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Discussion Starter #1
Here's some pics of the Patriot heads the second time around, with un finished seats, supposedly ready for a valve job.
Here's what I started with (after re-doing the guides). It's hard to see, but I think one of the problems on these is that the seats are installed with the tops below the floor of the chamber. The arrows show the lip around the chamber where they cut a small counterbore raduis.

This is after boring the intake throats to size and blending the chamber.

5 angle intake cut w/ bowl already blended
 

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Discussion Starter #2
Here's after the ex valve job and the bowl blended, and some blending in the chamber. Notice the spark plug, though...the threads are covering one side, so...

...I had to relieve some material around the plug...

...and blend it in. Now the end of the plug is more evenly exposed.
 

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Discussion Starter #4
Here's the top side. Lots of sharp edges and casting flash. Virtually no deburring done by the factory. These drew blood the first time I picked one up. :mad:
Hard to see in this pic, but I've blended the oil returns and deburred all the sharp edges.

Loaded up and ready to rock. New intakes, customer's old (Ferrea) exhausts.

Here they are installed on a Gen6 509 with new ARP studs and Cometic head gaskets, ready for the intake and 1071.

 

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So, after your refining do you feel that the Patriot heads are a bargain over the name brands? I'm still considering them for my 496 build.
 

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Discussion Starter #6
So, after your refining do you feel that the Patriot heads are a bargain over the name brands? I'm still considering them for my 496 build.
It's hard to say. I'm still going through some valve trian geometry issues that I have yet to resolve. That's going to impact a lot of what I think.
 

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It's hard to say. I'm still going through some valve trian geometry issues that I have yet to resolve. That's going to impact a lot of what I think.
Keep us enlightened.
 

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Scott, aside from the deburring, is all the valve work pretty much what you would do with any head coming in for work, or did you have to go above and beyond with these? My GMPP/Eddy heads had a really bad valve job, as in almost none of the valves were sealing, and it had to be redone.
 

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Scott,

Thanks for the great info and pics. What camera are you using to take such nice close ups?
 

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Thanks for taking the time to put this up.
It does not seem like you had to put an excessive amount of time in them, but I am not sure what you do to any head you get, so let us know how you compare the cost vs time.
 

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hi Scott and welcome to the board.

you mentioned on another thread that these flow 380s after being worked. do you know what the final port size ends up as? it seems like they would be huge because I heard they already start out in the 330s. is this true?

also, what head do you recommend for a mild compression 496?
 

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Discussion Starter #12
Scott, aside from the deburring, is all the valve work pretty much what you would do with any head coming in for work, or did you have to go above and beyond with these? My GMPP/Eddy heads had a really bad valve job, as in almost none of the valves were sealing, and it had to be redone.
It's pretty typical for a head that comes with un-machined seats. I did have to spend more time in the chambers (with an extra large radiused top cut) due to the fact that the seats are installed as low as they are. The spark plug unshrouding could probably be left alone but these heads are going on a blown marine engine and I didn't like the sharp edge that close to the plug.
Sorry to hear about your heads. Were they new?
 

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Discussion Starter #15
Thanks for taking the time to put this up.
It does not seem like you had to put an excessive amount of time in them, but I am not sure what you do to any head you get, so let us know how you compare the cost vs time.
Other than having to replace all the gides right off the bat, the work was pretty typical. Like I said above, the chambers required a little work which is another operation on the S&G machine and some blending, and there was some work to do on the ex side when we went to the flow bench, but knowing that going into the next set would save time. Basically the learning curve thing...
 

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Discussion Starter #16
hi Scott and welcome to the board.

you mentioned on another thread that these flow 380s after being worked. do you know what the final port size ends up as? it seems like they would be huge because I heard they already start out in the 330s. is this true?

also, what head do you recommend for a mild compression 496?
Ya know, I totally dropped the ball on that one. I meant to measure a port, but this whole "ordeal" has taken months, so I really needed to get these on the engine and done!
Also, lets be accurate about our info. These flowed 390 @ .700 on the good side, but only [email protected] .700 on the bad. IMO that's a pretty big split, and one of the differences between a "good" head, and a "budget" head. Anyone who's tried will tell you it's no easy task getting these left and right ports to flow equally on a conventional BB Chevy. You WILL pull your hair out trying.
I don't think these ended up any bigger than the 2.25 valve job. The seat ring ID on these heads is already 2.100". I didn't go any larger than that with the throats on these, so the 2.300/bowl blend really didn't make these measurably larger than Patriot's 2.25 version. I'm sure that whatever they measured from Patriot would be within a few cc's of these.
 

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thanks. and as to your preferred head on a street/strip pump gas 496?
 

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Scott, if i were fully porting these heads, I would actually appreciate the seats being below the casting in the chambers. Makes it easier to blend in. The actually probably flow better after you had to do the extra top cutting. What was wrong with the guides or did I miss that?
 

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Discussion Starter #19 (Edited)
thanks. and as to your preferred head on a street/strip pump gas 496?
I think the AFR 305/cnc chmber is hard to beat with the right cam. The TFS oval responds nicely to a 2.25 intake and can make good power, too...kind of depends on your idea of "street" 496. I've had good results with the Canfield 310's s well. I know you can make 800+ on pump gas with a 496, but "stretable" is another thing...:noway:
 

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Discussion Starter #20
Scott, if i were fully porting these heads, I would actually appreciate the seats being below the casting in the chambers. Makes it easier to blend in. The actually probably flow better after you had to do the extra top cutting. What was wrong with the guides or did I miss that?
I guess that depends on the chamber, but for the most part, if my top cut only has to clean up around the top of the seat and it's flush with the chamber there isn't much "blending" to do. Unless you're trying to change the shape of the chamber, I'd have to disagree. Canfields, fore example, come with the seats sticking about .010 above the chamber so you can finish your valve job flush, as do most new heads AFAIK. This is how I would install a new replacement seat as well when doing a repair, so as not to alter the shape of the chamber.

AFA the guides, I asked that Patriot send me heds with guides and seats un-machined, yet they arrived with most of the guides at +.002" stem clearance (some close to .003") which was unacceptable. Patriot did send me a new set of guides, but I still had to R&R them.
 
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