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243 head question... larger valves or more compression

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Old 04-27-2017, 03:11 PM
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More than just those 2 things effect velocity.
Alot more.
Most of the time everyone gets caught up in the numbers.
Well those will change drastically based off what intake you use on it. So how can you know what itll be?
Old 04-27-2017, 03:39 PM
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I got some flow numbers form Lingenfelter, and their stock valve heads flow a lot at .200 - .400, and on par with TEA at .500. But the intake runner is 246cc.
Old 04-27-2017, 03:43 PM
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Port flow is not port velocity. 246cc is a very large runner. not meant for a smaller cid street app imo. 205 to 230 is max on a street driven ls1.
Old 04-27-2017, 04:03 PM
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Originally Posted by tech@WS6store
Port flow is not port velocity. 246cc is a very large runner. not meant for a smaller cid street app imo. 205 to 230 is max on a street driven ls1.
That's what I thought.
Old 04-27-2017, 04:44 PM
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Originally Posted by JakeFusion
TEA CNC'd the chambers on mine, creating a new chamber shape and quench area. The softening does the same thing - to change how the flame front travels and to alter the quench area/shape. TEA does it with the CNC - but for like another $100 or so they will go back and hand finish and create a mirror polish on the chamber which takes it to another level.
Would the mirror polish be a benefit to an NA car?
Old 04-27-2017, 07:08 PM
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It doesn't hurt. It would fight detonation better. Talk to Greg @ TEA or Brian Tooley.
Old 04-28-2017, 11:05 AM
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Originally Posted by JakeFusion
It doesn't hurt. It would fight detonation better. Talk to Greg @ TEA or Brian Tooley.
I'll see what Greg says, since I've already been talking to him about the heads.
Old 04-28-2017, 01:25 PM
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So, I decided to look at all of the flow numbers as if everything had a 230cc intake runner and a 4" bore. Now it makes more sense. Aftermarket > ported 243/799. Since I can get stage 1 now, and upgrade to stage 2 when I get a sleeved shortbolock down the road... TEA is still the best choice for me.



Last edited by FCar2000TA; 04-28-2017 at 03:44 PM.
Old 04-28-2017, 01:50 PM
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Unless you have every head flowed at that with that cc port and that bore, you cannot adjust numbers based off % difference from their size to a 230cc and the flowed bore to a 4inch. You cannot manipulate numbers like that. They will not be true.
Old 04-28-2017, 02:45 PM
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Originally Posted by tech@WS6store
Unless you have every head flowed at that with that cc port and that bore, you cannot adjust numbers based off % difference from their size to a 230cc and the flowed bore to a 4inch. You cannot manipulate numbers like that. They will not be true.
I know that the numbers are not true, but I thought it would at least allow me to see which heads are likely to have better velocity than others. The list is pretty much in line with what I have read on here, and elsewhere. The only monkeywrench is that two that I have read good things about are at the bottom, but I don't think that those heads should be at the bottom.

Last edited by FCar2000TA; 04-28-2017 at 03:42 PM.
Old 04-28-2017, 02:52 PM
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Saw these on Craigslist and figured they might help with the flow numbers

In all seriousness though taking the AI 226 and 232 and correcting them to 230 doesn't make sense. If you have a formula to correct all the values to a 3.9" bore at the same pressure than that info would be useful. Assuming you are going to put the same intake infront of any of the heads then that would remain a constant. The only way to directly compare the numbers is if all are tested exactly the same.
Old 04-28-2017, 03:02 PM
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Jake is giving good advice
Do both if you can

Theres no perfect pick out there cant race a flowbench or dyno
Old 04-28-2017, 03:48 PM
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I was just trying to make sense of all of the numbers. In anycase, I have probably made up my mind.



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