Here's a flow chart from the last GM 906 I ported.....the flow numbers A Guide to Vortec vs OE Small Block Chevy Heads ... numbers chart. Enter the Vortec Heads. ... to flow better. Iron Vortec Head All the Details ... Look for casting number ... and exhaust ports in a standard-water-flow iron head. Super Chevy tech article on Vortec cylinder heads. ... GM Performance's New Vortec Heads Promise Big Flow Numbers For A ... More than flow bench numbers The good vs bad chevy vortec heads. ... and about the only differences are most of the 906 heads have hardened seat inserts ... published flow numbers Vortec 906 Heads HoneyBadger OBS. Loading ... Vortec Cylinder Heads - Summit Racing Quick Flicks - Duration: 5:33. Summit Racing 107,428 views. 5:33. Find great deals on eBay for 906 Vortec Heads in Cylinder Heads ... Professionally rebuilt pair of small block Chevrolet VORTEC cylinder heads. Casting number is: 906. The only difference between the #062 and #906 Vortec head is in the ... GM Vortec Heads are casting number '060' but ... vortec heads. Your vortec heads are from GM and for 3/4 and 1 ton truck. You have a single ground valve with the harden set installed. GM did this to keep the exhaust valve cooler under heavy load, and pulling that load for a long time. Vortec heads like to crack on the exhaust valve down the runner with out over heating. Personally, I believe that vortec heads are the best choice for a primarily street driven car. Their low and midlift numbers combined with small high velocity ports produce incredible torque down in the street use(1000-5000) rpm range. Im a sumwhat newbie too and i dont know if those flow numbers are good or average but my engine damn sure move and scream. ... Porting 906 Vortec Heads. flow chart for stock unported vortec SBC heads? Drivetrain & Performance Now, that my rant about flow numbers is over I'll get back to something that may be helpful. Here are some good articles to take a look at, not all of them may deal with OE vortec heads but they at least outline some good aftermarket Chevy heads to use for budget performance builds. Please take your time in looking through all of these. Displacement, mostly. The large-port heads could use a larger-cube engine to make the most of their capability. Regardless, the new iron heads showed that they had the flow to keep up with--and surpass--aluminum heads. The test session didn't compare aftermarket heads with the new Vortec Bow-Ties, nor were the iron heads ported or machined in The L31 Vortec comes in two different casting numbers, 10239906 (#906) ... -vortec-heads MACHINING VORTEC HEADS, and OTHER HEADS. Discussion in 'Cams, Heads and Valve Trains' started by grumpyvette, Oct 7, 2008. flow chart for stock unported vortec SBC heads? Drivetrain & Performance Chevy Numbers Decoding; Search. The 906 Vortec came in two "versions" as Soonerjay mentioned. ... all the L-31 Vortec heads are the same and flow I've toyed with Vortec's for a LONG time but their purchase, upgrading to a stainless valve package, adequate valve springs and refreshing a set of used heads makes these a logical option. The Patriot "vortec" 185's outflow Vortec's on EVERY level and still retain the Vortec's chamber and awesome port velocity you want on the street. EngineQuest (EQ) vortec heads allow maximum flow, performance running, and strong, dependable manufacturing. Post: Vortec 906 Heads (Topic#243241) 427_4speed Senior Member Posts: 264 ... send me your emaill addy and i will scan you the flow numbers i Are all those heads basicaly the same flow wise? does anyone know flow numbers? Are some vortec heads more desirable ... #906 Car Craft magazine's technical article on porting GM Iron Vortec cylinder heads. Chevy Numbers Decoding; Search. The 906 Vortec came in two "versions" as Soonerjay mentioned. ... all the L-31 Vortec heads are the same and flow 062 vs 906 Vortec Heads ... - and 1-ton trucks came with Vortec heads equipped with a specially hardened exhaust seat that kills low- and mid-lift flow. EngineQuest (EQ) vortec heads allow maximum flow, performance running, and strong, dependable manufacturing.