I have a set of 781 bb heads they have 2.190/1.180
valve I was thinking of going with a 2.250 intake
do you think this will work or is this to large of
a valve for a stock head
I'm still doing the math on a kick ass 496
and was told that my 2.190/1.188 heads are a little small for this motor size
I still need to buy pistons so if it will work will i need to keep the valve size in mind when buying pistons

Take your pick;

2.19"/1.88",
2.25"/1.88",
2.25"/1.90",
2.25"/1.94" and finally
2.300"/1.88"...

The 2.25"/1.94" should be about max. if they do indeed fit into a stock casting b/c they will a Merlin oval casting...

And I have (8) brand new Manley stock, still in the box, 2.300" intakes if wanted.. Will make a deal on them..

pdq67

pdq...what valves are you running in your 496? I know Ed is using 2.25 intakes in his 215's.

Guys, Bigger valves don't always equal bigger power, especially if those 781's have stock ports in them. Sure they are excellent heads, but you can only flow so much air through them no matter how big you go on the valve. You might actually cause your motor to bog down low if you go to big on the stock heads. Just my 2....

I am just using Manley, stock replacement 2.19"/1.88" valves in my Merlins b/c I'm not going to rpm her much above 55 to maybe 5700rpm so I figure they are fine for my application..

Heck, my CC 282S solid cam per D2K peaks hp at 5500 rpm so why run her much higher...

I thought about installing the 2.300" intakes but figured it was going to be a hassle locally..

And mark is right, you have to rework the bowls and ports to make big valves flow GOOD and worth the installation hassle..

I have an old mag. article about a 505 Super Gas motor that had Merlin ovals opened up to like 324 cc's with bigger valves installed to make her suck good..

pdq67