Katech CNC
#49
Radius was used on the intake side. Number two is exhaust w/o pipe and 3 is with a 1.75" bend. Approximately 10" long like a 90 degree
Basically my old DIY 241s flowed identical on the exhaust side on a 15K GM valve job and new ZO6 hollows. I will admit that my runner volume was larger than this Katech one. So less efficient
On the intake side, I ground out the rocker bump and bowl blended the 241s this same way and they flowed 246 @.600". So these Katech runners are a full 25 CFM up at that same lift point.
Surprised I guess that these continued to flow more CFM on both IN/EX @.650" and .700" lift points. Useless with most HYD setups Wonder if that's again, this poopy *** GM valve job. Once these are outfitted with the Lunati dual spring kit I will have exactly one grand invested into them which was my self imposed budget if you will
Last edited by A.R. Shale Targa; 10-20-2017 at 05:10 PM. Reason: spelling
#53
Flowed on a FOUR INCH BORE
go ahead and compare all the lift points of my 500 dollar CNC'd crap castings to
The single finest GM cathedral flowed on a FOUR INCH BORE
I really love the stall going on beyond the .500" lift point which you choose to use since nobody cams their engines by opening the valves more than that
#56
TECH Veteran
iTrader: (2)
Flowed on a FOUR INCH BORE
go ahead and compare all the lift points of my 500 dollar CNC'd crap castings to
The single finest GM cathedral flowed on a FOUR INCH BORE
I really love the stall going on beyond the .500" lift point which you choose to use since nobody cams their engines by opening the valves more than that
Last edited by wannafbody; 10-20-2017 at 11:28 PM.
#57
I needed to flow mine for the purpose of this thread and my surface job was a bit more than the usual clean up cut that shops do for like sixty bucks. Getting .030" taken off tends to run me about $80 since so many tooling passes
The 243/799 heads are the gold standard of GM cathedral however if someone happens to already have these 853/241 heads, they have budget options available to up the power potential
And to answer your other question; yes these were flow tested on a 3.9" bore fixture
Last edited by A.R. Shale Targa; 10-23-2017 at 11:58 AM.
#58
TECH Senior Member
iTrader: (16)
For a DIY, This is not a bad option if you already had the 241, 853 heads.
It goes to show you don't need to buy a used $400 set of heads that still need a valve job, clean up, and springs. You would still be in the same price point with the 243's by the time you had all that work done and not have the same flow.
It goes to show you don't need to buy a used $400 set of heads that still need a valve job, clean up, and springs. You would still be in the same price point with the 243's by the time you had all that work done and not have the same flow.