Dynamometer Results & Comparisons - C5 Z06 Pat G/EPS 226/230 cam only, makes 450/434??????????

Been going to this shop for years. The dyno is always accurate. Pat G spec'd a cam for my buddies bolt on C5Z and we just got it tuned last night. Final numbers were 450/434 with 24* total and 12.4-5 across. Car is stock besides some old school breathless perf. Vortech rammer intake and Bellenger tri Y headers and no cats. Cam is a eps/LXL 226/230 on a 111 I believe.
STOCK 243's!! Car has 50k miles on it...
450/434?! C'mon.....


Pre cam his car did 389/380....

My CTS-V did 419/396 with the same cam on a 113+2

My current Z06 did 389/381 with long tubes, X, vararam and a tune. Identical to what his did.

I'm so lost right now! I compared all correction factors and they're all .010 within each other. This is a dyno dynamics dyno as well.

Anyone have any thoughts??

A definite dyno error. A stock bottom 346ci engine with stock unported heads will not make 434tq. Especially through a Corvette drivetrain.

I think it's right on par, dunno why you think those are low numbers. On a non-corvette drivetrain, that's probably more like 430ish at the rear wheels. That's a good number for a medium cam on stock 243s and 346 cubes.

If you had a cam in the mid 230s and ported heads then yeah I'd expect more, but for a medium cam and stock heads those are good numbers.

How much do you expect to gain out of a 226/230 cam? It already went from 389 to 450, thats 61rwhp from the cam alone. I'd say that's a damn good bump in power from just a cam swap.

Are you complaining about it being too low? Thats damn good for a cam-only LS6!

I'm saying that's high. Don't know how you could take my post otherwise. Lol

Yeah i thought you meant low. I was like uuhhhh WTF?

I think it's right on par, dunno why you think those are low numbers. On a non-corvette drivetrain, that's probably more like 430ish at the rear wheels.

I'm not sure what you're getting at here, but you do know that Corvette's dyno less than most solid axle cars right?

If my gto dynos anywhere near that i will literally shit a brick. I got the bigger eps cam.

Its clearly a dyno error. These are max effort cam/ AFR, TFS headed #'s...

I was thinking it'd do roughly 430/400...

Yea you made the same power and more torque then my c5z06 don't think so. I had a little more cam ported tfs 220's milled to 59cc and a ported fast 92/92 and I went 450/412. Deff some dyno error here. I would expect around 415/395 would be more realistic.

I think it's right on par, dunno why you think those are low numbers. On a non-corvette drivetrain, that's probably more like 430ish at the rear wheels. That's a good number for a medium cam on stock 243s and 346 cubes.

If you had a cam in the mid 230s and ported heads then yeah I'd expect more, but for a medium cam and stock heads those are good numbers.

How much do you expect to gain out of a 226/230 cam? It already went from 389 to 450, thats 61rwhp from the cam alone. I'd say that's a damn good bump in power from just a cam swap.


Is this a joke? Lol

Did it make those numbers on one pull or multiple pulls? The HP is high, but more believable than the TQ, but since the TQ is incorrectly high, the HP would follow.

Did it make those numbers on one pull or multiple pulls? The HP is high, but more believable than the TQ, but since the TQ is incorrectly high, the HP would follow.

Multiple pulls. As he tuned it got higher. They go hand in hand so yes.. One would follow the other. The HP is high but who knows it could be a freak, but the tq? Absolutely not....

While the gains seem a little high on paper, how does it feel on the street? Does it feel like 60 rwhp or more like 30? For what it's worth, that's a really good size LS6 cam for offering power gains with good street manners. Still, gaining 61 rwhp over an LS6 cam is a bit much. The trap speed at the track will tell the real story.

Still breaking in the clutch... Trying to not go WOT on if for at least 3-400 miles. On the last pull of the night with the cut outs open for grins the clutch started to slip. The new LS7 only has 100 miles on it.

That's what I thought, what should it be trapping at that power level? Take dyno #'s with a grain of salt and the real test is the track, you just can't get that thru to some people tho... But is there anything wrong with wanting some consistency with these damn machines?! Lol

We shall see...

He can test it out against me. And a 450/434 c5z at sac raceway should trap 124-126

The dyno was happy thats for sure

I'm not sure what you're getting at here, but you do know that Corvette's dyno less than most solid axle cars right?

Why is that? Because I seriously thought vetts Dyno higher.

