Best Head for a Direct Mount

[Anonymous]

I'm going to the junkyard Fri. or mon. on my day off. i was going to pick up the head for a direct mount.

my question is should i get a D7 or E0, i know that they have an E0 cause i pulled my DSII setup off of a 82 Fairmont, but which sould i get if i can find a D7?

 

[pedal2themetal45]

HI
I had the same delema and this is the reply I got from Dave CZLN6

"" Of those choices, I'd be inclined to give the '65 a good lookover. If it has no cracks or flaws, that would be my first choice. The '72 would be second and the '80 last, or not at all if it is the kind with the cat attached directly to the manifold.

It is the bulges and lumps on the inside that disrupt flow. Smooth and smaller is better than larger and inconsistant.

I hope that helps. """

A 65 would be a C5 a 72 would be a D2. 80 would be E0

tim

 

[pedal2themetal45]

OOPS
For some reason I was thinking you were talking header pipes.. Anyway here a reply I got from David CZLN6 about heads

"""""After '69 the 200 and 250 heads are the same.

The after '75 heads will all have hardened seats, and a 1.75" carb hole for the larger T-bore carbs. After '77 Both 200 and 250 heads will have 1.75" intake valves and 1.5" exhaust earlier 200/250 will have 1.69" intakes.

All of these heads will have 62 cc chambers and will need to be milled to attain your compression goal. Remember to mill to compensate for the thicker Composite head gasket too.

Whatever head you do you would be wise to do a valve job, especially for economy. Be sure to specify a three angle valve job, back cut the intake valves and mill to achieve CR. Cleaning up and smoothing the chambers will help with minimizing hot spot pre-ignition for a leaner air/fuel mixture.

Be sure to check deck height and piston dish and add that into the formula for figuring CR.

For economy, you should at least go with a 9:1 CR. Higher if your elevations is above 3,500 ft.

Adios, David

"""""""""""""
Good luck
tim

 

[CZLN6]

Howdy All:

Berger- To add to the above, I'm assuming that when you say "direct mount", you are referring to direct mounting a carb to a modified log head.

If that is the case, know that the heads from '69 on came in either a hex log or a flat-top log. The flat top logs began in '69 with the 250 "M" suffix head. They appeared in several other years casting, in a variety of vehicles. We have not figured out a way to predict which vehicles they are most likely to be found on.

All EOXX heads we've see have a larger "Hex" shaped log that may be of larger internal capicity tha then log flat-top logs. They have more taps and bungs which may distort flow somewhat and the extra volume may not be helpful.

I used a D7 to modify to mount my wide base two barrle carbs to. Any can work. Either a D7 or and EO would be fine. If it is a D7BE with an "AB" suffix it will be a flat-top log!

Adios, David