241 heads

**Bad Co.** · 10-14-2009, 06:10 PM

how much of an upgrade is it from 853 to 241 heads?

**02Sweet** · 10-14-2009, 06:51 PM

Originally Posted by Bad Co.

how much of an upgrade is it from 853 to 241 heads?

Not worth the effort even if free

**c5z28** · 10-14-2009, 07:09 PM

Different casting. I remember something about the valves on 97-00 going bad, but not worth switching over for another stock head. If you got them for free and wanted to bump compression via milling then that's another story.

**Mean Green Z28** · 10-14-2009, 09:36 PM

wait, what? They're the same head! 853's were early castings and 241's replaced them (or something like that). Some 853's had perimeter and some had center bolts and the 853's had the annoying notch on the deck surface ... http://www.smokemup.com/tech/ls1.php ... that's the dimensions of them (look where it says "stock LS1 head"). Actually, my setup is a mutant of the two; one 853 and one 241 (porter messed up one 241 and only had a 853 lying around to replace it), and I just got the 853 notch filled and both heads machined last week.

Now if you were going for 243 heads, you'll be bumping up compression 'cos you're losing like 2-1/4 cc's.

**c5z28** · 10-14-2009, 10:42 PM

Originally Posted by That Guy 2-1

wait, what? They're the same head! 853's were early castings and 241's replaced them (or something like that). Some 853's had perimeter and some had center bolts and the 853's had the annoying notch on the deck surface ... http://www.smokemup.com/tech/ls1.php ... that's the dimensions of them (look where it says "stock LS1 head"). Actually, my setup is a mutant of the two; one 853 and one 241 (porter messed up one 241 and only had a 853 lying around to replace it), and I just got the 853 notch filled and both heads machined last week.

Now if you were going for 243 heads, you'll be bumping up compression 'cos you're losing like 2-1/4 cc's.

worded it wrong ,meant by aftermarket milling. And the 806 head was the predecessor to the 853 with the different valve cover bolts.

**Mean Green Z28** · 10-15-2009, 05:48 AM

Originally Posted by c5z28

worded it wrong ,meant by aftermarket milling. And the 806 head was the predecessor to the 853 with the different valve cover bolts.

well hope the OP gets the idea from what we've all said ..

**9T8W66** · 10-15-2009, 06:15 AM

Unless their ported or LS6 no stock LS1 head is going to show a power gain over another.

806 `97-98 (Perimeter bolt valvecover)
853 `99- early 2000
241 late 2000 -`04

**Bad Co.** · 10-15-2009, 05:24 PM

man that sucks. i was honestly told otherwise. Then whats so different from the 98-2000 ls1's than the 01-02 ls1 other than the intake and cam? i guess i got burned, i paid 250 for the heads cause i was told by ls1 "pros" and "mechanics" that 241's out flow the 853's. Thats why they have diff part #'s. by the way whats a op?

**c5z28** · 10-15-2009, 07:38 PM

Originally Posted by Bad Co.

man that sucks. i was honestly told otherwise. Then whats so different from the 98-2000 ls1's than the 01-02 ls1 other than the intake and cam? i guess i got burned, i paid 250 for the heads cause i was told by ls1 "pros" and "mechanics" that 241's out flow the 853's. Thats why they have diff part #'s. by the way whats a op?

original poster

Get your money back

**9T8W66** · 10-15-2009, 08:06 PM

Originally Posted by Bad Co.

man that sucks. i was honestly told otherwise. Then whats so different from the 98-2000 ls1's than the 01-02 ls1 other than the intake and cam? i guess i got burned, i paid 250 for the heads cause i was told by ls1 "pros" and "mechanics" that 241's out flow the 853's. Thats why they have diff part #'s. by the way whats a op?

It's been said a million times on here.

An LS1 is an LS1 and they all make approx 345-350 HP at the flywheel.

**Mean Green Z28** · 10-15-2009, 08:11 PM

Originally Posted by Bad Co.

man that sucks. i was honestly told otherwise. Then whats so different from the 98-2000 ls1's than the 01-02 ls1 other than the intake and cam? i guess i got burned, i paid 250 for the heads cause i was told by ls1 "pros" and "mechanics" that 241's out flow the 853's. Thats why they have diff part #'s. by the way whats a op?

you've got to shoot those people seriously. As shown in the above link, the LS6 heads (243) flow only marginally better but also have a smaller chamber to increase CR. In other words, unless you're porting etc., not worth swapping stock heads. Wait, it was already said a few times here .. lol