Why is that? Because I seriously thought vetts Dyno higher.

TQ tube, rear mounted trans, IRS, half shafts, etc.

Irs would be the reason

Oh ok. Thanks :thumb:

Look at uncorrected vs corrected. Look at ambient temp, humidity, and baro pressure. Or look at correction factor, whichever you can get.

I had a cam only 04 Z06 with all bolt-ons and a lil smaller cam that put down 442RWHP and 407RWTQ your hp seems right but TQ is high my highest trap was 128mph to give a comparison

I'm saying that's high. Don't know how you could take my post otherwise. Lol

I think it was BC you put only makes in the title. I thought you meant they were low too at first ...

It was 1.141 .041 or .410

I don't remember lol

Which one make more sense at sea level about 60-65*

I think it was BC you put only makes in the title. I thought you meant they were low too at first ...

Yep, It took me a while too figuring out he meant; EPS cam only, makes

It was 1.141 .041 or .410

I don't remember lol

Which one make more sense at sea level about 60-65*

Find out.......it will most likely give you your answer. Unless your just posting for something to talk about and really arent concerned with whats happening?

If it is 1.14 on the correction factor, its adding 14% to the uncorrected results, which is telling. Assuming your at or near sea level with 65ish temps your correction factor should be much closer to 1.00 STP/STD or. 96 for SAE, which would take your uncorected power and take away some power when corrected.

SAE or STP/STD corrected?

Absolutely I want to get to the bottom of it. Because now I look stupid, swearing up and down and side to side that it's absolutely absurd to even think that a stock headed 346 motor with full exhaust and a 226/230 cam is legitimately making 450hp/434tq. It's driving me insane!


Ok. I'm calm..... Lol

It is too high...if it was a max effort cam, I could maybe believe it, but not from a 226/230 cam only.

The correction factor was 1.114 and when I had my car on the same dyno, mine was 1.110.... This is crazy talk!!

EPS 226/230 111lsa. If you want insane cam only power, get this one....??? Lol

Better question is... Why was my CTS-V with the same cam but on a 113+2 with same mods doing 419/396, on the same dyno.

Hmmm...

I don't know why you keep saying that your 226/230 113 +2 cam is the same as Steve's 226/230 111 +2 cam. They are more different than you're giving credit.

The 111LSA cam has 6 degrees of overlap, the 113LSA cam has 2 degrees. With a good scavenging exhaust, 4 degrees of overlap is worth some power. Steve's DCR was 8.27:1 with the 111 +2 cam, yours was 8.14:1. That extra DCR pumps up mid-range torque. More torque. Steve's 111 +2 cam also uses the newer LXL lobes for the exhaust. Not sure if the quieter, softer closing, higher lift lobe is helping make more power, but it is another change from your EPS/EPS lobed cam.

Not sure if your CTS-V still has the heavy stock flywheel, but those really pull down dyno numbers on those that still run them. Vettes are know for putting down better numbers than CTS-Vs. The cold air intakes and exhaust routing is typically better than the Cadillacs. Small differences of course, but it's not exactly an apples to apples comparison.

Ask the dyno owner what the inertial weight he had entered for the driveline weight. Also if the temp was 65* and humidity was decent with a decent baro the air density correction should have been closer to 0.95x. The 1.14 correction you are talking about is probably the "extra correction" that alot of dyno dynamics owners use to get equivalent to dynojet numbers. On my dyno dynamics we have that set at 1.13 with testing from ours to a dynojet so it reads the same. Without that extra correction calibrated these dynos read STUPID low numbers. My cam only ls1 only managed 350rwhp with the extra correction set to 1.00x

Sorry pat. I forget all the numbers. Just crazy to think all these small things add up to so much. With all this being said, if he were to switch to a EPS/LXL 230/234 113+3 what would the numbers look like, roughly?

if he were to switch to a EPS/LXL 230/234 113+3 what would the numbers look like, roughly?

I called Geoff and he ground me a EPS/LXL 230/238 113+2 to go with my lightly worked 799 heads (shaved .010")

Don't have dyno numbers but it gained significantly from idle to redline (which I moved up to 6600rpm and it feels like it's still pulling) over my old 230/224 XE lobed cam.

I was most surprised by the bump in low end where I was more worried about losing power. I hope to get new track numbers Sunday, but on the street there is almost no comparison.

Nice ^^