CAracer

I just purchased some LS-6 heads from Paceparts.
I believe that they are used on the ASI racing circuit.

I haven't received them yet. But, I was hoping someone out there has installed these heads and have some good dyno numbers or results in performance.

Here is more information on the heads: They are CNC ported by Lingenfelter. They are milled .055, which increases the compression ratio to 11.2:1
They have the hollow intake and exhaust valves. They are also specked for .570 lift.

Any information would be appreciated.

Thanking you in advance.

Gold Z

iTrader: (3)

I've got a set going on a motor we're building for my car. They were not ready to use right out of the box. There are some sharp edges in the combustion chamber around the sparkpug threads. Also the CNC work is very rough. The stock LS6 springs will work with smaller cams but I personally didn't buy LS6 heads to run a small cam so I replaced the valve springs. After some cleanup work by Trevor Johnson the heads flow good out to .700 lift. All in all I am very pleased with the heads.

robertbartsch

I just bought the same EXACT Lingfelter ported heads from SDPC for $980 per - no core charge...SDPC said they sell 60 sets of these heads per month...I had to wait 10 days for them to ship...

I am replacing the stock LS6 springs with Lunati REV double springs, titanuim retainers, and hardened seats in preparation for a BIG cam...

I have not received the heads yet, however, I am investigating the .055 milled question (problem).

I have been doing surveys to find anyone that has run a .055 milled head with the following cam:

TR 230/224 .560/.560, 114LSA (the TR reverse split)

Basically, only one person was found - he said upon installation that the clay measurement was REALLY close but he had flycut stock pistons...so he said "this cam/head combo ain't going to work as is..."

Well ...if you look at the flow numbers on the heads ...all the extra flow begins to happen at .550 lift ...so I figure ...why buy new ported heads if I cant get a cam that takes full advantage of the new heads...

I am now considering buying extra thick head gaskets to nullify the removal of material from the milling process (why do they do this?) ...Apparently, Cometic sells several extra thick head gasket sizes from .060 (stock) to .124...

Moreover, the forced induction guys run thick gaskets to cut compression, however, they tell me that much over .078 will have bad results - These include poor breathing, pinging, possible blown head gaskets, etc.

Who told you these heads were designed to accept a 560 lift cam????? ...did you verify this with anyone else? What about the impact of a longer duration cam and not just the maximum .560 lift? (I need to know this ASAP)

You can see some of my recent posts under "Robertbartsch" ...look here and also in the forced induction section of this cite...

Thanks...

Zeta

If you do a search on ls1.com, there is a guy with a ASA cam/LPE heads [george]. It has a .525 lift, and that is the cam he says is the cam designed for the LPE heads.

If you are running an long duration high lift cam, you are going to have to cut the pistons. The goal is .08 [intake] and .1 [exhaust] PV clearance.

If you run a smaller cam like a TR 220, you probably will be OK.

Expect the compression increase to increase NOx emissions. You may have not be able to run as much spark advance as you are used to doing. Plugs one heat range lower can help with detonation.

I hope to have hands on experience with all of the issues brought up in the next 6-10 days.

Gold Z

iTrader: (3)

The tag which is attached to each head lists all the specs and states the springs are good to .570 max lift.

OBSSSD

Do either one of you guys want to sell your new set of LS6 springs off your heads? I assume they are the newer 02-03 springs?

Please post or e-mail me if you are.

Thanks!

robertbartsch

....I'm not enamered with the ASA cam with a .525 lift - this seems a lot like the GM Hot cam everyone says is close to the stock LS6.

If the cam I want to use is .560 lift, why can't I use a .090 gasket....that should give me more clearance than the .525 lift cam has with a stock .060 head gasket?

Gold Z

iTrader: (3)

The heads pretty much stop flowing at .550 lift as they come out of the box. With light cleanup work by Trevor Johnson mine are flowing good all the way to .700 lift.
The combustion chambers need to be cleaned up too. the CNC porting is very rough and there are some very sharp edges around the sparkplug hole. Any decent size cam will require a spring change. If anybody needs a set of 2003 LS6 springs and retainers I'll sell mine for $75.

Bink

Ed Potter at lingenfelter said these are the LS6/SCCA heads- used in the Grand Am Cup cars. The cam these heads were flowed for is the Grand Am cam 0.570", 239/251 and 106 LSA.If you install these heads with this cam you will need to notch STOCK pistons ~0.060" intake and ~ 0.100" exhaust(Cup cars don't use stock hypereutectic pistons -forged alloy with valve pockets.)These are 60 cc comb. chambers.
I haven't installed this setup yet. Heads were cleaned up and sanded at Lingenfelters and flow 312 cfm Int and 223 cfm Exh @ 0.600".Not too bad.
<img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" /> <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" /> <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

robertbartsch

...Can fly-cutting the pistons be performed without removing the engine? By whom?

Slowhawk

iTrader: (12)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by robertbartsch:
<strong> ...Can fly-cutting the pistons be performed without removing the engine? By whom? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yes,and by yourself.Isky sells the cutters you need.You turn them by hand and they cut fairly quik.I just had my pistons cut by a friend in the car.

BTW, I have 02LS6's milled .030 and 2.02/1.60 valves running a TR224 cam.Had to cut .050 for the intake valves.