241 vs. 243
#2
TECH Enthusiast
iTrader: (6)
Join Date: Sep 2007
Location: Mo
Posts: 546
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Only difference in the 853s and 241s is the casting methods. 243s have bigger intake runners and smaller chambers which will bump up your compression and flow better. As far as hp just a guess stock 243s over 853s maybe 20hp.
Last edited by BaddBird; 12-16-2009 at 09:14 AM.
#4
FormerVendor
iTrader: (18)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I wouldn't waste your money going to a 241. However, the 243's will definitely gain you some power. I'm guessing in the 15-20 range on a set of unported heads. You can also, shoot the heads to us and have them ported before you put them on if you have a little extra cash. We can CNC port the heads and CNC valvejob them along with a light mill to square up the deck surface. You would be looking at $650 if you wanted to do it. Let us know if we can help!
Jon
Jon
#5
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I wouldn't waste your money going to a 241. However, the 243's will definitely gain you some power. I'm guessing in the 15-20 range on a set of unported heads. You can also, shoot the heads to us and have them ported before you put them on if you have a little extra cash. We can CNC port the heads and CNC valvejob them along with a light mill to square up the deck surface. You would be looking at $650 if you wanted to do it. Let us know if we can help!
Jon
Jon
#6
Trending Topics
#10
Staging Lane
iTrader: (1)
Join Date: Sep 2007
Location: Moody AFB Valdosta GA
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Hey,,,,, you tell me. I have been askin that SAME question for the last 7 months. the only thing i can figure is the original owner of the car fluffed his dyno numbers. i was running a G5X3 236/242 .600/.600 at 112, then i switched to a comp 232/236 .595/.601 at 114 with the 243's. off the spray i did 404 on 503. It ran a "reported" 402 off 502 on before.....
#13
TECH Enthusiast
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I just did this swap and the difference is considerable, the car chirps third much harder, and pulls away from my buddys 370z quickly.. were as before it slowly walked away.
I won't know the quarter mile difference until this summer.
I won't know the quarter mile difference until this summer.
#14
TECH Regular
iTrader: (1)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I wouldn't waste your money going to a 241. However, the 243's will definitely gain you some power. I'm guessing in the 15-20 range on a set of unported heads. You can also, shoot the heads to us and have them ported before you put them on if you have a little extra cash. We can CNC port the heads and CNC valvejob them along with a light mill to square up the deck surface. You would be looking at $650 if you wanted to do it. Let us know if we can help!
Jon
Jon
#20
Launching!
iTrader: (15)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
not sure if thats the case thats all we had back in the day. old castings ported right r hard to beat. just look at the 5.3 head tsp offers compared to the ls6. flow #s r not far off. An ls head should have the same potential a 5.3 head has...
Last edited by LTX355; 12-18-2009 at 12:24 PM.