241 Heads

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Apr 13, 2009 | 11:18 AM

#21

Lt1Porsche

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From: Midlothian, Virginia

Im just going to install it straight up. So should I leave the heads at stock height or is milling them .030 okay?

Apr 15, 2009 | 09:49 PM

#22

MasterMindMotorsport

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From: S. Michigan

can anyone link the home porting advice thread ? or how to thread ? I have ported heads before but never LSx ones. Just a bunch of SBF's.

Apr 16, 2009 | 12:58 PM

#23

hammertime

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From: Smithton, IL

Here is the best info I could find on 3 pages of my search for "port" "porting" in the Gen III Internal Engine Forum. Some threads more detailed than others, but all have some relevant information.

Need Info on Hand Porting LS-6 heads
Flow results on my home ported heads
port 241s or just buy some 2.5s snd sell mine?
home porting heads questions
can these barely ported 241 heads make any power?
head porting questions
ls1 head porting
Home porting pics
LS1 Heads
Home 241 head Porting

Last edited by hammertime; Sep 28, 2010 at 07:37 AM. Reason: Added a new link: Home 241 head Porting

Apr 16, 2009 | 01:09 PM

#24

99Ls1fever

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From: Eaton, Colorado

Quote:

Originally Posted by Shawn MacAnanny

I honestly wouldnt even waste the money unless you have lost a head gasket. The most you can probably bump your dynamic compression ratio is something like .010" just guessing with the stock cam but just that difference can be made up by running a cometec .040" head gasket instead of the stock GM .054" head gasket to raise compression. See there is static compression which is the compression that your pistons and heads make (i.e 10.1:1 stock with 67ccs) and the dynamic compression which is of the engine running which i believe ideal dynamic compression is something like 8.5:1 or something i think stock is like 8.4:1 i THINK. I know my dynamic compression is something like 7.9:1. the longer duration keeps the valves open longer thuse bleeding off some of the compression

You dont want to run a higher dynamic compression with the nitrous as you will already have to retard timing and retarding timing even further could causeyou to lose power or create unnecessary knock.

Why do a 'small' ammount of port work? Are you doing this yourself?

+1 I got in the same argument with my mechanic and by the time I figured out how much it would cost to port the heads get a valve job and stay at the same compression, while still having to swap out springs and pay for those. He talked me into buying PRC 2.5 Heads for with in 100 dollars of having to do all of that work I got a New GM casting head and springs 2.02 valves and fully bolt on ready setup. Plus if you want to, get there lower CC head and boost your compression to 10.75 to 1. I was in the same spot and sold the 243's for 400 bucks and I got new heads that flow well for around 600 bucks. Good Deal IMO

Apr 16, 2009 | 06:54 PM

#25

hammertime

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From: Smithton, IL

I assume you meant that you spent $600 more to get a PRC 2.5 head (total of $1000). Are you referring to the 5.3 heads or LS6? 5.3's are listed at $1134.99 at present, so I could see you getting them for about $1000 some time ago. LS6 heads are $1424.99 right now, quite a bit more.

Texas Speed Cylinder Heads

No flame intended, as I bet that setup

and gets!

Apr 16, 2009 | 07:07 PM

#26

99Ls1fever

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From: Eaton, Colorado

Quote:

Originally Posted by hammertime

and gets!

Yea 600 more on the PRC's . And, yea it was the PRC 5.3 heads. I actually got the bigger combustion chambers on them to keep compression down for future boost applications though. Where he if he so choses can get the smaller combustion chambers to raise his compression

After you start her up. She does get to the point quick. She is Set up to go though

Apr 24, 2009 | 07:13 PM

#27

hammertime

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From: Smithton, IL

After doing the research for post #23 above, and coming across a great deal on a setup of take off 241 heads, I've changed my tune, and I'm going to see what I can do to improve on what I have without breaking the bank, or a stock 10-bolt. Let's hope I can prove myself wrong, along with other critics...

<hijack off>

and to Lt1Porsche, the OP, best of luck. Please report your results!

Oct 29, 2010 | 03:57 PM

#28

LS6

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From: Cherry Hill, New Jersey State

Quote:

Originally Posted by hammertime

You got the best links for hand porting

Oct 29, 2010 | 09:15 PM

#29

hammertime

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From: Smithton, IL

Quote:

Originally Posted by LS6

You got the best links for hand porting

Thanks! Hopefully one day I will get off my duff and add some info of my own. Still have two sets of heads that are untouched in my garage (three counting the stockers still on the car).