Notices
GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

Which head for "iron" l33?

Thread Tools
 
Search this Thread
 
Old 10-21-2009, 08:00 PM
  #1  
TECH Resident
Thread Starter
iTrader: (18)
 
kazfan30's Avatar
 
Join Date: Mar 2005
Location: Hattiesburg, Mississippi
Posts: 772
Likes: 0
Received 0 Likes on 0 Posts
Default Which head for "iron" l33?

I am building a true budget motor for now to replace the tired 4.8. I have a built 5.3 on the stand with a set of 4.8 pistons i had laying around and a comp 212/218 522/529 114 cam i had as well. I realize that the L33 had 243/799 heads and around 9.9:1 CR, but i dont have the cash for 243s right now so i have a choice of cleanin up a set of 241's or the stock 706's. Either one will be slightly surfaced and the runners and bowls mildly ported and smoothed. Any ideas on which to go with, or what kind of CR i would be looking at? Future plans are either a Maggie or a small shot... Thanks alot
Old 10-21-2009, 08:55 PM
  #2  
2nd fastest 5.3 ECSB
iTrader: (14)
 
trever1t's Avatar
 
Join Date: Oct 2005
Location: NorCal
Posts: 26,690
Likes: 0
Received 1 Like on 1 Post
Default

what's the chamber size of the 241's, I forget but putting the stock heads on there would bump CR up too much.
Old 10-21-2009, 10:02 PM
  #3  
TECH Addict
iTrader: (4)
 
SweetS10V8's Avatar
 
Join Date: Jun 2004
Location: Michigan
Posts: 2,584
Likes: 0
Received 0 Likes on 0 Posts
Default

I dont think 4.8L pistons will work in a 5.3L. The 4.8L has a different stroke and rod length. The odds of the resulting required compression height on both pistons being the same on both a 5.3l and a 4.8L are remote.... Although I could be 100% wrong.
Old 10-21-2009, 10:19 PM
  #4  
TECH Resident
Thread Starter
iTrader: (18)
 
kazfan30's Avatar
 
Join Date: Mar 2005
Location: Hattiesburg, Mississippi
Posts: 772
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by trever1t
what's the chamber size of the 241's, I forget but putting the stock heads on there would bump CR up too much.
I believe the 241s have 66 cc chambers which is only 1-1.5 cc more than the 799/243. I would have guessed my CR to be a tad less than 9.9 maybe around 9.5-9.7ish range. But if i keep the 706's i would be close to if not more than 11.1:1. I am leaning toward the 241's due to more boost friendly CR and a larger valve as compared to the 706...and with a "low lift cam" i would see this assisting air flow at the lower lift.....? In other words since the runner is identical on 241 and 706 ill maintain "good" torque and with the larger valve i should surely let more air in at same given lift.



Oh and yes 4.8 pistons will work on a 5.3...as proven in the L33 HO
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
lsxmalibu
GM Parts Classifieds
4
09-09-2015 11:08 PM
03regcab sierra
INTERNAL ENGINE MODIFICATIONS
2
09-09-2015 02:02 PM
axekick
WTB (Wanted To Buy)
5
09-07-2015 07:01 PM
jaypowe11520
GM Engine & Exhaust Performance
10
07-29-2015 07:59 PM
sauldgold
GM Engine & Exhaust Performance
3
07-23-2015 02:15 PM



Quick Reply: Which head for "iron" l33?



All times are GMT -5. The time now is 08:02 AM.