DAMN! 408 dyno.

[CuNfUzEd]

Don't feel bad I got 380 hp 355 torque on a 408. It has 317 heads with a little work, headers, 224 cam, 20 inch tires, 4l60 trans, 4:10 gears, approx 10.5 compression. I should have went with a smaller tire on the dyno but oh well. I am like you the numbers on the dynojet are what they are. Just going to work on track times and not worry about it. Like one of the others said you don't run with a dyno under it. The way I see some people chase numbers on a dyno and some want numbers on the track. My tuner said he make the dyno show any number I want but that is not what matters.

Yeah that smarts!LOL I'd be a little down too. What is your weight and what times do you knock down?

[GA95DCMSS]

Yeah the formula I am using is 10.8.1
Engine Compression Ratio (CR) Calculator

Aren't stock 243's 65cc chamers? It's been so long sine I have used anything stock.

Bore 4
stroke 4
Gasket 4.03
thickness .040
chamber 65
dish -10

Excuse my last post. I misplaced a 0. It should have been .040 instead of .40 for gasket thickness.

The Stock 5.3 heads aren't 243's. 243s are the LS6 heads. 243s usually CC at about 64.5-65.5cc's. Stock 5.3L heads are either 852 or 706 castings. They CC at about 61cc's. If you're using a stock 5.3L top end, I'm hoping you changed valve springs at least.

Did you take into account that the Gen III motors have a negative deck height? I'm not sure about his build, but I added that into there when I recalculated it. That works out to about an 11.37-11.4:1 comp ratio; with 243's its about 11.05 (with the piston .005 above the deck) If he is using stock 5.3 heads, he is choking that engine like all hell. Even a set of 243s is going to keep that engine from working to its full potential. I understand this is a mild build, but you could have gotten 350rwhp/377rwtq out of a 6.0L with a little work, and saved yourself some cash.

Anyway, A good set of heads and an exhaust would really help alot. Throw some heads and some Pacesetters on there and have some fun lol.

[CuNfUzEd]

They are 243's for sure man. Casting numbers.....All the modern 5.3's come with them or 799's I believe. The 408 was only 3500 bucks said and done and I have a platform in which to REEEEAAALLLyy build upon. Still expected more though. As best I can tell the 4X4 is huge in the HP robbing area. Looking for headers now.LOL Those things aint cheap for the TB's though. Hell I can get 2 sets of Fbody headers for one decent set on the TB. DOH! I alos did not take into account negative deck hheight. The LQ9 block is neg huh? learn something new everyday.

[GA95DCMSS]

Ahhhh. I see. I didn't know that about the new 5.3s. I guess we both learned something lol. You can definitely build upon that. As far as I can tell, all LS based motors come from the factory with negative deck height. Stock specs are like .005-.008, but some have seen as much as .01 out of them .

[Botlfed]

uhh i was just out at the machine shop and had a set of 243s cc before milling and im pretty sure it was 67cc. arent 862s 62cc...idk it is 3:37 am