Red02LS1

https://ls1tech.com/ubb/cgi-bin/ulti...c&f=1&t=002231

I just got done reading that, and Patrick G said some of the cars got LS6 heads due to production over run. Is there a known part # I can check, or something I can look for to see if I have LS6 heads, other than pulling the manifolds to see if the exhaust port is more "D" shaped?

VINCE

iTrader: (1)

I just checked my 01 heads and they are not LS6. Logic tells me that if they put LS6 heads on our cars there will be people dyno'ing closer to 350rwhp from the factory.. In GM High Tech the LS6 heads flow almost 30cfm more than the LS1 head from the factory.. GM does not seem like the people that would go thru a lot of trouble to detune a car just so LS6 heads power do not show up.. Yes the timing is down on the 01's, but not enough to hurt 20rwhp plus.. Just my 2 cents..

LS1derfull

Yes they do have a bigger cam, and if any of us have Ls6 heads we would benefit from lighter valves($) also. A cam swap with those heads would make a huge difference! Almost like free port work! <img src="gr_grin.gif" border="0">

WhiteDiamond

It is just one of those things where somebody is going to find out their car has them someday. The problem is going to be verifing it. GM won't have it listed anywhere at this time, I bet, and GM parts counters are not going to have it listed as well.

I personally believe it is very hard to find fact in this, as GM specifically built the LS6 outside the LS1 assembly in 2001. In late 2001, GM switched over to the LS6 block for all LS1/LS6 vehicles, but as we know, the block doesn't make the horsepower difference. With the truck line and the F-body/LS1 Vette lines all getting basically the same aluninum head, I find it very hard to believe GM ran out of supply and put "limited" production LS6 heads on them.

Todd

VINCE

iTrader: (1)

Do not mean to bust your bubble. My car dyno 318rwhp with the same amount of miles.. I have a friend whos car dyno'd 327rwhp as well and now has 334rwhp with a lot more miles.. We both have LS1 heads..

VINCE

iTrader: (1)

Oh yeah, I did not have a lid on my car..

John B

iTrader: (10)

I'd like to settle this right now.....without even looking at an '02 I would put money on the fact that none will ever receive LS6 heads and be sold as an LS1! Why am I so confident in making this statement?

The '02 LS6 heads are not directly interchangeable with the LS1 valvetrain. Before for you get excited about this and hit the reply button finish reading.....

The '02 LS6 heads have taller valvestems to compensate for the larger lift of the LS6 camshaft. The way GM obtained the added lift was to shrink the base circle of the LS6 cam while maintaining the same pushrod length to minimize creating more unique components. Think about this for a minute, you wouldn't even be able to set the correct valve lash using the F-body cam with '02 LS6 heads because the rocker arms are not adjustable.

And don't try to convince me now that GM might as well install the LS6 cams into the F-body while they are at it! Ain't gonna happen, sorry!

BigBake

Well maybe not the 02's but a good possibility on the 01 heads. If you think about it since they were scraping the old head design from the 01 heads to the new 02 heads it leaves a possibility. No one can seem to explain the high horsepower ratings of the 01's. Everyone thought it was because of the LS6 intake, but for the last year people have been putting on LS6 intakes on there 98 and up, and are not getting the returns like they thought. We also know the cam is a detuned compared to previuos years. We also know that the later 01 seem to be the cars with more power. So where did the extra HP come from? We are seeing cars turn 330 on the dynoes compared to the 290 of the 98-00. That is quite a bit of difference.

QUASAR

iTrader: (6)

Well than i will just have to pull my manifolds off the day i bring it home from the dealer and find out! <img src="gr_grin.gif" border="0">

LS1derfull

REDO2LS1, this answer is like trying to find gold.
I have a call into Jim Pace PERF Parts, when i get an answer i'll post it!

Red02LS1

I doubt they'd dyno closer to 350 RWHP with the limit of the cam. Doesn't the LS6 motor have a cam with .55x lift, and more duration as well?? I think my #'s are pretty high, considering I dyno'd with only 2,500 miles. Who knows, its a crap shoot, but I'd be pretty happy to find out that I got ls6 heads!

DaveSchott

iTrader: (5)

<img src="gr_sad.gif" border="0">

Never has, never will happen in THIS day and age.

2 reasons: 1. EPA certification. Cars are certified for EXACT drivetrain configurations. Not worth taking a chance on having your cert pulled on a vehicle line. 2. Inventory, staging, and assembly techniques are so sophisticated now only an idiot would attempt a substitution.

30 years ago mopar did that kind of funky stuff, ripping 6 pack intakes off 440+6 cars and slapping on 4 bbl manifolds at the factory. It doesn't work that way now, at least for components affecting emissions.

