poly heads

[johnny ga]

can 318 poly heads be installed on a la 318 block

 

[pnora]

can 318 poly heads be installed on a la 318 block

No.

 

[RJRENTON]

can 318 poly heads be installed on a la 318 block

NO......WHY WOULD YOU WANT TO? .....out of curiosity??
BOB RENTON

 

[Lefty71]

Mopar 318 polyspherical motor and LA 318 interchange

 

[RJRENTON]

http://[URL][URL]https://1962to1965mopar.ornocar.com/poly318_1.html

[/URL][/URL]

Maybe physically.(motor mounts)....but definitely not the cylinder heads (poly to LA) NOR INTAKE AND EXHAUST MANIFOLDS.......
BOB RENTON

 

[Photon440]

can 318 poly heads be installed on a la 318 block

You'd have to plug or block off a couple of steam passages that don't have corresponding LA block holes, but that isn't a problem.

And because of the different valve orientation, you'd need different pistons. And a one-off cam grind. You'll have to grind pushrod clearance grooves and add an oil drainback line. The heads themselves can be ported to supply 500+ horsepower.

This Hinkle Performance article shows how a bored and stroked LA block with Poly heads turns into a 426 cubic inch engine pumping out 550 horsepower. https://www.motortrend.com/how-to/426-cube-318-poly-can-outgun-hemis/

 

[pnora]

You'd have to plug or block off a couple of steam passages that don't have corresponding LA block holes, but that isn't a problem.
View attachment 1685026
And because of the different valve orientation, you'd need different pistons. And a one-off cam grind. You'll have to grind pushrod clearance grooves and add an oil drainback line. The heads themselves can be ported to supply 500+ horsepower.

This Hinkle Performance article shows how a bored and stroked LA block with Poly heads turns into a 426 cubic inch engine pumping out 550 horsepower. https://www.motortrend.com/how-to/426-cube-318-poly-can-outgun-hemis/

I remember reading that article a long time ago. Someone had to of been bored with a lot of time and money to spend. There are to many options now days for heads that can make power off the shelf let alone the cost of all the custom parts and machining. Machine shop costs alone will kill a guy.

 

[toolmanmike]

You'd have to plug or block off a couple of steam passages that don't have corresponding LA block holes, but that isn't a problem.
View attachment 1685026
And because of the different valve orientation, you'd need different pistons. And a one-off cam grind. You'll have to grind pushrod clearance grooves and add an oil drainback line. The heads themselves can be ported to supply 500+ horsepower.

This Hinkle Performance article shows how a bored and stroked LA block with Poly heads turns into a 426 cubic inch engine pumping out 550 horsepower. https://www.motortrend.com/how-to/426-cube-318-poly-can-outgun-hemis/

So basically, not compatible.

 

[johnny ga]

just woundering

 

[toolmanmike]

can 318 poly heads be installed on a la 318 block

You obviously have a 318 LA engine. What are you building?

 

[johnny ga]

You obviously have a 318 LA engine. What are you building?

318 30over 1977 out of my dads car crane cam portosonic intake 600 cfm carb hooker headers

 

[RemCharger]

You'd have to plug or block off a couple of steam passages that don't have corresponding LA block holes, but that isn't a problem.
View attachment 1685026
And because of the different valve orientation, you'd need different pistons. And a one-off cam grind. You'll have to grind pushrod clearance grooves and add an oil drainback line. The heads themselves can be ported to supply 500+ horsepower.

This Hinkle Performance article shows how a bored and stroked LA block with Poly heads turns into a 426 cubic inch engine pumping out 550 horsepower. https://www.motortrend.com/how-to/426-cube-318-poly-can-outgun-hemis/

Interesting that article claims they never made hyd cams in those..