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RE: 32-valve modular 4.6L valve angles. By Bill Conley - 03/20/2002 9:09:02 PM; IP 67.227.45.250 Unfortunately Dave, the 4-valve head got the short end of the stick when it came to valve included angle. Part of the "modular engine" concept was that the 2-valve and 4-valve heads had to run down the same machining line at Romeo Engine Plant. This means valve angle relative to head deck had to be the same for both types. The 2-valve was planned to outsell the 4-valve by at least 10:1 so the angle was optimized for the 2-valve. Unfortunately a 2-valve wedge chamber and a 4-valve pentroof chamber are two very different animals. This limits the performance potential of the Cobra engine. Here's an even more significant limitation designed into these engines. The block was designed to be very short (for FWD transverse installations). The main and rod bearing widths were reduced accordingly. Through lots of analysis and testing, they got a minimal bearing width that would work at 100 HP/liter. That means 460 HP and no more. (Note that the stroked 5.4 blocks have the same bottom end as the 4.6 blocks.) I would be extremely surprised if they tried to release the new GT-40 with that 500 HP supercharged engine. It won't live if pushed hard. Oh- regarding the 2.3L question. No the old 2.3L and the 4.6L don't share the same piston. There was originally a new 2.3L four cylinder planned for the modular family. 2.3L was chosen because it was considered the biggest displacement for a 4-cylinder before you needed balance shafts. It also happened to make a respectable V8 displacement when multiplied by two. There was also supposed to be 3.5L 90 degree V6- but that's another story... A funny story that ties into the 2.3L. Just before the launch of the 4-valve modular (Lincoln MK VII), Saddam Hussein invaded Kuwait and threatened the world oil supply. The next day Hank Lenox, our chief engine engineer was in the drafting room screaming. "What the hell am I going to do with 100,000 4-valve V8 cylinder heads?" He and a few guys burned the midnight oil to lay out a new project. You guessed it- Graft the 4.6L 4-valve head to the existing 2.3L iron block. Yuck!! As it turned out the existing block had almost exactly the right bore diameter and spacing. Fortunately the situation calmed down and the project was abandoned. Good thing for you Cobra guys! Man you all are taking me back to some pretty wild days! -Bill

This thread, so far...

Skip Navigation Links.  A 428 fits surpringly well in this '57 (?) T-Bird... -- Mr F, 03/18/2002  I found one in a '60 t-bird. -- Greg, 03/18/2002  For years a picture in Ford's Engine Toolroom... -- Bill Conley, 03/19/2002  You mean Bill Coon's famous race car? N/M -- kevin, 03/19/2002  Yeah I think you're right -- Bill Conley, 03/19/2002  How long were you at Ford? Any stories? :-) [n/m] -- Mr F, 03/19/2002  RE: How long were you at Ford? Any stories? :-) [n/m] -- Bill Conley, 03/19/2002  Stories !! -- P, 03/19/2002  Ok- Twist my arm! -- Bill Conley, 03/20/2002  RE: Ok- Twist my arm! -- Bob, 03/20/2002  32-valve modular 4.6L valve angles. -- Dave Shoe, 03/20/2002 RE: 32-valve modular 4.6L valve angles. -- Bill Conley, 03/20/2002  Wow, there's a name outta my past... -- Dan Davis, 03/20/2002  Unnatural adaptations. -- Dave Shoe, 03/20/2002  Cam Bearing Spacing -- Bill Conley, 03/20/2002  RE: Wow, there's a name outta my past... -- Bob, 03/20/2002  OK Bob - One more (not Ford) -- Bill Conley, 03/20/2002  That's a good one! Heads must have rolled... [n/m] -- Mr F, 03/21/2002  Welcome to Europe -- John, 03/21/2002  Gee, Dan - sounds like a tough gig. ::LOL:: [n/m] -- Mr F, 03/21/2002  RE: Ok- Twist my arm! -- P, 03/21/2002

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