What is the diff.

**1 TRANS AM** · 07-09-2008, 05:13 PM

I have a set of heads off my 99TA. The casting is 853. What is the difference in these and the 241s?

**1 TRANS AM** · 07-11-2008, 01:04 PM

32 views and NO ONE KNOWS.

**Hot Black Trans-Am** · 07-11-2008, 06:55 PM

The 853 doesn't flow as well as the 241. The 241's were on 01 & 02's.

**blackhawk01** · 07-11-2008, 06:58 PM

806 - 98 heads (perimeter head bolt pattern)
853 - 99-00 heads (newer center bolt valve cover design)
241 - 01-02 heads ("")

243 - Z06 heads

**jsteele90** · 12-05-2008, 07:33 PM

my 2000 came with 241 heads. it has 243s now!!!!1

**c5z28** · 12-05-2008, 09:03 PM

different casting 241's should be slightly smoother, not enough for a head swap though.

**mark21742** · 12-06-2008, 01:04 AM

Originally Posted by blackhawk01

806 - 98 heads (perimeter head bolt pattern)
853 - 99-00 heads (newer center bolt valve cover design)
241 - 01-02 heads ("")

243 - Z06 heads

04 goats have the 241's also

**mark21742** · 12-06-2008, 01:10 AM

any chance of getting a sticky on oem heads, specs, advantages/disadvantages, and posibilities of porting?
I don't know if its too much to ask of the mods, but I know it would really help a lot of us out.
I've learned more than I ever thought I could here on the site, you all do a great job!