LS3 Cam and valvetrain upgrade

[shane_3800]

its all LS tho stock intake and TB, and i could prob do more with the port flow per lift as i just quickly went thru and made it sorta linier, if its all added in right then it works, but there is alot of data to get right

Yea that is your problem.
The port is anything but linear, it's got a taper up to the bowl, then the bowl opens up and slows the air speed down and then the valve seat is meant to act like a venturi.
Look at that series of Darrin Morgan video I posted, he goes into air flow and wet flow.
Darrin is the guru.

 

[shane_3800]

Nathan Higgins had darrin design the holden heads for him, the only reason he uses Gale Pauli now is that Darrin is working for BES and can't be contracted out.

 

[shane_3800]

Head porting isn't rocket surgery.
I haven't had a go for years now, I still have all the burrs in my tool box.
But I understand the math more these days.

You just want to hit the MCSA then after that you need to slow the air down at the points where you want it to IE; where it's too fast.
where it's fast open that area up to make volume to slow it down, then have a radius to slow it down on the short turn, it's quite easy, most people look at TK photos and think it's black magic.

 

[shane_3800]

The throat, you don't want to go past 93%, keeping at 91% is a good safe place, then you want a venturi, well guess what the CNC valve machines can do that so these days you don't even need to hand port the under seat into bowl cut as the single point cutter machines can do it.

 

[shane_3800]

07GTS, you're no fun, I love debating this stuff, and you disappear. I could talk valve and cam mathematics all night.

 

[lmoengnr]

In rifle world there is a body called SAMI, they test rifle pressures by adding a probe into the chamber, it's a little hole drilled into the barrel that lets the chamber pressure be measured, that is how we know most rifles operate between 50 and 60,000psi.
Just FIY.

SAAMI haven't used 'copper crushers' for measuring chamber pressures since the early 80's. They now use pressure transducers so they can measure peak pressures, and trailing pressures. Even the old school 'Proof Houses' in England have gone electronic.
Most of the new 'short magnums' operate above 65,000 PSI, and the .277 Sig Fury with a hybrid brass/steel case should operate at about 90,000 PSI.

 

[shane_3800]

SAAMI haven't used 'copper crushers' for measuring chamber pressures since the early 80's. They now use pressure transducers so they can measure peak pressures, and trailing pressures. Even the old school 'Proof Houses' in England have gone electronic.
Most of the new 'short magnums' operate above 65,000 PSI, and the .277 Sig Fury with a hybrid brass/steel case should operate at about 90,000 PSI.

Yea agree, but they still have to drill a hole into the chamber.

 

[Fu Manchu]

07GTS, you're no fun, I love debating this stuff, and you disappear. I could talk valve and cam mathematics all night.

Dude. You are debating yourself with two pages of you post g to yourself. @OP has long gone.

 

[lmoengnr]

Yea agree, but they still have to drill a hole into the chamber.

No they don't... No longer required.

 

[losh1971]

Dude. You are debating yourself with two pages of you post g to yourself. @OP has long gone.

No he hasn't....