243s worth it??
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Racer
Joined: Jul 2005
Posts: 329
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From: North Little Rock Arkansas
243s worth it??
I have found a good deal on a set of 243s for my 98 coupe I plan on going with a trex cam. How much gain difference would I see from them compared to my 241s thanks
Safety Car
Joined: Jul 2005
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From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
If you're going to change the cam them you're going to need to change the valve springs. If I were you I would buy the 243 heads. They flow much better than the 241 casting. You might want to look into finding an LS6 intake too.
Drifting
Joined: Jun 2008
Posts: 1,333
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From: cruising between USA and Canada... SAVE THE WAVE!
I've got a complete LS6 upper end (LIE: 799s w/z06 cam and LS6 IM) going in my '98 coupe soon and I'm looking to pick up a healthy 35 or so rwhp with a tune.
I'd spring a bit extra for some 243s vs the 799s for the added comfort the hollow valves give, but I couldn't find any for a "good deal" and picked up some mint 799s instead.
If you're looking at dirty cheap, don't even think twice. 243s are really good heads. How much hp exactly you'll pick up is anyone's guess... it really depends on who you want to believe
Safety Car
Joined: Sep 2004
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You'll see a bump in power over stock 241's but IMHO you'd be better off putting the money toward having your 241's ported. For about the same price you'll see much better gains.
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Safety Car
Joined: Jul 2005
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From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
I agree that a set of 241 heads cnc'd would flow better than as cast 243's. But a set of cnc'd 243's will be worth much more if you ever decide to sell the heads. If you're going to invest in cnc work then I would do it to a set of 243's.
Last edited by printmanjackson; Apr 21, 2010 at 12:02 PM.
Safety Car
Joined: Sep 2004
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50rwhp
Mine were hand ported by Mike Stark at http://www.cfmperformance.com/ to the tune of $550. My dyno is in my sig for what I'm putting down.
are you saying the cost of a set of used 243 heads is about the same as having a set cnc'd machined? The last time I checked a good cnc head job was @ a grand.
I agree that a set of 241 heads cnc'd would flow better than as cast 243's. But a set of cnc'd 243's will be worth much more if you ever decide to sell the heads. If you're going to invest in cnc work then I would do it to a set of 243's.
I agree that a set of 241 heads cnc'd would flow better than as cast 243's. But a set of cnc'd 243's will be worth much more if you ever decide to sell the heads. If you're going to invest in cnc work then I would do it to a set of 243's.
Racer
Joined: Feb 2008
Posts: 410
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From: Topeka KS
The 243's alone aren't worth a LOT more than your stockers (I would say maybe 20-25RWHP after tuning assuming the cam doesn't change). As mentioned the 243's are a better head if you're going to have them ported later. If I was going to have the heads off anyways I think I'd probably try and find some heads better than as-cast 243's just to prevent having to do it again when you're ready for more power further down the road. You'll definitely see some nice gains though since you're doing a T-rex at the same time. I wouldn't be surprised to see 410+ RWHP out of that combo with a stock intake.
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Team Owner
Joined: Sep 2003
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From: Raleigh / Rolesville NC
Just porting or making everything larger inside is not always a good idea. Proper porting is essential, as to how and where to do the porting
On my 243 heads all we did was to clean up some of the rough edges and casting marks. milled the heads so the chambers are ~ 61 mm Checked the valves and valve seals too assure those were in good shape. Replace the stock springs with comp 918s.
Just this little bit pick up quite a bit of flow.
I run a small cam 224/224 581/581 112+4.. HP and TQ is great. and seat of the pants acceleration is better then most.
On my 243 heads all we did was to clean up some of the rough edges and casting marks. milled the heads so the chambers are ~ 61 mm Checked the valves and valve seals too assure those were in good shape. Replace the stock springs with comp 918s.
Just this little bit pick up quite a bit of flow.
I run a small cam 224/224 581/581 112+4.. HP and TQ is great. and seat of the pants acceleration is better then most.
