08/29/2026
Update with more numbers from testing the Brian Tooley Racing Ls3 trinity and CV CNC Ported Ls3 heads. These heads are from BTR with the port program from BTR. Just to note this is not a cylinder head shootout, this is to show real world numbers on a car with the dyno from how changing the heads and intake perform over the stock heads and stock intake. Since most guys who buy heads are usually swapping from stock heads this is to show just that, nothing else. If you're looking for a cylinder head shootout comparing all sorts of heads this is the wrong post. Hopefully soon someone will do that.
The test car
C6 Corvette
Manual transmission
Sbe ls3
Ls3 head gasket
Stock 821s with btr 660 springs
Unknown cam (it made 10hp less on baseline than another manual ls3 c6 did that had the tsp s3 na cam)
Kooks 1 7/8 headers with cats
3" Exhaust to Stock mufflers that have 2.5" inlet
Stock ls3 intake manifold
K&N air intake.
Stock 821 have a combination chamber size in the 68-69cc range. The BTR heads are 64cc out of the box so you'll have about a half point in compression bump with a stock ls3 piston. You also gain piston to valve clearance while raising the compression, that is always good on an all motor application. Stock ls3 heads with stock ls3 head gaskets has a compression ratio of 10.7:1, 64cc chamber heads with ls3 head gaskets puts the Ls3 around the 11.3:1 mark.
Dyno numbers
Stock Ls3 intake manifold stock throttle body and stock ls3 heads 469hp at 6510rpm 426lb-ft at 5383rpm
Stock ls3 heads with the BTR Ls3 trinity and the stock throttle body 494hp at 7090rpm 404lb-ft at 5733rpm
Stock ls3 heads with the BTR Ls3 trinity and the 103mm throttle body 504hp at 7002rpm 407.9lb-ft at 5611rpm
Now to the canted valve heads final numbers
BTR CV3 Heads stock ls3 intake manifold stock throttle body 523hp at 6932rpm 459lb-ft at 5483rpm
BTR CV3 Heads Ls3 Trinity with the 103mm throttle body 563hp at 7163rpm 435lb-ft at 6061rpm
BTR Heads with the BTR Trinity had a gain at peak of 94hp, at 6800rpm the gain was 101hp over the stock ls3 heads and stock ls3 intake manifold.
How the heads tune ended up being changed where it made peak hp. The 821s heads ended up making the best power with timing at 24.5* at pk hp. The CV heads made the 563hp with 22* of timing. Which is pretty common to not need as much timing in a car when the compression is raised and the head is more efficient. Both the stock heads and the CV heads didn't seem to care for any particular AFR this is fairly common on mild NA stuff.
The last pictures will be each intake manifold compared with each head.
I can't upload pictures and videos on the same post at the same time. I'll add videos either to the comments or on YouTube showing the difference throughout the RPM ranges with each head and each intake manifold.
