Mopar B Block Cylinder Head Recommendations

[Ian Northeast]

Hello everyone,
The work on this years Bonneville car has been progressing really well.
We have been getting some really good numbers from the dyno room but as things increase the weaker parts are beginning to show themselves.
It's looking a lot like we may need to change our cylinder heads, at this late stage we can't change either inlet or exhaust manifold setups which use the standard fittings. Alas hemi is out of the question.
There appears to be a bewildering array of cylinder heads available and I would welcome any recommendations from more experienced people.
We are running a single turbo and are expecting figures in the region of 850 bhp.
Any suggestions gratefully accepted

Ian

[Sandmann120]

Sorry to dredge this one up, but are you needing to stay iron, or looking for aluminum?

[Ian Northeast]

Absolutely no need to stay with Iron, I'm already using 440 source aluminium heads.

Ian

[Crackerman]

Do you have motortrend tv? On one episode of engine masters, freiburger and the guys did a Mopar head test.

If I remember correctly, out of the box Edelbrock heads did really well, with room for improvement.

[panic]

I've yet to see any test that heads that flow well NA will have the same result in turbo.
The head on my 320 hp 3.0 liter 2JZ-GTE engine is almost identical as to port flow rates, intake:exhaust bias, chamber shape, etc. to the base NA 225 hp engine. Why does it work so well boosted? Don't ask Toyota, it was an accident.

As an aside, IMHO the "ideal" head for boost is not common to both turbo and mechanical supercharger.

[1leg]

What are you breaking on the 440source heads?

[Crackerman]

I've yet to see any test that heads that flow well NA will have the same result in turbo.
The head on my 320 hp 3.0 liter 2JZ-GTE engine is almost identical as to port flow rates, intake:exhaust bias, chamber shape, etc. to the base NA 225 hp engine. Why does it work so well boosted? Don't ask Toyota, it was an accident.

As an aside, IMHO the "ideal" head for boost is not common to both turbo and mechanical supercharger.

While I do agree with this statement whole heartedly, the machinery required to flow a head at positive pressure is INSANE!  Massive 3 phase motor, 100hp quite possibly, driving a vortech supercharger of sorts.. just to get the airflow.

So, a "good" flowing head, n/a on a superflow type bench, is a good indication of performance and flow under boost.

For instance, the Cummins diesel 12v head... 130-140 cfm, with some serious port wok can go upwards of 180-190 (in the factory casting)... But throw 80psi of boost on it, and suddenly it makes some power.
Aftermarket heads flow 260to 280ish, but make the same power at much less boost, and much lower drive pressures.

These are all apples to oranges to a Mopar head. But what I am saying is, if it makes more power n/a, it's gonna make more power boosted.