C6nexttime

Advanced induction is the place to go get your 243's done. Over on the gto boards AI ported 243 heads are on some of the fastest gto's. TEA (total engine airflow) is probobly just as good. I only give AI the nod because they designed that port originally for gm. They know the head. Both places will do you up good and cost about 1200. I have talked to both and they both told me when you already have 243 heads there is no point in buying an aftermarket casting, Heard it from brian tooley himself. Ask ecs how they like the TEA 243's.

AirBusPilot

I thought stock head LS3's were getting 500 rwhp with a 230 spin cam and stock intake manifold? 6.2L v. 6.0L, but it should be close to that?

Joe_G

No. Stock ls2's are about 340. Ls3's are 380 which is about what ls2's make with full bolt ons except Fast intake. When you add a sizable cam to both the ls2 is 450 ish to 470 and the ls3 is 480 ish and some get close to 500.

The additional cubes help a lot.

musicman2

THANKS !! for this info------will check them out !!

LSCHLEM

Just one more thing. The stock or reworked 243 Heads will have poor resell
value. By the time you are done you will have spent close to the cost of the TF 225's. You can sell your stock heads and add to that to get the
TF's. They will make so much more power. I got about 50 rw from the trick flows and the 243's had patriot springs etc. There is no comparison as the TF's and the FAST 102 took me to 507 RWHP.

C6nexttime

Here ya go man, gto with AI heads through a stall. 503rwhp
http://www.ls1tech.com/forums/dynamo...st-2009-a.html

Another gto with AI ported heads and vrx5 cam put down 494rwhp

The tfs heads are a very nice piece and so are the afr 230 heads but both come at a substantial price increase. The tfs require roller rockers which brings the cost up to 2900 and the pat g afr 230 head was custom tweaked and cost 3600. They are not worth 2k more.

Mez

A few of the aftermarket head manufacturers recommend roller rockers with cams that have lift over .550 inch to improve the geometry and reduce side loads on the guides. According to what I have read, stock rockers have less than ideal geometry as lift increases beyond .550 inch and more valve guide wear. So if you are using the 243 heads with a higher life cam, like me, roller rockers are recommended.

From a cost vs. power increase perspective, its hard not to go with aftermarket heads. However, you can make the mistake of going with the wrong ones. The other day, I learned of a LS1 Corvette with big port stage III heads that made 20 less RWHP than a set of smaller, ported GM heads. Bigger heads are not always better. Velocity is the name of the game and to maximize torque and power, the port size has to be right.

musicman2

HEY ---THANKS AGAIN !! Sent you a PM

AirBusPilot

I just keep hearing about how the LS3 head is so inferior to these aftermarket heads, but 500 rwhp is easily achieved with a mild cam and the stock LS3 heads.

Also, the hp difference between and LS2 and LS3 has alot to do with the LS3 heads, not so much 0.2 L, IMO.

riggs 74

Is the LS3 (823) head really producing 500rwhp stock with bolt ons?
I looked the other day at the LS3 heads and seen that I could
pick up a set new for around 1600 and I just looked at some used
sources and found them for under a thousand.

I was hoping to stay with the 243 castings, and may still do that
but I don't want any regrets later after the build is all complete.

Keep the Information coming, I appreciate all input.


Riggs.

oldmansan

I'd listen to Spin. If Spin told me I was spelling my name wrong I'd probably have to change my name. There are those that know what they're talking about, and then there's Spin.

Spin's probably the only person I've never met personally that I'd leave my Corvette with. He drips of professionalism and integrity. He stands behind any work he's ever done, and that's something missing from almost everyone.

San

AirBusPilot

Spinmonster designed a 230 cam for AndrewZPSU's 08' LS3. Stock LS3 heads, just cam, headers, cai, CB and DR's and he ran 11.1 at 129 mph (504 rwhp). Great drivability.

Spin himself above seems to think there are better heads, but with results like Andrew's car, I don't see the problem

http://forums.corvetteforum.com/c6-t...p-records.html

The above quote by Spin is from the link and it is referencing Andrew's stock head LS3 car.

Considering the large price difference between off the shelf LS3 heads and aftermarket, I don't see much value of upgrading to aftermarket and only gain a few hp. Maybe Spin will clarify this.

PRE-Z06

you've made enough passes in a manual to know driver shift speed and track prep effect mph, plus comparing mph from all over the country in different weather conditions isn't exactly a fair judgement imho...fwiw we've had a 5.7l gto make 495rwhp with TSP 243s and a mid 230s cam

C6nexttime

The ls3 head is awesome but many people screw up and use 1 7/8 headers. The 1.59 exhaust valve in the ls3 heads likes 1 3/4 headers better. If you notice some of the fast spin cam cars are using 1 3/4 headers.

Neumonic2002

I remember Patrick G showing a LS2 car that did 503 rwhp with stock 243 heads: http://www.ls1tech.com/forums/dynamo...s-503rwhp.html

I read the long thread about LS2 VS. LS3 heads and came away thinking the LS3 style head shines on a larger displacement and the 243 style head is tough to beat on a 4" bore LS2.

Mopower2007

I Have 243 heads enhanced by Performance Induction to LMR's stage 3R spec's, comp cams 54-459-11 (LSR) camshaft, Fast 90 unported intake with LG 1.75" headers, 6 speed tranny. Car layed down 487 rwhp & 440 rwtq thru 3.90 gears in the middle of the Texas summer. Very streetable, this cam isn't designed for max HP. Factory heads can perform for less money. If FI was in the cars future I believe aftermarket heads are better because of a thicker deck. I have no regrets. Just my .02 cents.
http://www.youtube.com/watch?v=jXfkePZR5bA

riggs 74

I wanted to stop back in and say thanks for a the guidance. I will
need you help again in the future and hope that I don't become a
pest.

Thanks guys
Riggs.

CTD

I sent you a PM, I have a used set of used Mamofied AFR 205's coming up for sale shortly.

JayplaySS2

231/239 is your cam design and since I am thinking of an EPS lob'd 233/239, I have to ask- How are the street manners? I know you say it's streetable but more input would be cool. What rockers and push rods are you running? What cai as well? What cc chambers?

With a 102, rockers, stout pushrods and a SD tune, I can see picking up some good power.

Thank you-

Jason

Mopower2007

My cam is the Comp Cams 281LR HR13 (231/239 & .617/.624), Stage 3R LS6 heads (2.10 int/ 1.575 ex with 240 cc runners) milled for static CR of 11.2:1 done by Performance Induction. Comp pushrods & lifters. Stock rockers.UD pulley. 160 deg stat. Ron Davis radiator. Unported Fast 90. RPS twin disc carbon clutch. LG Pro longtube headers. Varam CAI. DTE stage 3 differential w/ 3.90's. Toyo R888 rear tires (stick like glue on the street).

Car sounds awesome at idle with some body shake, no driveabilty issues at all concerning the cam, and runs like a bat outta he!!.The RPS clutch is like a light switch. On or off. That took some getting used to, nothing to do with the cam. Again, I have no regrets and can only share with you the results of my build which I'm very pleased with. Good luck and hope this helps. PS- Best advise I can give you is seek professional advice, use internet forums for info only.