Opinions on SDPC CNC LS3 heads

[MIEngineer]

Yep...makes me wish I waited when I got mine!

I'm sure Greg/Pace has great pricing too as always

[CarRamrod]

Just to put this topic to bed, I’ve talked to 2 VERY reputable guys that I’m sure everyone here knows and respects and they both said these heads are great budget heads for a LS3 but not for our L76 engines. They both said that they have seen these heads on L76’s and tuned them and saw little to no gain in power. They both say you either need to buy something like Mast heads with the canted valves or get a company CNC port LS3 heads specifically for our engines.

I don’t want to post their names on here because I’m downplaying a product and I don’t know how that will effect them or who would get upset but I wanted to inform you guys. Just have your heads ported for the L76 or spend big money on some Mast heads etc.

Having said all of that I’m going to buy a stock set of LS3 heads from SDPC and send them off to have them ported.

[Andrewg8]

Have a set I could sell you for a fair price

[deb0650]

Regarding CarRamrod's comment...I don't see how the heads will perform differently on a LS3 vs. an L76 (assuming cam change and DoD delete). What we essentially have after the DoD delete is an LS3 with 200 cc's less capacity. Same intake. Essentially same short block. Essentially same ECM with the ability to have the same programming. Bore is not that different. Doesn't make sense to me. And I realize this is something you were told. So I guess I don't agree with the sources. If the heads were placed on a stock L76 with DoD and stock cam/lifters/etc., then sure, they would be different. But our modded shortblock is essentially and LS2 with LS3 heads and intake.

[CarRamrod]

It’s not the head itself. It’s the CNC port program they use on the head. It’s a great budget head for a LS3 but for our “LS2” motors there are much better CNC port designs out there specifically for our smaller bore engines. Stock for stock you’re right but we are talkin their CNC ported head.

[MIEngineer]

I think the heads with a cam would be a great match.

I know several who used the GM CNC heads on a 6.0 and made good power.

They are a good budget friendly head across the board. A friend of mine just sold his with these heads on it and it was a great daily driver with good power for a cam/head combo.

I don't see why even bothering to mention well respected people without a name is just sort of moot at that point. Maybe your contacts work for Mast or otherwise haha

Just like my friends car, everyone has different results and there are plenty of tuners out there.

Do what you want, what you can afford, etc.

[CarRamrod]

The point I'm making is that you can spend the same money on a head that's designed for our 6.0 engine and get more performance out of it. Not once did I say they wouldn't work or be total crap. I'm saying same money for a different head = more performance for the same $. Isn't that the game we are all chasing after all?

I'm mentioning "well respected people" to show that its not just my personal opinion on the heads but opinions of people who actually get paid to build motors and tune them. I don't do that for a living so I reached out to them to see their opinion. I don't know if they told me this in confidence or not and I certainly don't want to name drop and start a fire when they gave me their time and advice for free. They are on this board and if they would like to weigh in then they will. They don't work for mast or otherwise.

Its cute how you call me out for not dropping names but then use an example of a "friends car" to say the heads are good. We all know someone who did something that worked well. The question I'm raising is would his car worked better with a head that was ported for our 6.0L engines instead of the LS3? You don't know that and neither does he. But there are sure a lot of engine builders and tuners who think it would. Why not go out and do your own research? Why not call your tuner or engine builder? Please post your findings here and let us all know. Information is power so lets see what you come up with. Don't just downplay my research when all you have to go off of is a "friends car" that he doesn't even own anymore that had good results from 1 product who didn't try any other products. That's just silly and ignorant.

Let me state this again, the SDPC heads are good heads. There are people everywhere praising them and they did a fantastic job on the heads. What I am being told by engine builders/tuners is that for the same money you can make more power with a head that is ported for our 6.0 engines. Not just a standard out of the box ported LS3 head. The reason is that we don't have LS3 engines (unless you have a GXP). Us GT owners have a 6.0L. Buy heads ported for a 6.0. Not a LS3.

I encourage everyone to do your own research. This is the internet. Pick up the phone and call who you trust and listen to their opinion. This is what I'm hoping people will do. Not just believe that "so and so" had good results so this is it. I did research and I'm bringing it here to benefit the people on this board. Don't trust me? I understand that. The solution? Pick up the phone and call the Pros.