You won't find many off-the-shelf small cams with a big lope, so you may want to go with a custom grind. If so, go here:
Comp Cams Custom-Grind LS1 Camshaft
and do this:
Intake: 212 .558" XE
Exhaust 224 .568" XE
LSA: 110
ICL: 110
This will give you a healthy lope and perform well in your truck. Comp doesn't charge more for a custom grind and only takes a few days to grind and ship directly to you. I would target the stall in the 2800-3200 range.
Won't a smaller LSA help the powerband get up sooner? i.e. a 112 will make power sooner than a 116 with the same duration and lift?
Unless you have a turbo you want to build boost or N20 that benefits from the higher peak cylinder pressure of the wider split. That 212/224 on a 110 will have a lope for sure.
This will be the case if the smaller LSA results in the intake valve opening and closing sooner. If the smaller LSA is a result of the exhaust valve opening and closing later, then no, the powerband won't get up sooner. In fact, you would lose low-end power since the increased overlap would bleed off cylinder pressure in the lower RPM range. This is why cam manufacturers recommend higher static compression on some of their grinds.
Generally speaking, for two cams with the same I/E durations, the cam with the narrower LSA will will max out a little sooner and be a little peakier than a cam with a wider LSA, which will wind a little higher and have a broader torque curve. This assumes that the LSA differences were caused by moving both intake and exhaust centerlines the same.
2000 ECSB 6.0L
TORQUER V2 CAM ● COMP 918's ● 7.4 HARDENED PUSHRODS ● K&N SERIES 77 CAI ● 80mm BBK ●PACESETTER LT HEADERS AND 3'' ORY ● SUPER 40 FLOW ● 3000 STALL ● 4.10s ● BUILT 80e ● VORTEC PERFORMANCE TUNE ● MSD 8.5mm PLUG WIRES● ELEC. CUTOUT ● UD & ALT PULLEYS ● FLEX-A-LITE E-FANS ● 22" CENTERLINE STINGRAY III's ● LUND FIBERGLASS TONNEAU ● 2" LEVELING SHACKLES ● 12K HID LOWS & FOGS ● LEDs ● DEBADGED ● WHITE-FACED ESCALADE GAUGES ● KICKER 450.1 ● 2-CVR 10's ● DS60's ● K693's
What do you guys think about this set up? MS4 cam(239/242 .649"/.609 111 LSA) and 3500 stall
Go big or go home right?
Last edited by Ghost04; 11-04-2008 at 03:09 AM.
Not even close to what you need....Over camming a heavy truck with a stock compression 4.8 would get very old quick!!.....don't let the temptation of "going big or go home" be the deciding factor for chosing a cam... look around at the FTL and see what some of the other 4.8's are running..and take in consideration their other mods..if you go with a decent sz cam expect to be putting some gears out back and definantly a new stall....which either would probably be a good first mod anyways... my cam with stock gears and stall turned my truck into a turd off the line but screamed on the top in.... running 2.4 60' won't impress the ladies at the track...my cam which is a 224/220 581/581 112* doesn't wake up untill around 4000, which is fine at the track but not the best for the street...your doing the right by asking questions though.
05 RC, LME 6.0, 243 Heads, LSA Rods, 11:25 Forged Pistons, Cam Motion Custom Grind, 4:10, Eaton LSD, Narrowed Rear-end w/ Chromoly Axles, Pacesetters LT's, SLP Loudmouth II Mufflers, Volant CAI, Yank SSTB3600, Bosch 42 lbs inj's, G-Force Tune, FLT Level 4 Trany, Belltech 2/4, Times: ?
My truck has quite a bit of top end now. How do I determine where the LSA puts the opening and closing of the int./exh. valves? I want to perk up the lower end. When I launch my truck now it takes the motor a while to wind up. Once it gets up in the higher rpm range it really wakes up!