Dart LS3 pro1 heads
 

Ive been going back and forth on parts choices for my dry sump ls engine. Im pretty sure im going with the Dart pro 1 ls3 head. I am looking to turn just south of 8000 rpm. My plan is these heads
ls9 block with a callies 6.2 litre rotating assembly at 12to1 compression
gm performance intake
holley hp 750
a hydraulic roller cam with stock ls3 rockers. I know but there are a ton of nascar spec engines that run this setup and are very reliable.
Does anyone have any experience with these heads? Ive seen a few big inch builds with 750 plus hp on them.

I know Borowski Racing Is a Dart dealer and they do their own CNC program to them and get huge flow out of them. So does Butler LS. Probably more companies too. You might want to think about a CID intake. There is no better intake if you have the room. We have a Dart Ls Next 427 and its 12:1 compression. Pro Systems built us a 1100 Dominator for it. We had a Senior on it with a ultra 950. Just by bolting those 2 items on our motor and doing nothing else it dynode 49 more HP and another 67 foot pounds of torque. Everyone there was totally shocked. We could never get the plugs to look the sane with the other setup. But on this setup they all look the same. All the characteristics of the way it runs is completely different. Way better. At 50 degrees you can fire it up and immediately put it in gear and it will sit there and idle. It never would do that before. We used to have to wait till it got 150 degrees before it would idle in gear. On the car, we did have to go to a way bigger stall to get it out of the hole. After we did that Wow does it come out now and goes thru the whole run flawlessly. We are very happy all the way around. Just something to think about.

I also have been thinking about the Pro1 heads to replace the 5364 castings I have now. Sps does mine and he has a program also, many do. Camshaft design and spring choice is going to play a huge part in keeping a HR happy at rpm, especially if not using titanium valves.I too have the CID and can verify what TTur1996 says....Near equal length runners helped a ton in getting the A/F correct. Many times the variance between short and long cyl is only .2-.3, before there could be a whole 1. off. Key is making all parts play well with others.

Alternate Heads
 

I have to agree with NAVYBLUE210. I think the AFR will not only exceed the Darts, but give more low end besides.

I agree with you guys as well. Should have suggested it also. Why you might ask. Because we run AFR heads that have had some work. These babies flow big time. We believe this is why it responded so well to the larger intake and carb. With the smaller setup you could just tell it was holding it back. Best part is that you don't have to spin it very fast to make max power with big block torque.

Thanks I did look at the AFR head but having the small port volume I didn't think it had enough to run up to 8000. Ill be rethinking my choices again. I talked to Borowski and they are over the budget on the dart heads set up with light valves.

Long story short, AFR makes a 260cc port do more at most lift levels than many 280cc ports.
What NAVYBLUE210 says above makes a lot of sense.

Imo AFR heads are under rated. You hardly hear anything about them. But there are many making big power with them at a fraction of the cost of others. Hell their 245cc cathedrals flow 360 in. and 267ex. @ .650 lift. Not many can claim that.

I can tell you one thing. With Borowski you are getting what you are paying for. They will treat you like a person not an object with money. Ken and his staff are very professional and take great pride in what they do. Since Ken bought the place he has retooled it with state of the art equipment. Some that no one else has yet. Really can't say enough good things about them. If you have them build you a motor you won't even be surprised if you see Ken or one of his staff show up at the track to see how everything is going. Great People for sure.

My issue would be if the builder is a Dart Dealer, and pushing Dart Heads even when the AFR or TFS LS3 Heads would be a
BETTER & less expensive choice for the OPs build goals and application.

They sell Dart, All Pro, AFR, Brodix,and a few others. They will not push anything on anyone. If you ask them they will make suggestions based on what performance level your looking for but would never push anything on anyone. In fact they have no problem building what ever you have with your own parts too. So that's not the case what so ever. I'm sure the OP called and asked about a particular head not having anything pushed on him. Very personable people. If anyone has a chance to deal with them you will see what I mean.

So I located and purchased a RYR nascar spec engine dressed for $5200. This is a ls2 engine that is 620hp and 500tq.Wegner did the assembly according to the markings on the engine.

Any idea on cam specs for a NASCAR LS spec motor ?

https://cimg9.ibsrv.net/gimg/ls1tech...704226545.jpeg
https://cimg0.ibsrv.net/gimg/ls1tech...cb63ae2ac.jpeg

Interesting.... thanks.

Thanks for posting specs. Another reason to have everything working together making power.

What compression and what inake manifold is on that engine?

The intake is a super victor and the compression is from what ive read is 10.8 to 1.

So its basically a stock longblock ls2 with an under .600 lift cam and a super vic and makes 600 hp and 500 lb ft?

Is that what i'm reading?

makes over 600 hp

Hard to believe that motor makes that power with those specs. Nascar boys did wonders on those heads to say the least.

Exactly my thoughts.

Wegner says that they make 620-625 hp and 510 tq on the ls2. They make 680 with the ls3 head on a 6.2 @ 11 to 1. These engines are nothing exotic just the right combination.

https://cimg7.ibsrv.net/gimg/ls1tech...4bc75c35a.jpeg
https://cimg8.ibsrv.net/gimg/ls1tech...98ece76dc.jpeg
https://cimg9.ibsrv.net/gimg/ls1tech...b94ff78da.jpeg
https://cimg0.ibsrv.net/gimg/ls1tech...0a55758bf.jpeg
https://cimg1.ibsrv.net/gimg/ls1tech...a63539a29.jpeg