i am noticing different numbers for head castings from 98-02, i know i have 241's and i have heard people saying that the 02 241's are the best, i would like to know some differences between the different heads and why '02 241's are so good, thanks for the help!

 

They flow good, but the 243's flow the best.

 

i guess no one knows anything else about them, would like to know more, why?, how?, any flow #'s, any dimensions or characteristics? why 02's are better than previous 241's?

 

my 853's are real good, but they are ported. People knocked on the old 806 heads the 98's because they were cast differnt and the air was getting caught up. They all flow pretty close, but stock for stock 243 heads are king.

 

i know about 243's i was wondering about the others versus my 241's

 

bump^ for the night

 

anyone know anything about what i asked?

 

anyone???????

 

All castings aside from the 243's will flow similar when ported. Unported, the '97/'98 sand cast heads flow less than the '99 and up PM (permanent mold) castings do, but I doubt the difference is that pronounced. 243 heads flow better because they have a larger intake port that is revised slightly to increase the flow. Other than that, pretty much all LS1 heads flow alike. Also, as a side note - In my opinion it is completely worthless to swap stock castings for other stock castings, even from 806's to 243's because the gain isn't worth the amount of work that needs to be done. If you want to swap heads, install ported heads.

 

thank you, finally getting some answers, so i guess 241's aren't worth much over the others, i guess someone told me a bunch of crap

 

I dont think its worth putting 243's on a car w/o them being ported as well. Not a big enough gain.

 

Yeah all the crap going around about 806 heads being inferior was really BS IMO. Thanks LS1Formulation you cleared the air for Me as well. I knew there were differences but nothing to substantiat a noticeable gain

 

Take what you hear on the internet with a grain of salt anyway. 99% of people here have never flowed 2 stock unported different casting heads on the same flow bench back to back. People mostly just repeat what they herad from someone else here.

 

I agree 100%

 

i have a LS1 and im afraid i gonna tear up my rear end what do you recommend I go with?...and how much do u think ill spend?.....thanks

 

.........

 

 

Well there it is,.....find a good tuner and make sure he reads all this "stuff" and keeps up with all the different "jobs" and their results.

 

this is some information I have been dragging around with me for like 3+ years (when the LS2 heads first came out). I copied from a post (grain of salt?)...don't know if it was this forum or the old LS1 (before it died and was resurrected). The info seems reasonable, considering that some designs also used different valve sizes.

5.7l Head Flows (stock)
LS1 5.7l
Intake =0.550" @ 223.2cfm
Exhaust=0.550" @ 175.6cfm

LS1 5.3l
Intake =0.550" @ 221.5cfm
Exhaust=0.550" @ 168.1cfm

LS1 6.0l
Intake =0.550" @ 238.2cfm
Exhaust=0.550" @ 172.9cfm

LS6 5.7l
Intake =0.550" @ 256.0cfm
Exhaust=0.550" @ 180.0cfm

 

or attempted to!