racecar

Chevrolet sells CNC ported LS6 heads with a 62cc chamber (88958665)
or with a 60cc chamber. They have some pretty good flow numbers.
Anybody out there have any experience with these, good or bad.
I'm building a 12:1 CR road race motor with a 237/242 .595 cam. Would this be a good choice for heads.

Racecar 99 C5 M6, SCCA cage, TPIS headers, no cats, Borla 3",
dual air filters, smooth bellows, 80mm TB.

FASTONE

Those heads flow stalls at about .500 because they were designed for the ASA cam with .525 lift.They also have a rather large intake port that kills velocity(throttle response)also they are milled about .060 I believe which could cause P to v clearance issues and a thinner head deck surface(gasket issues!!)I believe you could find a better head for your plans, such as the 205 AFR,the new Racetech head sounds good and maybe some of TEA"s heads,maybe the 5.3"s.

jbuckweiser

I have those heads with the 59cc chambers and they are milled .055. I agree with fastone regarding the cam your planning to run and p/v issues without checking. Alot of guys still bash the Hot Cam but That was why I chose that cam and I was also wanting roller rockers regardless of what cam so I went ahead with 1.8 ratio. I know Dyno numbers are just that, but I don't think 411hp &383tq @ 2200 ft. is too bad.

racecar

Thanks for the input guys, this is what I want to hear. I have a new LS6 block and crank, Manley forged rods, and JE pistons with a 8cc dome. I can get 12:1 CR with a 62cc head. I will definately check the P/V clearance, oh yes. When the piston hits the valve, it's all over except the oil sweep on the track. I'm interested to hear how these heads perform at all rpm 3000-7000. They look like a good bargin, but what is the downside. I am trying to race without credit cards this time, so cost is important.

jbuckweiser

With Hotcam&1.8 the rev limiter set@6800. It pulls hard over 63-6500. I'm
sure the 11.25 c.r. helps too. Also the custom tune w/30#SVO's. Nailing throttle@ 2200 in first tires start breaking loose. Hope this helps.

FASTONE

If the AFR 205"are too much(2195.00)then look into the Racetech head, some guys(Gomer)were talking about it about 2 weeks ago and it sounded real strong like 460??rwhp Gomer said it was sick fast!!They also offer a cam too.Look over >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

44mag

iTrader: (1)

id like to try these heads to but there actually more expensive than most ported heads on the market like patriot,forcefed, etc. id like to see what they would do with my asa cam.

under_construction

iTrader: (1)

The milling hurts cam selection, and also the flow and port finish is not the best for the dollar. Looks at AFR's, TEA's , APE etc. A good 5.3 head will work nicely, cost less, and put down more power through the rev range. The AFRs are great at a good price. Other ported LS6's just cost too much without cores.

Don't forget to dry sump/accusump if you will be tracking that beast.

racecar

Good call on the Accusump, I was just looking at their web site yesterday. I ran 2 25 minute races this year with the stock motor. The oil pressure seems to be OK, but it is hard to drive with one eye on the gage in every corner. An accusump will be cheap insurance, especially with a new high rev motor, and improvements to the suspension to generate more corner speed. Thanks

Ed Potter @ LPE

iTrader: (1)

Maybe I can help answer some of these questions. We do all of the CNC ported LS6 heads for GM, and they have proven to be an excellent deal. These are NEW LS6 castings that we fully CNC port, 3 angle valve job, and re-assemble using the sodium filled light weight GM valves. You can buy these for approx. $985.00 per head complete through any GM Performance dealer.

Someone posted that these heads fall off after .500 lift, this is simply untrue.
Here are some flow numbers:

400 276 205
450 288 213
500 294 220
550 307 224
600 314 225

these are standard numbers, in fact another member - J-ROD did an independant spreadsheet a while back comparing several vendors heads, and these heads were flowed on a competitors flowbench, I think MTI. He showed similar numbers to what I listed above.

As for the price, I seriously doubt anybody is selling new LS6 castings, New LS6 valves & springs, fully CNC ported and assembled for less than $1,900.00 outright.
Hopefully this helps, but feel free to conntact me if I can answer any questions,

Thanks,
Ed

JS

iTrader: (4)

I have to agree with Ed,these heads are awesome with the right cam selection.

black_knight

iTrader: (1)

Your wording is unclear to me: is that $985 for a set of heads or $985 PER head? Because who would want just one head?

Ed Potter @ LPE

iTrader: (1)

Sorry black_knight,

That price is $985.00 Per head, GM just assumes you will buy 2 of them!

I really don't know why they price them that way, but even when you add them together $1,900.00 is a killer price for what you are getting.

Ed

FASTONE

Those are good numbers,what is the port volume??Also maybe I got mixed up with another ls6 CNC head from GM.Still not very popular,I'd like to see some dyno numbers.I know LPE makes good HP!!!!

jbuckweiser

guys 411hp 383tq @2200# Spokane Valley Enough said!!!

PREDATOR-Z

Do you carry these heads???, I think that would go nicely in conjuction with your $2095 shortblock.

Ed Potter @ LPE

iTrader: (1)

Sweet numbers on the 411/383, what cam are you using?

We don't carry the heads, but you can get them at any GM performance parts dealer for that price! Call Scoggin-Dickey they usually have them in stock.
These would go great with the new line of shortblocks, here's a couple new ones:

http://www.lingenfelter.com/packages01_short.asp

That's a smokin' deal on the 383, throw on a set of the GM/LPE heads and our GT1-1 cam and you will have a real fire breather!

Port volume on the GM heads is 244cc int/ 85cc exh

I'm sure a few members out there have these installed, maybe we could get some more independant numbers


Ed

robertbartsch

I have the Lingfelter ported GM heads that are milled .055.

I have had them on for about 1.5 years - no issues here... I have a street cam so the milling thing is not an issue for me....

they sell one at a time since the right head is the same as the left...

jbuckweiser

ED, I have YOUR heads milled o.o55 and have the HOTCamw/1.8 RR,s. With the 11/1+ compression and cam it pulls hard above 2000RPM,s. No B.S. just the FACTS!

HioSSilver

iTrader: (8)

my buddy Phill has these heads and a grand am cup cam and made 450rwhp & 392 rwtq. Hay ED have you guys ever tried these on a stock ls6 'cause I have a ls6 in a camaro ss and could be interesyed in a set if I could get some hard #'s on them. Buy the way my stock ls6 with bolt-ons makes 407rwhp & 388rwtq.