Tim 98z

iTrader: (1)

Had a Local head porter port my LS1 heads. He is known for doing DSM heads and wanted to try some LS1 heads. This is his first set ever! Heads are flown on a JKM bench for those who know about them. Manley valves 2.02 and 1.55 (or 1.56 i forget) Valve seats never changed. flown @28"
LIFT INT EX
.200 146.7 105.2
.300 207.1 143.7
.400 245.5 177.0
.450 270.3 192.9
.500 278.6 203.2
.550 282.7 210.9
.600 288.5 217.1
Remember this is a JKM bench and not the same a most of your #'s so it's hard to compare. From what i hear they would flow better on other benches. Not to mention he don't have years of practice on LS1 heads.
Then i had them milled .30 Installing with LS6 intake and Speed inc. 224/.581@112 cam <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

<small>[ March 25, 2003, 06:28 PM: Message edited by: Tim 98z ]</small>

HITMANSS

If it's hard to compare the flow numbers because the flow benches are different, then why are you trying to compare the #'s???

The intake #'s are very comparable to my Absolute Stage 1x heads, w/ stock-sized valves, w/ an LS6 intake runner attached. W/o the intake runner, the heads flowed 6-10 CFM higher.


The exhaust #'s are also similar to my heads, which were flowed w/o a 6" pipe extension. THe pipe extension typically adds about 5-6 CFM to the flow #'s.

Tim 98z

iTrader: (1)

I never said i was wanting to COMPARE them to anyone's heads. I asked what you thought and you compared them. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

J-Rod

Best thing to do would have been to do a before and after and look at the delta betweent he two to see how much he picked up those heads vs trying to compare the JKM bench to Superflow numbers.

jfm

iTrader: (4)

Bingo,what Jrod said.

CamaroSS_2002

iTrader: (4)

My flow #'s

.200 147 107
.300 199 158
.400 246 189
.500 284 217
.600 298 232

Done locally <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Slowhawk

iTrader: (12)

I agree with the above.You need before and after on the same bench to compare the gain.Also it is good to flow before and after with an intake to see what affect it had.

Richard@WCCH

iTrader: (3)

I have a JKM flow bench and your flow numbers seem to be inline with most all LS1 heads that I've tested. I must add that JKM benches typically show lower flow than the average Super Flow benches. Sometimes by as much as 15% <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Now don't think that your heads are really flowing 325+cfm either. It would help to qualify the bench by a means listed previously in this thread (before and after tests)or against another bench (second opinion). Have a professional valve job done and then test again.
Good luck,

Richard <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />