Porting 241's???
TECH Senior Member
Joined: Feb 2009
Posts: 5,445
Likes: 4
as long as the porter knows ls heads.dose that include a valve job?a $400 set of 243s with a valve job will flow 270cfm with stock valves.it is the last inch of the intake port that matters.good bowl work helps.
amen. the right work will cost you though. i spent almost the price of some budget 243's just on bowl and valve job work alone.(stock runners)
Sure, 243 heads have smaller and more efficient combustion chambers, but that doesn't mean that good results cannot be achieved with 241 heads. To compare apples to apples, you would spend $350 - $400 to get the 243's, then approximately the same amount to port them through the same vendor.
For a little less you could do just the valve job and bowl blending on the 241's as suggested. You should get 70% to 80% of the gains of a fully ported head for about half the cost.
Do you have any A to B comparisons to show what you get for your $750? Flow numbers and dyno results are nice, but track results usually tell the truth.
For a little less you could do just the valve job and bowl blending on the 241's as suggested. You should get 70% to 80% of the gains of a fully ported head for about half the cost.
Do you have any A to B comparisons to show what you get for your $750? Flow numbers and dyno results are nice, but track results usually tell the truth.
its not just the chamber that makes them better, a little farther up and over you can get them to work better then ls1 casting.
dont be scarde to put some money into a 243/799 with somone that know what there doing, i've seen them break 500whp on stock shortblock /346 with a fast, and run low 10's even high 9's
dont be scarde to put some money into a 243/799 with somone that know what there doing, i've seen them break 500whp on stock shortblock /346 with a fast, and run low 10's even high 9's
The old 241's are often maligned online, but they certainly can make decent power. If the choice is between a properly done 241 and an as cast 243, the 241 should be better. At the same time, if you will spend the $ on a set of 243's AND proper work, they should retain the hp advantage they have over 241's. If you want mid 4XXrwhp sae then our 241's have certainly proven capable of that. There have been a few results posted on tech w/ the lower end of the spectrum being 420-440rwhp and the upper end around 470rwhp. IIRC, that is with cams from 205deg to 232deg or so. 
Full high end CNC work, CNC VJ, milling to any volume or valve location, assy. for your app, etc. is typically $995. We can also do a more budget oriented deal that fully CNC's the exh, touches up all flanges, CNC VJ, etc., but we forego the fully CNC'd intake port for CNCing the venturi/bowl area down to the top top of the guide & then blend that into the as cast runner. That is typically $795. For the $/value I typically lean towards fully porting the head.
We are currently in the process of re-organizing & selling off heads that are taking up space. There's probably 7-9 sets of 241's with various CNC programs cut into them that we intended to list in the FS section when we had time. Including castings, which will save the end user from spending $ on shipping heads here as well, we were thinking ~$1k/set. Shoot us an email if interested. Thanks for the kind words, guys.
-Phil
Full high end CNC work, CNC VJ, milling to any volume or valve location, assy. for your app, etc. is typically $995. We can also do a more budget oriented deal that fully CNC's the exh, touches up all flanges, CNC VJ, etc., but we forego the fully CNC'd intake port for CNCing the venturi/bowl area down to the top top of the guide & then blend that into the as cast runner. That is typically $795. For the $/value I typically lean towards fully porting the head.
We are currently in the process of re-organizing & selling off heads that are taking up space. There's probably 7-9 sets of 241's with various CNC programs cut into them that we intended to list in the FS section when we had time. Including castings, which will save the end user from spending $ on shipping heads here as well, we were thinking ~$1k/set. Shoot us an email if interested. Thanks for the kind words, guys.
-Phil
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We are currently in the process of re-organizing & selling off heads that are taking up space. There's probably 7-9 sets of 241's with various CNC programs cut into them that we intended to list in the FS section when we had time. Including castings, which will save the end user from spending $ on shipping heads here as well, we were thinking ~$1k/set. Shoot us an email if interested. Thanks for the kind words, guys.
-Phil
Staging Lane
Joined: Dec 2006
Posts: 65
Likes: 0
Why don't u get the free heads and do free diy porting and maybe mill them and or then up put bigger valves And port the intake. if u ruin the heads no big deal u r learning. And ur nnot out money just ur labor? Then if u like the results then u can get some used 243s and port them yourself.
Why don't u get the free heads and do free diy porting and maybe mill them and or then up put bigger valves And port the intake. if u ruin the heads no big deal u r learning. And ur nnot out money just ur labor? Then if u like the results then u can get some used 243s and port them yourself.
I estimate I got 20 HP out of my home ported 241's and a .040 mill. I dont have a direct comparison, but I had 407 HP cam only 230/232, and hit 430 with my heads and a 232/234 on a very hot day. The added compression is the big benefit, it really adds to the low end and the drivability.
I went from 12.0's to 11.7's with JPR stage 1 241 heads. JPR only did bowl and throat
work, no intake runner porting. The heads even had the rocker boss bump in the intake
runner and they only flowed 265 cfm. There's too much worry about getting 300+ cfm.
I dropped 3 tenths and gained over 3 mph with only 265 cfm. I guess thats why stock
243's are running so good since they flow about the same. I guess i gained about 30 rwhp with my heads. And i only ran a 216/220 cam. Track times are what count. CFM, and dyno numbers are for bragging rights. We don't race on dyno's or benches
work, no intake runner porting. The heads even had the rocker boss bump in the intake
runner and they only flowed 265 cfm. There's too much worry about getting 300+ cfm.
I dropped 3 tenths and gained over 3 mph with only 265 cfm. I guess thats why stock
243's are running so good since they flow about the same. I guess i gained about 30 rwhp with my heads. And i only ran a 216/220 cam. Track times are what count. CFM, and dyno numbers are for bragging rights. We don't race on dyno's or benches
I went from 12.0's to 11.7's with JPR stage 1 241 heads. JPR only did bowl and throat
work, no intake runner porting. The heads even had the rocker boss bump in the intake
runner and they only flowed 265 cfm. There's too much worry about getting 300+ cfm.
I dropped 3 tenths and gained over 3 mph with only 265 cfm. I guess thats why stock
243's are running so good since they flow about the same. I guess i gained about 30 rwhp with my heads. And i only ran a 216/220 cam. Track times are what count. CFM, and dyno numbers are for bragging rights. We don't race on dyno's or benches
work, no intake runner porting. The heads even had the rocker boss bump in the intake
runner and they only flowed 265 cfm. There's too much worry about getting 300+ cfm.
I dropped 3 tenths and gained over 3 mph with only 265 cfm. I guess thats why stock
243's are running so good since they flow about the same. I guess i gained about 30 rwhp with my heads. And i only ran a 216/220 cam. Track times are what count. CFM, and dyno numbers are for bragging rights. We don't race on dyno's or benches
A good valve job and bowl/throat blend work is worth around 30cfm from my research.... from any reputable LSx head porter on a 241 casting.