PRC 2.5 5.3s vs PRC 2.5 ls6 heads
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formerly twolow02fransen (2014-1-2)
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PRC 2.5 5.3s vs PRC 2.5 ls6 heads
im trying to decide between the two of them im goin to be putting these on a LQ4. id like to get around 11.1 compression with the stock MLS .040 head gaskets which means id have to mill them to around 59cc correct me if im wrong. but my main question is the two heads flow almost the same
5.3 flow 312 intake 223 exhaust @600
ls6 flow 316 intake 226 exhaust @600
and also i plan on running a TSP torqer V.3 cam or something in that range and this is goin in a RCSB 1500 2wd any help would be great.
5.3 flow 312 intake 223 exhaust @600
ls6 flow 316 intake 226 exhaust @600
and also i plan on running a TSP torqer V.3 cam or something in that range and this is goin in a RCSB 1500 2wd any help would be great.
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formerly twolow02fransen (2014-1-2)
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they told me id be better off with the 5.3s cause of the smaller combustion chambers it would boost up my compression but i plan on milling the heads to 59cc weather i get the ls6 heads or the 5.3 heads.
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The 5.3's have 220cc ports vs the LS6's having ~230cc ports. With the smaller ports, the power band will be alittle lower in the rpm range than with the LS6's. With a heavy truck, you'd be better off with the 5.3's. even if you'd be down maybe 10hp because power under the curve will be alittle better.
Jason
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formerly twolow02fransen (2014-1-2)
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The 5.3's have 220cc ports vs the LS6's having ~230cc ports. With the smaller ports, the power band will be alittle lower in the rpm range than with the LS6's. With a heavy truck, you'd be better off with the 5.3's. even if you'd be down maybe 10hp because power under the curve will be alittle better.
Jason
Jason
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i have the 5.3 heads @62cc chambers and used a .040 head gasket on my LS1, and i am making 11.1:1 compression. i dont know why you think you need to run 59cc chambers to get that much compression, unless you dont have flat top pistons. i went 5.3 cause they were 300 cheaper at the time, and i didnt have to mill them. i love them, and if i was gonna spend more then 1200 on a head, then i was gonna go big and get the AFR 210cc heads. the 5.3 heads will be perfect for you, the more milling will drop off airflow, and in the end they will flow just about the same. shorter runners will give you better torque down low as well
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The reason I want to mill them to 59cc Is cause i have a lq4 which has dished pistons. Id be somewhere around 10.5 with the 5.3s un milled and somewhere around 10.2 with the ls6 heads unmilled