Mopar Jimmy

Most know that when it comes to forced induction aftermarket LS series heads are not nearly as important as they are with N/A applications, and that stock LS6 heads make BIG POWER on boost (just look for my sig on bone stock LS6 motor in my 02 Z06).

I am having a forged 347 LS6 shortblock with 224/230, 114 +2, .581/.592 comp blower cam, and for now am planning to run my stock LS6 heads, and should make close to 700rwhp on 12 lbs of boost (and 700rwhp is my goal). Million dollar questions, is it worth the $1,200 to $1,800.00 + dollars to get some Patriot ported LS6 heads, Dart 225s, AFRs, Ported TEA heads to run on my new set-up or not.

I am thinking not on a street car that sees 98% of its life on streets/highway, but do want to have the most responsive set-up for performance on and off the boost and are aftermarket heads worth head for the same set-up I will run on my forged motor, D1SC Cent. Superhcarger kit from East Coast Supercharging!

If yes, what heads would work great and are a great value and I don't want LQ9 72cc heads, as I am looking to make more power with less boost, and I am staying with a higher compression (tham most) between 10 to 10:5 t 1, which makes BIG POWER with a boost (as proven on my stock LS6 motor)!

Lynch Z06

I have AFR 205's. I will have my car's power numbers soon. We will know then.

mdhmi

I think the large number of cars running 9's or better on LS6 heads answers your question. Will AFR heads buy you a little thicker deck and a little more power under the curve? Sure, but at a cost of nearly $2,500. I think you can reach your goals with LS6 heads.

Sportsdude

longdrive70

I have TEA ported LS6 heads on my setup which is putting down about 830rwhp. Though I had to buy some used LS6 heads...after the porting job...the price difference between my worked LS6 heads and a good aftermarket set was about $500....For the extra $$$ I would have rather had gone with AFR's for the thicker deck...Not dissappointed her with my choice as I am very happy with the results

Mopar Jimmy

I think your right and welcome back MARK from your vacation!

peter pan

I had those 99 LS1 Heads and I went with the middle of the road West Coast Heads worked over for a blower, so I think 700 rwhp should be a walk in the park for you and unless you want the bragging rights of I got Trick Flow etc the LS6 will get you where you want to be

RJW

A couple of other factors enter into the equation....mostly from a PD blower point of view, but nonetheless worth mentioning.

Heads that don't breath = need to turn up the boost to make power

This brings several things into the equation

1) Belt issues...now you may be looking at 8 rib setup and/or more power to drive.

2) Pushing water....a gray area, but some get away with 15 to 20 psi and others push water at 12

So the thicker deck heads = less chance of pushing water.

The same can be said for cam and displacement.

Theoretical examples:

Small displacement (346) and/or mild cam and/or restrictive heads = 650hp @ 12 psi

Large displacement (402+) and/or wilder cam and/or heads that breath = 650 hp @ 6 psi

So, if your goal is 700 ish with high CR, then look at the BIG picture.

An investment in heads could balance out in the end, if you can flow air, make your numbers and avoid costly belt setups, sealing issues, etc.

On my current setup, for example... I managed 621/647 on a load bearing dyno before I ran out of fuel. I guestimate close to 700 and at 8 to 10 psi.

Also look at the sweet spot of your blower..keping in the HIGH efficiency range = more almost free power.

The maggie is a classic example. out of the sweet spot = costly belt drive, heat issues, etc.

We just did one on a forged 346 with fairly wild cam and ported LS6 heads. At the moment, it is probably around 600 rwhp @4 psi and heat is contained.

Just some food for thought...this has all been beat to death, but still worth throwing ut.

Look at the BIG picture and what it costs to get there, before investing or not investing in components and findling out the hard way that the supporting mods end up costing more in the long run

jmo

bowmanized

What compression does 72cc give you?

blu00rdstr

I was running 14psi and not pushing water with my West Coast / A&A Stage 2 heads. They're 70cc. I had them rebuilt and they're still in the box, they're for sale for half the price mdhmi mentioned earlier.
http://forums.corvetteforum.com/show....php?t=1817566

Only problem was I was also running dished pistons, so CR was about 8.5:1 with these heads, and rwhp was only about 650 with 14psi. As RJW mentioned low CR needs lots of boost, which means lots of strain on the belt setup and an early upgrade to 8-rib.

The advantage of larger chamber heads is you can use flat top forged pistons, and you can de-mod your car when you sell it by swapping the heads. A dished piston setup is harder to demod, it's harder to sell an NA car with 9:1CR.

RJW

I guess that I should add something as far as pushing water

Some claim to make BIG boost without problems and others complain that they are pushing water.

There could be numerous factors, including flatness of mating components, gaskets and very likely, differences in tunes.....bad tunes/pushing the limits = possible detonation.

It also seems that there is a variety of torque specs floating around as well, along with various sealers, etc.

So much info and mis-info that you just have to go with what you feel comfortable with or who you believe.

My go to guy is a local nascar engine builder who will remain anonymous and who screams at me whenever I ask him questions that start with ' I read or I heard'

He then gives me the 10 minute 'stay off the dam Internet ' speach...

CraZee ZO6

I think someone should try TRICKFLOW heads in a boosted application and see record breaking #s...

madmatt9471

I think that without my TFS Heads 215's that I'm running there would be no way for my '98 A4 to make what it did the other day and I'm at 10.9 Compression too on 6.8 PSI Boost!

The TFS heads are not cheap but they will flow so freaking good, and I'll stand by that!

They are the best heads I've ran since my DARTS! Next choice would be the AFR's!

EXAMPLE: Keith over at LAPD had a set of Patriot Heads on his and he slapped on a set of TFS's 215's and he picked up 34 HP @ the RW's! Dyno to prove it!

I'd go with those or something comprable, Future plans will be easier to go to with a excellent set of heads!

Thanks,Matt

CraZee ZO6

Come one ECS hook up your man with some trickflow 215s and lets see some killer 347 boosted #s!!!!!




TRICKFLOW FTW!!!

FactoryRaceCar

Jim you dont need anything exotic. With your selection of cam and the compression ratio, you are all set and will be seeing numbers over 700 with 12 to 13 psi of boost. Save your $$$ and stick with your LS6 heads.

CraZee ZO6

Anything with boost can make power.

To some its all about efficiency and the few extra bucks to make MORE power on 12lbs than what a ls6 head is making on 14+ is worth it in the end.
Less boost is your friend if your trying to build a combo that lasts.


12lbs on 9.9 or 10.1 comp is going to be NASTY. I beleive with a setup like this in mind the trickflows will prove themselves to be easily worth it.

RJW

Closer you are to the sweet spot...makes for a happy combo....