Visual difference between 48 and 59 degree W2 heads?

[gzig5]

How do I tell whether a W2 head is 48 or 59 degrees just by looking at them? Can't seem to find any side by side pictures. Seems like a lot of people selling these don't have any idea what they actually have. I'm considering giving a set a try even with the expensive rocker gear but I need to find a decent set of 59 degree race heads first. I understand there are multiple chamber sizes and race vs econo rocker stands and I get all that.

 

[Sterling]

I thought all of the 48* W-2 heads were closed chamber. I would think that the push rod holes would be able to tell also.

 

[mbaird]

Pushrod holes on 48s cut int the intake face due to the angle .

 

[mbaird]

Like so

 

[gzig5]

Like so

View attachment 1716353049

Thanks. Thats the pic that I was looking for but couldn't find.

I'm not sure about the closed chamber thing. The reason I was asking about the angle is a set on FB that have what look to be open chambers and are 48 degree as seen below. But the open chambers are probably only about 65cc? I remember reading about 47cc and 55cc closed chambers. Anyway, they won't work for me but now it will be a little easier to weed through the opportunities for me.

 

[mbaird]

55cc close chamber race heads

 

[Rocket]

48 degree heads with open chamber

 

[Garrett Ellison]

Is it just me, or is there some port limitation from the pushrod holes in the 48 degree heads?

 

[Rocket]

One other difference that is not easy to see visually is the 48 degree heads have a 15 degree valve angle where the stock and most other aftermarket heads have 18 degree valve angles. You will need to take this into account for piston selection or measuring of piston to valve clearance. Fly cutting the pistons to 15 degree eyebrows may be needed with 18 degree valve angle pistons.

 

[Garrett Ellison]

In other difference that is not easy to see visually is the 48 degree heads have a 15 degree valve angle where the stock and most other aftermarket heads have 18 degree valve angles. You will need to take this into account for piston selection or measuring of piston to valve clearance. Fly cutting the pistons ton15 degree eyebrows may be needed with 18 degree valve angle pistons.

I'm curious if 15 degree LS pistons would have the valve relief locations in the correct location.

 

[Newbomb Turk]

I'm curious if 15 degree LS pistons would have the valve relief locations in the correct location.

I think the valve spacing is different.