??? LS1 Heads vs LS6 Heads ???

**midi_2001** · 02-21-2009, 03:50 AM

I have an opportunity to pick up a set of stock LS6 heads.

Will a set of LS6 (243) heads bolt directly on to my 2001 LS1 engine without any modifications?

Is so, what are the pros and cons from a performance standpoint?

Thanks.

(Oops...should be list under "External Engine".)

**9T8W66** · 02-21-2009, 04:02 AM

Direct bolt in and a nice powergain.
I would add headers and a cam at the same time.

**midi_2001** · 02-21-2009, 04:27 AM

Originally Posted by 9T8W66

Direct bolt in and a nice powergain.
I would add headers and a cam at the same time.

I've already got the exhaust and I was planning on just a cam swap and not messing with the heads when I ran across these.

My cam considerations 'were' either:
Vector Motorsports: 228/232 .588/.574 112LSA
or
Thunder Racing: 230/224 .575/.563 111LSA

But I believe these heads would open the door to other options.

**Wesman** · 02-21-2009, 08:18 AM

Originally Posted by 9T8W66

Direct bolt in and a nice powergain.
I would add headers and a cam at the same time.

Agreed.

An LS6 H/C swap will net you about a 50WHP gain without sacrificing any driveability or fuel economy, which is a huge benefit..

**midi_2001** · 02-21-2009, 09:42 AM

Well, I bought them and just picked them up. A guy locally had them on Craigs List as BO. Got them for $350. They're definitely 243's with the yellow springs. He said they only have 3k miles on them and they look like it as well.

**99TransAmSLP** · 02-21-2009, 09:53 AM

Hmmm I might have to try and find me some lol

**midi_2001** · 02-21-2009, 10:06 AM

**99TransAmSLP** · 02-21-2009, 10:50 AM

Nice looking lol

**UTVols98** · 02-21-2009, 11:15 AM

A cam and some work on the LS6 heads (port and mill) can give you a 80+ rwhp gain.

**midi_2001** · 02-21-2009, 11:21 AM

Originally Posted by UTVols98

A cam and some work on the LS6 heads (port and mill) can give you a 80+ rwhp gain.

What's the average cost for porting the heads?

**UTVols98** · 02-22-2009, 04:08 PM

I've seen 500 on up to 2k. Depends on who you send them to and how much port work you want. Tony Mamo's of AFR is probably the best known. It'll cost a little money for him to do it. TSP does it also.

**blackSS01** · 02-23-2009, 09:26 PM

You hit jack pot just like me. I picked up LS6 heads too about 3 days ago. Looking at your pictures, you have the Triangles by the plugs which I do to, it means about 5 - 7 rwhp more over normal LS6 heads due to different casting process. Do a search on it and you'll get lots of info on them.

**midi_2001** · 02-25-2009, 02:59 PM

Originally Posted by blackSS01

You hit jack pot just like me. I picked up LS6 heads too about 3 days ago. Looking at your pictures, you have the Triangles by the plugs which I do to, it means about 5 - 7 rwhp more over normal LS6 heads due to different casting process. Do a search on it and you'll get lots of info on them.

Where did you find all the info on them?

**c5z28** · 02-25-2009, 03:33 PM

350 for complete heads thats a deal. You could port the heads but that's extra money, if you want to keep cost down get an asa cam w/ a low lift so you can keep the springs and you should have over 400rwhp no problem. Or swap out springs and go big.

**midi_2001** · 02-25-2009, 03:53 PM

Originally Posted by c5z28

350 for complete heads thats a deal. You could port the heads but that's extra money, if you want to keep cost down get an asa cam w/ a low lift so you can keep the springs and you should have over 400rwhp no problem. Or swap out springs and go big.

If my setup was, 2001 LS1 (WS6) M6 with, SLP lid, ported TB, stock LS6 intake, unported LS6 heads (243's pic'd above), Kooks 1-3/4" LT's, Kooks ORY, Magnaflow CB and 3.73 gears, what cam would produce the most HP and torque without overkill?

And again, with the same setup but porting the 243 heads?

(Changing the springs to accomodate the cam is not a problem.)

**blackSS01** · 02-26-2009, 08:47 PM

Here's a secret: If you want the best heads for performance, make sure your heads have these small triangle marks below every spark plug hole. The marks are left by "chills" used during the casting process in GM's semi-permanent mold (SPM) tooling. Of the three casting facilities that make Gen III cylinder heads, two use SPM tooling, the other heads are sand-cast. The SPM tools produce heads with very smooth, consistent ports and chambers which consistently dyno at least 4 to 7 hp better than the sand-cast heads.

Thats from this website with pics

http://www.carcraft.com/techarticles...ads/index.html

**reds10406** · 02-27-2009, 03:14 AM

Just wanted to let you guys know I called Wegner Motorsports a few weeks ago, they will port and polish a set of ls6 heads with a valve job for $550

Mine are going there when I get some $$$

**Firebirdjones** · 02-27-2009, 04:24 AM

Originally Posted by blackSS01

Here's a secret: If you want the best heads for performance, make sure your heads have these small triangle marks below every spark plug hole. The marks are left by "chills" used during the casting process in GM's semi-permanent mold (SPM) tooling. Of the three casting facilities that make Gen III cylinder heads, two use SPM tooling, the other heads are sand-cast. The SPM tools produce heads with very smooth, consistent ports and chambers which consistently dyno at least 4 to 7 hp better than the sand-cast heads.

Thats from this website with pics

http://www.carcraft.com/techarticles...ads/index.html

Ya my stock 241 heads on my 02 SS have these so called triangular casting marks too. Wasn't just on the LS6 heads.

**Firebirdjones** · 02-27-2009, 04:27 AM

Originally Posted by c5z28

350 for complete heads thats a deal.

I discussed this with another member not too long ago. I've actually been seeing quite a few LS6 heads at local swap meets for this much money and even less. They are out there to be had for reasonable.
I bought a set for myself to stash away.

**R_Yates69@Hotmail.com** · 02-27-2009, 11:43 AM

I put LS6 H/C on my 99 Trans Am WS6. I also put pacesetter headers and the difference is unimaginable. I got a custom tune for TSP and my car idles perfect at about 900rpm and my gas mileage is still decent. 550km/tank highway