G5X3 or MS3
Ms3/prc stg 2.5 5.3's 
i am runnong the ms3 /prc 5.3 stg 2.5 with stock gaskets with no issues.all bolt ons ls6 int/p&p tb/3" x into flows & trn dwns.430rwh/380rwtq.3 pwr tours drive alot on the street but i love big nasty sounding cams.4:11's all in ,72ss camaro 25mpg hwy.11.53 1/4 at 118mph....7.31 1/8.addiction has taken over ...again afr 205's with pat g spec cam coming soon. 
If those heads were not setup for the MS3 when they were ordered, they are not going to clear without flycutting. If the G5X3 is up there in duration and has aggressive lobes like the MS3, then it's not going to clear either.
Also, the camshaft does not have SCR as stated in post#2. The long-block determines the SCR, the camshaft and its valve events (intake) determine the DCR.
Call, PM, or email us if we can help
Also, the camshaft does not have SCR as stated in post#2. The long-block determines the SCR, the camshaft and its valve events (intake) determine the DCR.
Call, PM, or email us if we can help
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Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
