Heads, let's talk....

[TylerZ281500]

411 has better parametrics. not worth tuning a stock vortec. i understand the concept of thermodynamics but im still gonna prefer aluminum over iron time adn time again. ive never found a downfall. never saw shortened lifespan either.

i think the best idea is RHS or etecs so far but at that point it would be follish to put the junkass stock intake back on there.

 

[slowburb]

411 has better parametrics. not worth tuning a stock vortec. i understand the concept of thermodynamics but im still gonna prefer aluminum over iron time adn time again. ive never found a downfall. never saw shortened lifespan either.

i think the best idea is RHS or etecs so far but at that point it would be follish to put the junkass stock intake back on there.

See that's the thing. Why put close to $1000 in heads under a really really crummy induction setup?

 

[big_mike]

That's why I was looking at the cheaper Summit castings or working the stock heads. This motor isn't being built to make alot of power, if it pumps out a solid 350ish I'll be plenty happy.

It's just a daily driver that is used to tow sometimes. My wife will drive it half the time so it has to be pretty tame.

I'll worry about big power when I get my next fbody and LS base to work with. Right now I just want to build a solid reliable combo with a slight bump in performance over stock, that's all.

What about the actual GM castings Scroggins still sells, I looked at those and they have a set priced right about the same as the Summits fully dressed. Anyone ran a set of those?

I'd like to only have about $600 wrapped up in heads for this project.

 

[slowburb]

$600 for heads means buy a set of GM vortecs from the cheapest place you can find and don't look back.

 

[big_mike]

Seems like Scroggins, Summit and everyone sells them fully dressed for about $320 per head.

CHEVROLET PERFORMANCE 12558060 - CAST IRON L31 VORTEC SB

After reading it seems most who bought these reported they are 062 castings, 170 runners with 64 chambers.

So that really just a new out of the box stock vortec head right?

 

[slowburb]

Mine are.

 

[big_mike]

Do those still have the press in rocker studs or screw in? I can't find that on Scroggins or Summit, only that rocker studs are included.

So now comes the question of, for the same price would the Summit (Dart) not outperform the GM 12558060 since they have a slightly bigger runner size? Or is it a wash since they have a slightly larger 67cc chamber which would slightly lower compression over the 64cc on the GM head if the same gasket was used for both?? Also who's finished head quality is better??

I have read people pleased with both sets, some ran them right outta the box others did a little cleanup before install.

 

[slowburb]

The big time chevy dealership that sells go fast parts is Scoggins Dickey. Not Scroggins Dickey.

The need for screw in studs on vortec heads is a wive's tale. Especially with the factory cam and valvetrain. The spring pressures are next to nothing. I'd only concern myself with screw in studs if I was running a cam with well over .550" of valve lift. I'm running 1.6:1 rockers on the '395 cam and will have no issues, even with the upgraded springs I put on. Hundreds of thousands of vortec heads have the ghetto grind or some other mods to run the HOT cam (lift over .500"), and are doing so with the factory press in studs. Bottom line, don't concern yourself with screw in studs because it is unnecessary overkill.

The runner volume on the dart heads does not outperform the chamber shape & port shape on a REAL vortec head. Period.

Make sure you use the GM 0.028" compressed thickness head gaskets and the FelPro MS98000T intake manifold gaskets.

 

[big_mike]

That's the cam I'm looking at running as well. What kind of gain did you get switching rocker ratio with that cam? Are you just running a standard timing chain too?

I though the Summit heads did have a true vortec kidney shaped chamber with centered plug? I thought only difference was thicker casting and no "ramp" in the intake port like the stock casting has.

 

[slowburb]

Rockers went in when I did the cam swap, so I can't answer your question. Yes, stock replacement timing set. I don't know anything about a "ramp" in the vortec intake ports. The TBI swirl port '193 heads have ramps in the intake ports. Man, leave the summit/dart heads alone.