Differences between 241 and 243 stamped heads?
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Joined: Aug 2005
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From: Tampa, FL
Differences between 241 and 243 stamped heads? Just wondering if there is a difference. I saw an older z06 w/ 241's then my wifes 01 z had 243's. Thanks.
EDIT: the search button kept giving me a "NET server error" so I couldn't search.
EDIT: the search button kept giving me a "NET server error" so I couldn't search.
241 are 2001-2002 LS1 heads. Chamber size was 68cc.
243 are 2001 (I thought) and newer LS6 heads, as well as LS2 heads. Typically the LS6 heads had sodium filled light weight valves and 64cc chambers. LS2 had standard valves and 64cc chambers.
The 243 heads flow better then 241 head when stock. If they are modified (ported) then it is a different scenario.
243 are 2001 (I thought) and newer LS6 heads, as well as LS2 heads. Typically the LS6 heads had sodium filled light weight valves and 64cc chambers. LS2 had standard valves and 64cc chambers.
The 243 heads flow better then 241 head when stock. If they are modified (ported) then it is a different scenario.
you didn't see 241 heads on a c5 z06, as the c5 z06 only came with the ls6 engine.
241 heads came on mid-00 through the 02 fbody cars. if a 2000 car got 241 heads, it also got the ferrul-less (stronger) rod bolts.
243 heads have a smaller combustion chamber (but offer the same ptv) and flow better than the 241 heads. they also have lighter valves. they are worth roughly 15whp on an m6 stock 10 bolt setup.
241 heads came on mid-00 through the 02 fbody cars. if a 2000 car got 241 heads, it also got the ferrul-less (stronger) rod bolts.
243 heads have a smaller combustion chamber (but offer the same ptv) and flow better than the 241 heads. they also have lighter valves. they are worth roughly 15whp on an m6 stock 10 bolt setup.
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Joined: Mar 2006
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From: Rolesville, NC
and there are two different GM 243 heads.
"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. "
Source: http://www.carcraft.com/techarticles...ads/index.html
"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. "
Source: http://www.carcraft.com/techarticles...ads/index.html
here is the most useful info i have found to date!!!
http://web.camaross.com/forums/showthread.php?t=410492
http://web.camaross.com/forums/showthread.php?t=410492
and there are two different GM 243 heads.
"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. "
Source: http://www.carcraft.com/techarticles...ads/index.html
"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. "
Source: http://www.carcraft.com/techarticles...ads/index.html
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Yea, as far as factory castings, they are the best. A few GM tech books mention them too. But that HP diff is up there with valve train weight. Sodium filled valves and Ti retainers vs all Stainless etc etc.
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Verdad Gallardo TECH Regular
Joined: Mar 2006
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From: Rolesville, NC
But also say that Sodium filled exhaust Valves, Titanium intake valves and Ti retainers are just more expesive then Stainless steel and no performance difference too.
I thought light wt valve trains were for above 6200 rpms ?
Some builders say there is not a difference in these castings.
But also say that Sodium filled exhaust Valves, Titanium intake valves and Ti retainers are just more expesive then Stainless steel and no performance difference too.
I thought light wt valve trains were for above 6200 rpms ?
But also say that Sodium filled exhaust Valves, Titanium intake valves and Ti retainers are just more expesive then Stainless steel and no performance difference too.
I thought light wt valve trains were for above 6200 rpms ?
Will it make or break a engine combo, no.
I attributed the potential power increase to a valve train weight theroy and that it is important to get the best out of it, but if you got your hands on a set of 243's w/o the Triangle in the casting, it isnt the end of the world.
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From: 415 Northern CA
If you thought you had seen a Z06 with 241 cylinder head's, it was most likely the fixed roof coupe version of the corvette. The FRC is same body style as the Z06 with no hatch, but retain's an LS1. Kind of vague when you talk about your wife's Z. State whether it's a Z28 or Z06.
Thread Starter
11 Second Club
Joined: Aug 2005
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From: Tampa, FL
If you thought you had seen a Z06 with 241 cylinder head's, it was most likely the fixed roof coupe version of the corvette. The FRC is same body style as the Z06 with no hatch, but retain's an LS1. Kind of vague when you talk about your wife's Z. State whether it's a Z28 or Z06.
-Mark
