wcryan

iTrader: (2)

I thought I was just gonna do a cam on my car but since we have to do valve springs and such my installer said we might as well do the heads too. Not being super motor savvy. If I take my ls2 heads and get them cnc'd is that just as good? Or close to, getting total different heads. The reason being is that I've heard people talk about l92 heads on the forum. It's gonna cost me around 1k to get my heads cnc'd but there are a set of l76 l92 cylinder heads on eBay for cheaper than the cost of getting my stock heads done. Another thing is if getting my stock heads done is better than buying the ones on eBay I have no problem forking out the money. I just don't know what's better
Thanks,
Ryan

raven154

iTrader: (14)

If you go L92, you also need an LS3 intake so keep that in mind. You have 243 castings right now and that what a lot of people sell are CNC'd 243 heads. Obviously they won't flow like the L92's or a set of TFS, TEA, or AFR heads but it will get some nice gains. Now, I am far from a head expert, but 243's don't flow too bad right out of the box. Personally I would do head work unless you could go to a bigger valve as well.

EasyZ06

iTrader: (2)

Patriot has some nice heads starting at about 900 for our cars. Might want to take a look at those. Then you could probably sell your stock heads if they are in good shape and get some $$ back. Just my .02

wcryan

iTrader: (2)

So it would be better to buy new heads other than get mine cnc'd?

-T-

iTrader: (2)

CC'ing your heads will increase your compression. Porting your heads will increase intake and exhaust flow. Both will produce more power. Most aftermarket heads are cnc'd 243's. If your shop can work your heads over, I'd tell them to have at it. For every point (0.1) you raise in compression, your looking at 3-4% tq increase compounded. You can only cc your heads so much before PTV becomes an issue, so the other option is porting the runners for increased flow. I believe it was Lingenfelter that was quoted saying: a great cam and mild heads will make mild power, a mild cam and great heads will make great power. Heads will make a world of difference on your LS2 due to the extra cubes. If your gonna pay a shop to do the work, do it once, that the labor isn't compounded over several mods. They have to remove the heads and re-install, why not re-install a fresh set of power makers!

Any good machine shop can reproduce a set of 243's of patriot, tfs, afr etc... With minimal differences in power.

Dint quote me, but I recall the following from my research, cc'ing chambers is directed towards tq throughout the band. Porting is going to increase tq/hp at the upper end due the heads already supplying enough airflow at low rpm's. Its when you start spinning up that the cylinder air intake is restricted.

wcryan

iTrader: (2)

Love this website. Always get great answers. So I should Tell him I want cnc'd and porting for my heads?

Stepside

Newer Heads = BBB --- Bigger-Better-Blower for future installation.

siggyfreud

iTrader: (1)

CNC is a precision type of porting done by a computer aided machine. Tell him you want your heads CNC ported .

CC refers to your combustion chambers.

raven154

iTrader: (14)

CC'ing your heads wont do anything. All that does is tell you how big the chamber is. CNC'd heads is porting but instead of doing it by hand, you are using a CNC machine. Depending on how the program is written depends on where and how much material is removed from the head. Usually CNC porting actually lowers compression just slightly because they blend the bowls most of the time. Decking the head will remove material from the head to block mating surface and restore the compression lost by blending and depending on how much material is removed will determine how much your compression will increase. Like you said, if you take off to much material, PTV clearance can become an issue but that would take a lot of material, however, that is not called CC'ing.

raven154

iTrader: (14)

lol I type too slow

raven154

iTrader: (14)

: ) L92 heads means LSA or LS9 blower would bolt right on!!!!!!!!

wcryan

iTrader: (2)

Ok. I'll look into some heads. But I'm thinking I'm prolly just gonna use my LS2 heads

babrown18

Best bang for the buck is advanced induction heads can't go wrong there

wcryan

iTrader: (2)

Advanced induction?

lubelizard

iTrader: (5)

Advance Induction is a company that can CNC port your 243s. Another outstanding company that can CNC port your 243s is TEA-Total Engine Airflow. You do not need oversized valves with the CNC work. Stock sized valves with a TEA CNC porting would see 320cfm at .600 lift on the intake. Your intake manifold will be the bottleneck. A minimum of a ported LS2 intake manifold would be the best bang for the buck addition to realize the full potential of the heads and intake. For $1000, TEA will port the heads, shave the head surface for 62cc's, install PAC beehive springs, and "rebuild" the heads. I'm sure AI has a similar deal. A ported LS2 intake is probably going to run $350 with a core exchange through FasterProms. If you were to buy the L92 heads off ebay, you would AT LEAST have to send them out to have them checked, and I thin the combustion chambers are larger than the OEM 243s, which would reduce your static compression ratio, but I am not absolutely sure about the L92 combustion chamber size.

siggyfreud

iTrader: (1)

Seriously? So our heads are what is limiting us to the Maggie 112? Would those other blows clear the rest of the underhood area? Now you've got my interest perked!

wcryan

iTrader: (2)

The install will consist of a mediocre to aggressive cam. Stock heads. But ported etc etc and headers. Think I'll get 450rwhp? That's what I'm looking for

-T-

iTrader: (2)

There seems to be some misconceptions. So cc'ing your heads is only telling you what your cumbustion chamber size is...not cc'ing to spec; but cnc'ing your heads is porting your runners to spec but not telling you what volume they are? It goes both ways guys! CNC spec your runners to what volume? CC your chambers to what volume? Its the same catch all as cc'ing your chambers. You cc your chambers and cnc port your heads to specs.

For instance, i want to cc my chambers and get my runners cnc ported.

Specs: 62cc chambers, 215cc intake runners and 84cc exhaust runners

Those specs right there that I will get my heads worked to are identical to PRC's 215cc heads sold by TSP for $2200.

Why spend $2200 at TSP when I can have my machine shop do my heads for $500 a head? I'm not gonna get $1200 for my used heads. It doesn't make sense to purchase new heads and lose money when I have a reputable shop that can do the work and stand behind it.

OP: Do some searching in the GENIV External forum and look at others heads/cam specs and see what has made the power you want.

SoCA04V

Maggie and be done with it. No smog BS to worry about either....

MIAdragon

iTrader: (6)

Dude "cc" or cubic centimeters, is a form of measurement nothing else, CNC stands for "computer numerical control" or computer controlled porting program. Not the same at all.