Hi folks

Been a long time since I've been here.

I figure if I stay away from the circus on the general board, it should be OK....

Gotta a couple questions regarding Eddy heads (the closed chamber variety.)

Rated chamber size is 63 cc. How does this compare to stock '72 - 74 360 as far as chamber volume is concerned? is there a compression gain to be had by using the Eddy's?

Also - it says in the brochures and online that adjustable rockers or pushrods must be used. Why is this? It would seem to me that if a streetable hydraulic cam is used, this should not be neccessary. Or am I missing something?

Thanks in advance.

Bruce Lozinsky

If I remember most 340-360 heads were in the 63-65ish CC range but I've CC'd them with a little more so not much if any gain there. As for requiring adjustable rockers I guess I never noticed on the LA ones. I know they are required on the Magnum ones...

unmilled 340-360 heads are somewhere around 72 cc...you should gain around one full compression point..

you can use non adjustable rocker arms and stock pushrods...

only problem is the stock rockers with the incresase spring pressure from the eddy might punch holes thru the rockers...

Stock 340/360 heads cc around 70-72cc

You should ssee about a point increase in compression.

The magnum heads needs adjustable hardware b/c it uses a cehvy style rocker not a stock mopar rocker "magnum do come 1.6 ratio on rockers from the factory"

You might get away with the stock style pushrods ands rockers on the LA versions but you need to double check this away don't just bolt on the heads a assume it is right.

just finished a few minutes ago installing rockers on eddy magnum heads...what a pain in the azz.....

Thanks everybody.

Didn't even consider the spring pressure - good point. Seems obvious now when I think of it.

It's the LA heads I'm looking at -

no..i am using a solid lifter cam, i bought an adjustable pushrod to measure the correct length..

ordered them and got them today,

problem was the rockers were not lining up with the valve tips...had to loosen the guide plates and align the tips...then retighten studs..

i guess this is my first experience with sb chevy (studs)...can not believe they just hang out in the air (cantilevered)

fun Eh!
as a recommendation to improve air flow - do some blending/rounding of the knife edge at the top of the plenum inlet.
also, check pushrod clearance thru the head, especially the intakes.