Help spec'ing out a new small block

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Can the block be notched ?
I had to notch my 4.375 bore 400 for my trickflows about .100 .
Are you saying you "had" to notch the bores for clearance? Or did you choose to notch the bores for unshrouding purposes?

Newbomb Turk mentioned moving the valve center on the larger valves in small block heads. That is something I understand but had not considered on the Victor heads. Does anyone know if the valve center on the intake, or the intake and exhaust, were moved on the Victor small head? I have not seen that mentioned anywhere yet but they do say the heads were intended to use a big block style rocker arm and a 16 degree valve angle, so who knows.

The engine that Valley performance built with Victor heads supposedly used a 4.10" bore, so we know they "fit" in that bore size.
 
Are you saying you "had" to notch the bores for clearance? Or did you choose to notch the bores for unshrouding purposes?

Newbomb Turk mentioned moving the valve center on the larger valves in small block heads. That is something I understand but had not considered on the Victor heads. Does anyone know if the valve center on the intake, or the intake and exhaust, were moved on the Victor small head? I have not seen that mentioned anywhere yet but they do say the heads were intended to use a big block style rocker arm and a 16 degree valve angle, so who knows.

The engine that Valley performance built with Victor heads supposedly used a 4.10" bore, so we know they "fit" in that bore size.
They would have to be moved, half of a 2.15 + half a 1.6 = 1.875" and stock spacing is 1.87" that's leave less than zero room between valves.
 
Are you saying you "had" to notch the bores for clearance? Or did you choose to notch the bores for unshrouding purposes?

Newbomb Turk mentioned moving the valve center on the larger valves in small block heads. That is something I understand but had not considered on the Victor heads. Does anyone know if the valve center on the intake, or the intake and exhaust, were moved on the Victor small head? I have not seen that mentioned anywhere yet but they do say the heads were intended to use a big block style rocker arm and a 16 degree valve angle, so who knows.

The engine that Valley performance built with Victor heads supposedly used a 4.10" bore, so we know they "fit" in that bore size.
Mine was basically by choice because it wasn't right. For unshrowding
 
The valves fit without issue…this is on my dead mock up block with 4.03. New one is 4.09, so there’ll be just a little more room (030 on the edge ain’t much though). Sorry, best pic I could get at the moment:
1704335792550.jpeg

Whether or not you think you want to notch for shrouding is up to you, but Valley didn’t on their EM motor and it did pretty well.
 
The valves fit without issue…this is on my dead mock up block with 4.03. New one is 4.09, so there’ll be just a little more room (030 on the edge ain’t much though). Sorry, best pic I could get at the moment:
View attachment 1716187534
Whether or not you think you want to notch for shrouding is up to you, but Valley didn’t on their EM motor and it did pretty well.

I thought the EM engine was a bigger bore.
 
The radius of a 2.15" is 0.035" to 0.065" larger than 2.08"/2.02" meaning to keep about the same bore shrouding, you need about 0.070" to 0.130" larger bore if intake valve hasn't been moved over.
 
The radius of a 2.15" is 0.035" to 0.065" larger than 2.08"/2.02" meaning to keep about the same bore shrouding need a 0.70" to 0.130" larger bore if intake valve hasn't been moved over.
Grab that article for Pittsburghracer for the cid… 378 IIRC
A slight destrok of the 3.58 crank and a 4.1 bore… *I Think!*
 
I thought the EM engine was a bigger bore.
Yes it was; 4.1. So, I guess you could say they put in a 50 thou notch? But if Bill is gonna build a new block, or even stay with the current one there’s going to be some over bore (full diameter notch work) anyhow.

Not sure how much (if any) Edelbrock moved the valves on these heads. The intake seat overlaps/is cut into the exhaust seat, so the valves dang near kiss each other.
 
They would have to be moved, half of a 2.15 + half a 1.6 = 1.875" and stock spacing is 1.87" that's leave less than zero room between valves.
Measuring mine I have 1.9438 spacing between valves on a 1.25 bore
 
Yes it was; 4.1. So, I guess you could say they put in a 50 thou notch? But if Bill is gonna build a new block, or even stay with the current one there’s going to be some over bore (full diameter notch work) anyhow.

Not sure how much (if any) Edelbrock moved the valves on these heads. The intake seat overlaps/is cut into the exhaust seat, so the valves dang near kiss each other.
I’m calling Edelbrock in the morning and find out if they moved the valves
 
I’m calling Edelbrock in the morning and find out if they moved the valves
Here’s a decent pic from the interwebs of the valves in the chamber…bend one and you’ll toast the other:
1704337658228.png

The offset on the intake rocker alone makes me rather certain there was some movement…no pushrod pinch though!
 
To add on this valve shrouding discussion my flowbench head adapter is a 4.010 cylinder sleeve. I could cheat the system a little and go 4.060
Or even 4.100 and the only one that would know would be me. I’m sure I could squeak a few more bragging numbers to my customers like many do on uncalibrated flowbenchs. I don’t buy into this shrouding as much as some guys because I see what my heads flow with a 2.08 valve or even my bigger valves in my Indy heads.
 
I agree. Don’t worry about valve shrouding. Avoid it if you can but it’s not the end all or huge power killer.
 
As long your gaining more in the unshrouded places than losing in the shrouded should be a net gain.
 
I’m calling Edelbrock in the morning and find out if they moved the valves

They pretty much had to. You can get a 2.100 and 1.600 valve in there but your machine work has to be impeccable and even then you may see some witness marks of the margins just lovingly scraping each other.
 
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