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Does anyone have experience using this head? How will it perform on a street car? How does this head compare to any of the modern after market heads available today? They have 62 cc chambers, 2.02 x 1.60 valves, screw-in studs and guide plates, I do not know the runner sizes. The exhaust side seems to look a little small compared to some in my head collection. This might be a good question for Mike or Paul to comment on. I do not recall a post on this topic. Bill
I think those are the ones I used to run several years ago, but mine were ported and had 2.08 valves. I ran 10.80's with them on a high compression 406 with a huge roller cam. A friend owns them now and he runs 10.50's in a Vega.
Here's GM's description:
10134392 Phase 2 Cast Iron Bow Tie Head
The Phase 2 Bow Tie cylinder head (casting P/N 14011034) has the highest performance potential of any cast iron Chevrolet head. It is intended for off-highway applications only. Although the Phase 2 cast iron Bow Tie cylinder head has the same casting number (14011034) as the Phase 1 head it replaced, there are several significant differences between these two heavy-duty cylinder heads. The Phase 2 cast iron Bow Tie head can be identified by its redesigned outer water jacket wall with a machined bar between the exhaust manifold flanges. (Phase 1 castings have a raised parting line between the exhaust manifold flanges.) The area around the tapped water temperature sensor hole is also machined flat on the Phase 2 head. The Phase 2 Bow Tie head has a revised combustion chamber design with a true volume of 64cc's. The quench areas beneath the spark plugs are filled to increase compression in competition engines. The intake valve seats are machined for 2.02" diameter valves; the induction hardened exhaust valve seats are finished for 1.60" diameter valves. The intake and exhaust ports are identical in Phase 1 and Phase 2 cast iron Bow Tie heads. The 184cc intake runners will satisfy the airflow requirements of most competition engines while enhancing throttle response and mid-range torque. In unmodified form, the Phase 2 Bow Tie head will flow more air than any production cast iron small-block head. Extra-thick wall sections allow the ports to be enlarged to increase their flow capacity. The manifold heat riser passages are deleted in Phase 2 Bow Tie heads to produce a cool, dense intake charge.
Technical Notes: The valve spring pockets in cast iron Bow Tie heads are machined for up to 1.50" diameter competition valve springs. The rocker stud bosses are tapped for screw-in studs; studs and pushrod guideplates are not included. Use GM Performance Parts studs P/N 3973416 (3/8") or P/N 3921912 (7/16") and hardened pushrod guideplates P/N 3973418. Use 5/8" hex-head spark plugs with tapered seats and 3/8" reach. A bare casting weighs approximately 42 pounds. Valve seats are heat-treated.
69 Nova 410" small block-Driven to track
6.39 E.T./105 MPH--6.11/112.89 w/N2O bowtie0069.fotki.com/
If you have that part number then yes it is a phase 2 head.
It was designed and made for Racing, mostly Stock car racing.
If you go back to the original 292 angle head
this head was based off that head, and changes were made to make it stronger for the larger valve springs, and better valve seats.
It is considered one of the most durable heads for a small block Nascar Local series racing.
The head was used in the Circle Track Crate engine program 350ci sealed engines with cast iron heads before they changed to the Vortec heads.
In circle track racing were you built your own engine instead of purchasing a sealed engine and most track rules dictated you use that head. They pushed for change to the aluminum head, mostly because of ease of repair from major damage. You can weld up a aluminum head, very hard on a cast head.
Maybe someone who has done some circle track racing can remember the older cast iron head sealed engine. If I remember it was a 350/300 hp engine and had a flat tappet cam.
Now replaced by 88958602 CT350
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