PRC 220cc 5.3L Stage 2.5 vs PRC LS6 Stage 2.5 Heads
#1
PRC 220cc 5.3L Stage 2.5 vs PRC LS6 Stage 2.5 Heads
which heads would be more ideal for a street/strip LS1 with this cam
LSR 231/239 ,614/.624 113 LSA
here are the flow numbers for the two heads, the 2.5 heads are $300 cheaper. Also the 5.3 heads have a higher compression ratio around 10.75:1
here is the link for both heads.
LS6 heads
http://www.texas-speed.com/shop/item...d=134&catid=20
5.3 heads
http://www.texas-speed.com/shop/item...id=84&catid=20
i will be using the PRC .675 springs due to the much higher spring rates. they are ideal for the high ramp rates of the LSL lobes.
Thanks for the help.
LSR 231/239 ,614/.624 113 LSA
here are the flow numbers for the two heads, the 2.5 heads are $300 cheaper. Also the 5.3 heads have a higher compression ratio around 10.75:1
here is the link for both heads.
LS6 heads
http://www.texas-speed.com/shop/item...d=134&catid=20
5.3 heads
http://www.texas-speed.com/shop/item...id=84&catid=20
i will be using the PRC .675 springs due to the much higher spring rates. they are ideal for the high ramp rates of the LSL lobes.
Thanks for the help.
#2
Id save the 300, go with the 5.3's. They look like there really close plus the 5.3's with up your compression. You can use the 300 on the rest of the parts you need for the swap.
#7
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First, thank you for the service you are doing for our country.
Next you are talking 3 to 4 cfm between the two heads which is pretty much splitting hairs. You will save money and gain a little power from the bump in compression going with the cheaper ones...
Once you get it all put together get some time off and haul ***** south on HWY101 it's the coolest road in America in my opinion!
Next you are talking 3 to 4 cfm between the two heads which is pretty much splitting hairs. You will save money and gain a little power from the bump in compression going with the cheaper ones...
Once you get it all put together get some time off and haul ***** south on HWY101 it's the coolest road in America in my opinion!
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#9
now if i get the 5.3 heads, what head gasket should i go with. the heads will put me at about 10.75:1, should i use stock head gaskets? i have heard good things about the .045 and .040 MLS head gaskets, and it would bump my compression ratio closer to 11:1. also the quench area would be smaller and makes it safer vs detonation. is it worth the extra $100 or so bucks for a high end head gasket with smaller thickness or should i just go with stock GM style ones?
#10
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Same question about the head gasket... Thicker or thinner?? And I'm spraying also.. Would that matter?? Im going with the 5.3s and I have ms3 cam... What specs should they be milled to and what gasket thickness??
#13
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i am in the same spot here, I just bought the ms3, and now can't decide which heads to go with, 5.3 or the 2.5 ls6? texas speed told me on the phoen the ls6 will outflow the 5.3's from idle all the way through the rpm range, I dont know what to go with, spend the extra 300? or save it for new tires after the build is done.....
#14
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Been running some TEA 5.3 heads for about 5 years now (intake side flows 316 cu. ft. @ .600 lift) milled down to 58 CC chambers and .040 Cometic head gaskets for a nice tight quench .. no problems running pump gas .. compression is probably 11.3 or 11.4 to 1. Great combo ... high compression is free HP and better throttle responce ... the money that you save on the 5.3 heads pay for the head gaskets... its a no brainer to say the least. Thanks for your service..
#15
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I like the 5.3 heads because they add the extra bump in compression which prolly offsets the slight decrease in flow, but they do have less PTV clearance. With that cam I'd have them back cut the valveseats to ensure plenty of clearance especially if you're planning on milling any.
#16
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yeah i'll be on the phone with texas speed again to help figure it out, with which would be best for the setup. i guess you could have the ls6 heads milled to increase compression, but then would you have to worry about ptv clearance?
#18
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Been running some TEA 5.3 heads for about 5 years now (intake side flows 316 cu. ft. @ .600 lift) milled down to 58 CC chambers and .040 Cometic head gaskets for a nice tight quench .. no problems running pump gas .. compression is probably 11.3 or 11.4 to 1. Great combo ... high compression is free HP and better throttle responce ... the money that you save on the 5.3 heads pay for the head gaskets... its a no brainer to say the least. Thanks for your service..
#19
Hey if you know somethings wrong with the kool-aid (and a quick search confirmed you did drink it), you better speak up a little louder. I got a pitcher of it waiting in my garage after my own research (cheaper and more positive feedback on the taste per dollar as compared to something like tea).
#20
I'd do the LS6 they'll make about 10rwhp more and they can be milled for compression for free. At the same size combustion chamber as the 5.3s, the LS6 heads will also have better PTV clearance.