Max Wedge heads on a Street Wedge block

[63SPF]

Aloha my friends, I am about to embark on a new project . I have a 64 / 426 street wedge block , bored 30 over , new forged pistons , H beam rods , 440 steel crank. Comp. 285 /485 cam. etc. and I want to use a set of 63 / 426 stage 1 M/W heads. Q 's is will I have any problems ? Valve to piston clearance ? etc. My pistons are fly cut . I noticed M/W blocks have a cut away in the top of the cylinder , looks like for a valve.

 

[66Satellite47]

It would be wise to "clearance" the bores, if not for pure clearance, but also for the flow improvement.

 

[lewtot184]

block should need an exhaust valve relief at the top of the bore.

 

[63SPF]

So how do I get specks for the exhaust relief for wax wedge ? So I know what , where and how to put it .

 

[396 Signet]

You do not need an exhaust relief for clearance reasons, there is plenty of room with the 4.25" bore. They did that with the idea of improved flow which is subject to debate. I'd leave as-is, too deep & you could be into the ring pack. Out of curiosity I took a pic with the standard heads on my 383 (same bore as 426), of note is that the closed chamber is actually larger than the bore & there's plenty of room for big valves.

 

[63SPF]

Very kool, Nice pict.

 

[Furiousvip]

Just curious what intake you plan on running with those Max Wedge heads?

 

[63SPF]

1963 max wedge cross ram intake , trying to make a 1963 Plymouth Sport Fury convertible Max Wedge clone . I just don't have the 426 M/W block. I only have a 1964 street wedge block. I also have the M/W exhaust manifolds

 

[63SPF]

Out goes the 400 , in comes the 426 .

 

[dvw]

The exhaust valve can hit the bore at 4.25". Assembling one many years ago I heard a squeak while rotating the engine. It was the exhaust valve grazing the bore. Had to grind it.
Doug

 

[63SPF]

Ok, thank you. Now how do I get a picture or a speck sheet to tell me where and how much of the bore to grind. So I can let my Machinist know properly . I have over $5000 invested in this 426 M/W so far and I want it all to go smoothly . Well as smooth as a Max Wedge will run . Ha Ha

 

[63SPF]

Also looking for a set of rocker arms and stands for a early set of Max Wedge heads. If anyone can Please help. Last piece of the puzzle .

 

[lewtot184]

there are bore/lift combo's that 1.81" valve will have issues with. best bet is too mock it up and visually see whats going on. i use a head gasket to lay out bore notches and also measure how far down from the top of the piston the top ring groove is. if those blocks didn't need the notch the factory would have never done it. if i remember correctly the nascar blocks had intake and exhaust notches. the factory cams for those heads had .509" lift, which isn't a lot by today's standards. the valves don't open on center and i think they are canted 15 degrees. a mock-up makes things safe.

 

[63SPF]

thank you for the help

 

[63SPF]

This is for my fellow Max Wedge heads, Some info that was given to me by a good man. Much Mahalo Greg

 

[396 Signet]

Apologies for my misinformation. A dah moment on my part, just saw the side to side clearance & didn't take into account valve angles & lift. Regardless I would do an actual mockup to see exactly what you need with the parts & cam you're using.

 

[63SPF]

I will do, Any and all help is welcome, Mahalo C

 

[383man]

I take it you already have the heads ? I only ask because if you plan to run pump gas you might consider going with a more modern aftermarket aluminum head. Or unless you just want real Max Wedge heads. Aluminum would be better with the pump gas of today. The Max Wedge heads had the 1.88 exh valves and the 64 stage III eng had .520 lift with 300 and 308 advertised duration. I agree with everyone as I would check it real close and notch the cyl bore with a 4.25 bore. Good luck , Ron