porting question on 241 heads
Limitations I'm not for sure on; but I was told by the man that did some work for me that it does make a difference if you have an A4 or a 6 speed. So that could be one thing you might want to factor in as well. He said the auto needed to be ported for tq differently than the manual. I don't know for sure but I know that he does alot of local F-bodies. Hope this may help out some. I know it was'nt the original ? but I felt it might be helpful.
On The Tree
Joined: Sep 2004
Posts: 188
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From: Houston, TX
As inexpensive as the 243 heads are now there's no way I'd waste my time and money on 241's. All you'll end up with in the end is an expensive set of 241's that don't run as fast as you'd like and have little resale value.
Originally Posted by Greg Good
As inexpensive as the 243 heads are now there's no way I'd waste my time and money on 241's. All you'll end up with in the end is an expensive set of 241's that don't run as fast as you'd like and have little resale value.
Can you please substantiate the claim you made (with any resale arguments pushed aside)?
Ben T.
Last edited by Studytime; Apr 24, 2007 at 12:28 AM.
Originally Posted by 1EVLBRD
what are the porting limitations on stock 241 heads?
...but that's only if you're porting for a M6.
Ben T.
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Ported a set of 241's myself I got off eBay. Focused the porting on reshaping the valve stem for good flow passed it onto the back of the valve. Also removed the rocker-arm bolt boss the protrudes into the port. Also port matched the head to the BBK intake. Finally, cut .020 at the machine shop to bring up the compression a bit. Made 412/378 with a TSP T v.2 cam. I am currently swapping this head cam combo onto a 408. I was very happy for my performance per dollar. Heads: $150, self-ported: free, porting kit - $50, 3-angle valve job, cut .020, assembly: $160, total: $360. Gain: probably 40-60 hp (am I being optimistic here???)
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Originally Posted by 5ltrBetr
Gain: probably 40-60 hp (am I being optimistic here???)
Ben T.
Originally Posted by GuitsBoy
50 or 60 HP gain out of the heads AND the cam maybe. I have a set of home ported heads, milled .040 and this gained me 25 - 30 HP over a cam only Torquer2 car.
Ben T.
Originally Posted by Studytime
Keep in mind that guitsboy also has a lot more compression with was some of the gain. His port work is responsible for the rest.
Ben T.
Ben T.
Yea, I figured I was dreaming! Anyway, I know the aftermarket heads might flow better and make a little more power, but if I can get 280 cfm at .600 for $360, I'll have a hard time paying $2500 for 300 cfm. That leaves me with $2100 for one hell of a spray!
280 CFM is reaching too. I think 260 to 270 is a more realistic outcome for the home porter. Still, that dosnt mean you wont see worthwhile gains. And besides as it was mentioned, porting is only part of the equation. Milling for compression, thinner gasket for a tighter quench, and proper cam choice will help you get more out of your heads.
I thought my first LS1 heads were WAY above average (at the time ) and they did an amazing 255 cfm. 
Experience (and a lot of it) goes a long way. With none 280 cfm (at .600") is a stretch. I couldn't get in the 280s until a year and half of practice. Looking back, it's not that hard, but beginning to see it is the hard part. If you're home porting, do what Guitsboy did. Do your best and make it as consistant as you can and then mill the crap out of them and flycut.
Ben T.
) and they did an amazing 255 cfm. Experience (and a lot of it) goes a long way. With none 280 cfm (at .600") is a stretch. I couldn't get in the 280s until a year and half of practice. Looking back, it's not that hard, but beginning to see it is the hard part. If you're home porting, do what Guitsboy did. Do your best and make it as consistant as you can and then mill the crap out of them and flycut.
Ben T.
