[chewyscool]

Its time to bolt on some heads to my motor build.
327 .30 over
stock flat tops
comp xe256h cam

I want GMPP vortec heads but what is the max lift for these heads?
I've read here and jegs and summit all different information, just will I be alright with the cam that I have installed?
Shoud I get alm. heads from eddy being that I will be near 10:1 compression?
And will an eddy performer head be equal to their etec? ( if i go alm.)
This motor will be used as a cruiser not track.
Thanks for any advice

[scapegoat]

The run of the mill vortec heads that jegs/summit sells will handle .475 lift. You could look into an RDS pro torker vortec head. The accept either style intake and usually have heavier springs.

http://www.speedwaymotors.com/p/6613...der-Heads.html

[jimfulco]

Scoggin-Dickey sells brand new Vortec heads modified for higher valve lift, and some that are also machined for screw-in rocker studs.

www.sdparts.com , click on engine parts, cylinder heads, SDPC Vortec heads

A flat-top 327 with 64cc heads only has ~9.6:1 CR, GM just rounded it off to 10:1 so it sounded better.

[cool rockin daddy]

You will be fine with stock vortecs with your cam. If you have a vortec style manifold already and want aluminum heads, the Etecs are hard to beat. Superior cathedral style ports mean excellent velocity of the air/fuel mixture. There is a reason that the LS1, LS2, and LS7 engines utilize that style port.

You could also go with the GM Bowtie Vortec heads. 180 cc or 200 cc intake volumes. Can handle much more lift than your cam presently has and you will have room to add more cam in the future. Comparable in price to aluminum edelbrock heads. Do you want cast iron or aluminum heads? Either of these heads will work great. With your cam right now, anything other than stock vortecs would definitely be overkill.

[techinspector1]

Originally Posted by chewyscool

Its time to bolt on some heads to my motor build.
327 .30 over
stock flat tops
comp xe256h cam

I want GMPP vortec heads but what is the max lift for these heads?
I've read here and jegs and summit all different information, just will I be alright with the cam that I have installed?
Shoud I get alm. heads from eddy being that I will be near 10:1 compression?
And will an eddy performer head be equal to their etec? ( if i go alm.)
This motor will be used as a cruiser not track.
Thanks for any advice

General Motors says the lift limit on GM 12558060 heads is 0.0450". You may see some clearance between the retainer and seal at this lift, but remember, you MUST have some clearance at full lift.

[Xero420]

Comp. Cams makes a spring kit that will put it to 0.550 in. on stock heads.

[blndweasel]

Originally Posted by jimfulco

Scoggin-Dickey sells brand new Vortec heads modified for higher valve lift, and some that are also machined for screw-in rocker studs.

www.sdparts.com , click on engine parts, cylinder heads, SDPC Vortec heads

A flat-top 327 with 64cc heads only has ~9.6:1 CR, GM just rounded it off to 10:1 so it sounded better.

I'm running these on my vette, and they're a hard deal to beat... Produce excellent power. Just make sure you set your quench properly.

[Xero420]

I put a set on my 350 with flat tops and got 9:5.1. But I want to up my compression, so I am having the heads re-angled by .5 degree. The shop I have all my work done at told me that I will gain 12 to 14cc for this. But he warned me about the quench.

So what is the quench, and what do I need to look for?

[acr]

Google-"cylinder head quench", then go to the KB-Silvolite Home page for a definition/explanation.

[Nothing's Easy]

These springs have pretty much solved the vortec lift limit. Bee Hive Springs

[DENCOUCH]

There are others cams out there for Vortec heads that don't require any special lift consideration & work well with the stock lift limits.

F-Bird'88 recommends using basic Z28 springs (Cheap-less than $50) for serious Vortec heads. Stock springs are sissy stuff when it comes to open pressures.

The Vortec head comes alive with 45 thou shaved off and bolted back onto the block with a 15 thou Felpro steel shim gasket. Block needs to be flat tho, max 3 thou warp per 6 inches.

All this stuff will give you a great quench using flat top pistons, and work like a dream if you try one of the "Lift Rules" camshafts that Isky has out.

The duration is crazy and the lobe centerline is small, but the new high compression is NP on pump gas!

The initial timing is set at a crazy 26 degrees. Ported Vacuum advance instead of manifold.

Torque monster... tromp the gas & the tires light up. Motor howls and revs with a sense of urgency.

All this HP with little machining or expensive parts.

Priceless!