a reamer that big in the shop! Now I'm a little tired of this, and after paying 170.00-some dollars for overnight shipping so I could get my customer up and running in time, the heads are not usable. Patriot did send me a new set of guides, so I had to wait on those to arrive, and then R&R the guides. I was finally back to where I was supposed to be a week prior, and finally got the guides sized and got the valve job done. Of course, the customer missed his deadline for having the engine, but that's another story. When I ordered the second set of heads, I was asked if I wanted the decks cut to size the chambers to 119cc, and I said yes. Check the chambers after finishing the valve job- 130cc's. Guess they forgot. More down time and cost to get them to the machine shop and have them milled.
SO...heads done, bowls blended, nice crisp 5 angle intake, radiused ex, all ready to go. Now to the flow bench. Well, no surprise there, either. Even with getting the valve job as high in the chamber as I could, using a very generous radius on the tops to unshroud the valves, and blending the chambers and bowls accordingly, I couldn't come close to their advertised low lift numbers. WUpper lift numbers were OK...with a 2.300" intake, I was able to get 390cfm @ .700 on the good port, but it fell on it's face at .800" back to 378 and got real turbulent with the swirl jumping to 3100. The bad port was another story. It only made it to [email protected] .700", and did the same thing, falling on it's face to 345cfm @.800" with the swirl going to 3800. Neither of these ports likes .800 lift, so I can see why Patriot only shows flow numbers to .700. The ex wasn't as bad on top. I was able to get 287 @ .800 with a pipe, but the low lift numbers still weren't close to Patriot's. Now in their defense, Gunnar did tell me they used a back cut intake on their flow test, and I didn't, so I'm guessing the low lift will pick up some after that change. On the exhaust, I worked the throat and radius under the 45, and laid back the chamber some more to unshroud the valve and it did pick up some. Still, the best I could get at that point wasn't what they were advertising. I think with both ports, having the valve job as deep in the chamber to start with is the main downfall AFA low lift numbers. Obviously raising the valve job helped the ex on top, but the low lift still suffers. The spread between the left and right intake ports is bothersome, and the fact that they fall off at .800 is also. This shows some fundamental design flaws in the port. Maybe a guy could spend a day on them and fix that...maybe not. It's easier to find an improvement somewhere in an ex port, but not always so easy on the intakes, especially left vs. right.
One other thing...rocker geometry. On a std. deck Gen6 block, I came up with pushrods longer than any other conventional BB head I've ever done. I use the Mid Lift method to determine pushrod length, and on the intakes I came up with 8.93", and the ex pushrods need to be 9.78". I don't know what the deal is, but there's something strange going on there. Part of it is the valve depth, but that might be .100" at the pushrod if corrected. The roller is pushed quite far out on the valve tip @ mid lift which says there are some issues with the lay out of the head. I'm also only at 1.900 installed height, and I know Patriot was advertising 2.00" installed height. Why they would want that, I don't know.
So, there's my experience with Patriot. I'm not passing judgement nor am I going to "rate" the heads or the company. They were always polite and answered all my questions, and were willing to work with me on the problems. I'm not sure that the right hand knows what the left hand is doing there, but honestly, the cylinder head business is a tough one. For $990.00 for a bare set of heads, like I said, you get what you pay for, although I'm not sure it's what you expect. I think in the end these heads are going to work fine, and give good performance and reliability. These aren't Canfields or Darts or anything comparable, but if that's what you're expecting, I'd say that's unrealistic. I also know from my own experience, I won't buy an assembled set of heads from anyone, and even bare heads need to be carefully inspected. Patriot claims they've had no complaints from any of their customers on any of these issues I've raised, but 1) what else are they going to say, and 2) how many guys actually inspect their heads, look at the valve jobs, check the runout, check the guide clearances, measure the chambers, and put them on a flow bench?
All I can say is buyer be ware.