[ January 25, 2002: Message edited by: DaveSchott ]</p>

JC

I would say it's the LS6 block that gives the 01+ the extra hp.

I don't know what the technical name is but, the LS6 block has (bear with me) some type of holes machined in to let pressure under the piston escape faster.

Again, I don't know what they are called.

Ram Air Tony

iTrader: (2)

[quote]Originally posted by BigBake:
<strong>Well maybe not the 02's but a good possibility on the 01 heads....as the 01 heads dont have the upgrades of the 02 LS6 heads (sodium filled valves and the geometric differences that JohnB mentioned). If you think about it since they were scraping the old head design from the 01 heads to the new 02 heads it leaves a possibility. No one can seem to explain the high horsepower ratings of the 01's. Everyone thought it was because of the LS6 intake, but for the last year people have been putting on LS6 intakes on there 98 and up, and are not getting the returns like they thought. We also know the cam is a detuned compared to previuos years. We also know that the later 01 seem to be the cars with more power. So where did the extra HP come from? We are seeing cars turn 330 on the dynoes compared to the 290 of the 98-00. That is quite a bit of difference.</strong><hr></blockquote>

Bake is correct...the 01 LS6 heads would be the ones that would have had an overrun and would have gotten thrown on top of some LS1 motors.....I am having headers put on my 02 car as I type, I asked them to look at the exhaust port shape ..... my car put down 311 rwhp and 324 rwtq with 1000 miles on it (an 02 WS6) with lid only (also it is an AUTOMATIC <img src="gr_stretch.gif" border="0"> )

that is in 01 Z06 range figuring more drivetrain loss thru A4 (my stock Z06 put down 343,345) ..... so with LS6 intake, POSSIBLE LS6 heads I can see it (especially with a softer cam that LS6)

stay tuned cuz I will know on the exhaust port shape today

thanks

[ January 25, 2002: Message edited by: Ram Air Tony ]</p>

Ram Air Tony

iTrader: (2)

[quote]Originally posted by DaveSchott:
<strong> <img src="gr_sad.gif" border="0">

Never has, never will happen in THIS day and age.

2 reasons: 1. EPA certification. Cars are certified for EXACT drivetrain configurations. Not worth taking a chance on having your cert pulled on a vehicle line. 2. Inventory, staging, and assembly techniques are so sophisticated now only an idiot would attempt a substitution.

30 years ago mopar did that kind of funky stuff, ripping 6 pack intakes off 440+6 cars and slapping on 4 bbl manifolds at the factory. It doesn't work that way now, at least for components affecting emissions.

[ January 25, 2002: Message edited by: DaveSchott ]</strong><hr></blockquote>


the better flowing heads wouldnt affect emmissions negatively, in fact they would probably improve them due to a more complete combustion <img src="gr_grin.gif" border="0">

they make mid production improvements / changes constantly and we would never know (or would the EPA <img src="gr_stretch.gif" border="0"> )

R
A
T

LS1derfull

RAM AIR TONY, your right i know GM came out with a universal exhaust gasket that fits LS1 and LS6 heads in 2001. BTW my 2001 castings are #241. Confirmed LS6 #'s are(so far) #242 and #799. ANYONE ELSE HAVE #'s to compare?

2K1_4mula

Just talked with MTI, they were nice enough to check the casting numbers on any LS6 heads that were in their shop while I waited on the phone....

The only LS6 head casting they could verify is #243

By the way, they said they have NEVER seen an LS6 head on any of their camaro/firebirds from the factory. That is discouraging, but not enough for me to give up hope. I too have the #241 castings.

BigBake

I do not rule out anything anymore when it comes to 01 motors. We said the exact thing about LS6 blocks being in the cars, There is no way they would put one in, guess what they did. G.M. saved themselves money by having just one block. So why would they not continue the savings. As far as emmisions, those heads have already been certified on the same engine. The only differenc between a 01 LS1 and LS6 is a cam and PCM tuning. I know this has been brought up, but people blasted G.M. High Tech perfromance for releasing that article stating "A LS6 in F-body near you soon!" Well I think it was true, it is definitely partially true as far as the block and intake. I think there is credible evidence out there that late 01's and 02's, are probably running complete LS6 motors (minus cam).

BigBake

[quote]Originally posted by JC:
<strong>I would say it's the LS6 block that gives the 01+ the extra hp.

I don't know what the technical name is but, the LS6 block has (bear with me) some type of holes machined in to let pressure under the piston escape faster.

Again, I don't know what they are called.</strong><hr></blockquote>

You are talking about the breathing bays, this prevents the oil from being whipped up, and does not produce horsepower. But it does effect your RPM. They could run higher RPM's on the LS6, and they do.

Red02LS1

So the late model 2001's and all 2002's have the ls6 block?