CFM Flow numbers for stock heads on an 09 Sierra 5.3???
 

Anybody know these? Trying to get the stock engine specs on my desktop dyno, so I can run cam swap data before I purchase... gotta have the flow numbers first.

I would say 799 heads flow I260 E210 @.600...But I could be way off

ok, thats a good start. Thanks.

I should have been more specific. I need the flow numbers for .100 lift, .200, .300, .400, etc. All the way through total lift at the valve, for both intake and exhaust.

I'm still searching for the stock flow chart, but if someone can beat me to it, I'd really appreciate it.

And, what are the stock valve sizes?

Casting Number 243
Head: 2001 LS6 5.7 Liter Passenger Car
Material: Aluminum
Part Number:
12564243
Combustion Chamber Volume: 64.45cc
Compression Ratio: 10.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Stock Head Flow Numbers
Chamber 64.45 cc-------0.100---0.200--0.300--0.400---0.500---0.550---0.600
Intake 210 cc------------62------126----184----224-----251----256----257
Exhaust 75 cc------------57------108----143----163-----176----180----183

That is for a 243 head. A 799 head should be very similar in flow numbers. Both castings have the same size valves.

thank you very much. If i can ever find the 799 flow numbers I'll be sure to post them.

Well... After finally deciding to pull my head out of my a$$ and verify what heads are actually on my truck I have discovered that I have a set of 243 LS6 heads. So, with that new found information, I would have to say the numbers I have received are spot on. Thanks again for all the help.

spec's
 

I would like the info on the 799 heads,if any has them.

Here is some good info that says they are about the same as the 243's......

"This appears to be one of the common misconceptions about heads having the 243 casting no. -- they are not necessarily LS6 head assemblies. The LS2 heads (243 or 799 casting) have the "heavy" standard LS1 valves. However, they do have the LS6 springs.

"Only the true LS6 engine heads have stainless steel (not titanium) hollow stem valves (the exhaust stems are sodium filled). These valves are slightly longer than LS1 valves too.

"The LS7 heads do have titanium valves.

"New LS2 heads are about half the price of new LS6 heads (check sdparts.com). GM is "really proud" of those hollow stem valves!

"Oh, if you have the 799 castings -- the only thing "Corvette" about them is the valve springs/retainers! Still a desirable set of LS1 heads though!

"Supposedly, the 243 mold was done at GM Research, the 799 mold furnished to other vendors. The same vendor may have the 243 and 799 mold.

"Both heads have identical sized intake and exhaust valves."

their the same head, different casting #.....

243-799
 

I was told the valves sizes and cc's were diff. :confused: