The strong probability is that the 3x2 setup would fare  no better than the single 4 on the iron heads.

I do not recall the flow on those carbs but the three carbs combined is not as good as the single 4. The heads were the cork before but with the 3x2 the cork will definitely move to the carb/intake.

I'm interested in seeing how the 3x2 does, too. And also to see how they stack up against ported iron heads.


Lawrenceville, GA

The similarity in rpm torque bands between the single four and the three deuce intake testing was indeed related to the fact that the same heads were used for both but the camshaft also plays into this as well.  Had the camshaft been a different grind but remained the same for both the 3X2 and single four tests, the peaks would have changed from the camshaft that had previously been used.  But testing with some specially tailored four barrel carbs as well as some different exhausts on the iron heads has had some dramatic effects on low end torque production so it’s still the total combination that must be considered.

 

It was interesting to note that the peak horsepower of the dyno mule engine went from 5300 rpms with the iron heads to 6100 rpms with the aluminum heads.  Same camshaft, same intake manifold, same carb spacer, same rocker ratios, same exhausts, and same carburetor.  By switching only the heads, the differences in torque production as well as the usable rpm ranges could be definitively evaluated.

 

Time constraints has put any additional 3X2 testing on the back burner for the time being.

Lorena, Texas (South of Waco)

There are a multitude of combinations which will alter the torque band.  Carburetor and/or carb spacer changes are just one way to alter these curves but there are many others.  Advancing or retarding the camshaft is another just as changing the camshaft itself can give completely different results.  And don’t forget the exhaust system.  Too many times altering one component means changing up the rest of the combination to make it optimal again.  The combinations are endless and simply comes down to how the vehicle is being driven as to what is the most desired torque band.

Lorena, Texas (South of Waco)

Ted,



Noticed that in the 3x2 testing you did a while back, the Edelbrock 573 (1. 336.0 Tq / 279.3 HP - Edelbrock ‘573’) came up with similar peak numbers as the 4bbl (G heads are 286.1 HP @ 5300 rpms and 336.4 lbft torque @ 3400 rpms) on this series of tests. Would your opinion be that the peak numbers from both of those tests are due to the restricting nature of the iron heads in both cases? I know you are quite busy, but any chance you cold run the 573 on the aluminum heads just to give us an idea what that combination is capable of?



You guys have done such an awesome job, I hope that the financial returns to you both will make this endeavor very worthwhile.

My name is Greg and I am addicted to Y's.

Is it wrong thinking to prefer the smooth and predictable curve of the new head with 4-hole spacer (the red curve) and let the tranny and drive line ratios do the work in the sweat spots?

That double-hump in the blue curve looks like it could be annoying as far as the seat of the pants signalling goes.

Cheers... Brian

Cylinder Index = 84

Current Experiment = `57 Tbird, Grand Rapids, Michigan

I called John and gave him a deposit today. Still haven't seen the latest Yblock Mag in my mailbox. With delivery of the heads by late July, it leaves me some time to clear up some other stuff. I am finishing up a home remodel in the next week or so. Then clear out the garage and install/tune the 79 Tbird disk brakes on my 65 Galaxie (daily driver). Once that is done the 312 comes out of my 57 Bird to repair a trans leak (torque converter). The motor is a solid runner with good compression which was rebuilt in Salinas some years ago. I will check the bottom end while it is out and check the cylinders. If all is good it goes back together with the Mummert heads, Sanderson's and 3 94's on a Edlebrock 573. If the short block needs freshening it will be done but I doubt it needs it. Not sure about a cam change. Leaning toward leaving well enough alone as it runs so well. But...there is a guy in my area with a sharp looking red 57 Corvette 283 that cruises by my place once in awhile. I have a history of good old Fords in my garage and driveway so the scrub guys, who get bored bumping bellies with each other, have been known to slip by here and make themselves evident. BTW, the 57 Vette runs awful, not a car guy by my estimation. Typically, here it is about money and profile, not about tool boxes and know how.



Mark

57 Black Tbird 312/auto

A minimum piston to head clearance of .035-.040" is maintaned to prevent the piston from contacting the head. Less clearance usually will mean less chance of detonation regardless of the cylinderhead material.

Piston skirt length and piston to cylinder clearance should be taken into account if you are looking to reduce this clearance below commonly accepted minimum of .035". A short piston skirt will allow the piston to rock more as will additional piston to cylinder clearance.

With regard to pricing ect. We plan to place an order for head castings around the 1st of June. The more deposits we have, the more castings we will order. Deposits of $1,000.00 received before we order castings will result in a final total price of $2049.00 (1000 + 1049) for 2 assembled heads. Orders received after we order castings will be at a higher price.

Anticipated delivery of the finished heads will be late July 2010.

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

I had no doubts the performance numbers would be good. It's the phrase… "if I can come up with the money" that's what I'm thinking. :

       A  L  A  N   F  R  A  K  E  S   ~  Tulsa, OK    

Love the phrase "get 57 supercharged power without the supercharger".If I can come up with the money to have JM build me a block,I will get me a set of aluminum heads too.

  And Don, I received my latest issue Friday the 14th.

Bud in Northern Arizona on route 66 in Winslow (standin' on the corner)

If you're American, buy American

631/2 Galaxie 500XL 406   55 T-Bird