Ls6 vs Ls2 heads?
Ls6 vs Ls2 heads? sorry guys Ive searched and it seems I cant really get a straight answer on the differences I know they Both use the 243 heads casting but the ls6 has the lighter valves but what Im really concerned with it is
Do they have the same size combustion chambers and can the Ls6 heads with there slightly longer valves because of the z06 cams smaller base circle be used with a tr224 came or with I need custom pushrods?
Do they have the same size combustion chambers and can the Ls6 heads with there slightly longer valves because of the z06 cams smaller base circle be used with a tr224 came or with I need custom pushrods?
If they're both the same casting number (243)... the combustion chamber would be the same.
IDK about your cam question though. I was under the impression the valves are the same length but the push rods are a different length.
IDK about your cam question though. I was under the impression the valves are the same length but the push rods are a different length.
The LS6 heads have valves that are 0.050" longer than standard LS1 valves so you theoretically would need to run 7.350" pushrods. It's always best to measure pushrod length and know that you are using the proper length than to guess at it though. It's not really custom length as most manufactures sell pushrods in 0.025" increments, and if you upgrade the cam and springs you should be running a good set of pushrods anyway.
The 243 head is the 01+ LS6/LS2 head.
It has a smaller 64.45cc chamber for more compression (10.5 CR on LS6), 210cc intake runners, and 75cc D-shaped exhaust ports.
All three came with 2.00" intake valves, and 1.55" exhaust valves.
Of the three, the 243 (Z06) head is the most desirable for flow, and is the most popular base for further porting/modifying. Not many people mess with porting LS1 heads anymore.
And FYI for the ones you didn't mention...
5.3 truck heads (casting #862 and 706) are also a very popular base casting for porting/modifying, due to their even smaller (61.15cc) chamber size which raises compression when used on a LS1/6 engine..
6.0 truck heads (casting #317) are popular heads with the forced induction crowd, as they are basically the same as 243 heads, but with larger 71.06cc chamber size, which lowers compression when used on a LS1/6 engine.
It has a smaller 64.45cc chamber for more compression (10.5 CR on LS6), 210cc intake runners, and 75cc D-shaped exhaust ports.
All three came with 2.00" intake valves, and 1.55" exhaust valves.
Of the three, the 243 (Z06) head is the most desirable for flow, and is the most popular base for further porting/modifying. Not many people mess with porting LS1 heads anymore.
And FYI for the ones you didn't mention...
5.3 truck heads (casting #862 and 706) are also a very popular base casting for porting/modifying, due to their even smaller (61.15cc) chamber size which raises compression when used on a LS1/6 engine..
6.0 truck heads (casting #317) are popular heads with the forced induction crowd, as they are basically the same as 243 heads, but with larger 71.06cc chamber size, which lowers compression when used on a LS1/6 engine.
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hmmm now what if you dont wanna change the CR? is it better to just take the ls1 head p&p it and re do the valve train? keeping in mind here my car is a DD, and i dont really have much of a desire to make more than @400rwhp.
i have no prob making over 400rw with 2.02 valve, vj stock 243's
I would not EVER IMO, waste time porting a LS1 Head. I would just find 243 heads on ebay or buy 243 heads from a aftermarket company out there. LS1 Heads flow terriable and there potintial is very low. I like a few heads out there. Of coarse AFR and Trick Flow every one and there mom will tell you to buy. Well IMO I am not going to waste 2300 dollars on heads. I would look into a few different aftermarket companies. I have always had good luck with texas speed and their products. I like the PRC 2.5 Heads in LS6 and the 5.3's. I also if you are in to newer technology go with TSP LS3 Heads which I am seriously looking in to as we speak just for the simply fact they out flow 90% of the current heads out there by 40-45 cfm's. Find a good cam, doesnt have to be big and you have a very succesful build with not a huge amount of money. I am looking into the LS3 heads for my daily driver, and just a mild to meduim camshaft with a stock or aftermarket LS3 Intake. I just think it would be a fun build and cool to have the new technology under the hood. Plus very good gains to be found with the 350-360 cfm flowing heads.
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Verdad Gallardo PRC 2.5 5.3 Heads I paid 1054 bucks for flow 312cfm. LS3 Heads from TSP 1,134 Bucks and flow 350-360 cfm. A big hp differance in flow for not that much money. Espically over your stock 853 heads. 50 hp differance probably.
Yeah Just Found that out the hard way 
Suck!!! Just got off the phone with TSP and they broke my heart and gave me the bad news. O well, they said they would do a nice job on my 408 conversion collecting dust in my garage though 
Suck!!! Just got off the phone with TSP and they broke my heart and gave me the bad news. O well, they said they would do a nice job on my 408 conversion collecting dust in my garage though 
Well it depends my Elliot Port Works 241 stage II(Ferrea 2.02/1.60 valves, Patriot Gold Dbl springs, Ti retainers, locks and locators, custom valve job) $1200 flow like TEA's stage 1 243's except you have to invert the 550 & 600 flow numbers and if I would have gone with his stage III they flow more like TEA's stage 2 243's it all depends on the budget, who is doing the work, and the hard wear that goes into the heads. Will 241's ever outflow 243's no. The ports, and chambers are way better than the 241's but again if the budget does not allow it and the person working on them know what they are doing its up to the individual. my .02
Last edited by 02*C5; Jul 20, 2009 at 03:13 PM.
Well it depends my Elliot Port Works 241 stage II(Ferrea 2.02/1.60 valves, Patriot Gold Dbl springs, Ti retainers, locks and locators, custom valve job) $1200 flow like TEA's stage 1 243's except you have to invert the 550 & 600 flow numbers and if I would have gone with his stage III they flow more like TEA's stage 2 243's it all depends on the budget, who is doing the work, and the hard wear that goes into the heads. Will 241's ever outflow 243's no. The ports, and chambers are way better than the 241's but again if the budget does not allow it and the person working on them know what they are doing its up to the individual. my .02
i went with the darts last time.
Stock 243's do not flow in the 300's, while the valve train is lighter in them I went with the Ferrea hollow/sodium filled valves, bought then separate from the ones supplied by Lloyd. I think that my set up is better than stock 243's.
Ok Ive already bought all the parts for my cam swap including 7.400 hardened pushrods So Ill have to send my pushrods back and get 7.350 inch one instead Or would it just be smarter to go with the ls2 heads that have the standard valves?
And Yes everyone they do make a LS3 Cylinder Head For Small Bore LS1's Mast Motorsports sells it. 1200 each
