02sierraz71_5.3

iTrader: (2)

How has tried a cam with less than a 110 LCA/ICL and less than 216 duration? Any dynos?

N4cer

iTrader: (11)

Out of curiosity, why?

02sierraz71_5.3

iTrader: (2)

cam for a 5.3 truck motor

N4cer

iTrader: (11)

LOL that's kind of important info man. Different size motors need different sized cams.

02sierraz71_5.3

iTrader: (2)

True, but motor specs were left out on purpose. Its easy enough to put a cam into perspective vs cubes. All Lsx based motors behave very similarly regardless ,they all respond to the same range of valve events.
Do you have any info regarding a cam like the one above?

N4cer

iTrader: (11)

Thought I might, but not for a 5.3L. Just general cam knowledge. Sounds like you're talking about a cam with very little mid-upper RPM HP.

02sierraz71_5.3

iTrader: (2)

Post it up, thats why I didnt mention the motor size I didnt want to run into this.

brad8266

iTrader: (23)

Well cam behavior is partly dependent on engine size so it very relevant.

67Ranger

iTrader: (16)

if you want to use it on something with electronics, it will be hard to have that much overlap. It messes with the vacuum signal, and more than likely wont idle or run well.

LSXNV

iTrader: (1)

from what i have read and learned first hand. tight lobes tend to be more for higher rpm and have less area under the curve. at the extreme side of things, a drag car with 5500 rpm stall and a 75-8000 rpm shift wont care much about the area under the curve. and thus have a tighter lobe, but someone who needs off-idle torque to pull to 5500 or 6000 will be more interested in that area. thus the wider lobe. vaccum needs, emissions, idle characteristics all givin up to the tighter lobe. you will also lose your efficiency to nitrous or tubos due to the overlap. this is coming from an old school train of thought though. i ran a 106 lsa on my 455 Pontiac, and i am going to a (wide for me) 110 to help the nitrous and give me back some vacuum (power brakes). with the 270 @ .050 dur. i will still have a lil thump to the idle.

hammertime

iTrader: (1)

I ran a comp 268H in a SBC 350 for years. All the hi-energy grinds are on 110LSA, 106ICL. That one was 218/218, .454/.454 lift. Had great torque around town and still got good mileage (15+ mpg with a freebie Q-jet). Duration, per cube, you are pretty close at 216 in 326 ci.

Oh, and I shifted it at 6000 all the time. It was done about 57-5800.

A 216/216 on 110 cam has -4 degrees overlap. A common 224/224 on 112 cam has more at 0 degrees. Which cam do you think would idle better? Heck, the 224/224 on 114 cam also has -4 degrees overlap and still passes emissions in a 5.7L.

N4cer's cam has 14 degrees of overlap (sorry to pick on you!) and I think it still daily driver material for him.

02sierraz71_5.3

iTrader: (2)

Finally someone with some input regarding the question at hand.
Thank you.

BTW: Great sig that says it all

hammertime

iTrader: (1)

Are you running headers, exhaust? I've given some throught to a truck cam for a potential tow vehicle, and I'm curious what you've arrived at so far.

02sierraz71_5.3

iTrader: (2)

I guess I should put the mods in my sig.

milled heads .05, 2" intake valve back cut ferrea 6000 series, valve job, unshrouding,stock ports, thorley headers 2.5"y pipe to 3" single, CAI, 3k stall, lpe gt2-5 cam

That setup in my 5.3 ran a 13.9 1/4 at 96mph (8.8 1/8) race weight was 5300lbs ECSB z71 she cut consistent 1.9 60's.

I recently put the stock stall back in and am swapping the cam, Ill let you know the results.
One thing I can say for certain is consideration should be given to the truck intake ahead of other aspects.

hammertime

iTrader: (1)

How did the power peak work with the GT2-5? I see its a 222/222 on 112 grind. I would imagine that cam would peak higher than your intake is designed to, so your upperend performance was probably a little choked. Seems some people have discovered the same phenomenon with LS6 and FAST intake when they are trying to spin the motor to 7000+ rpm.

I'd be curious to see how a 212/218 or 214/220 cam on 110LSA would perform.

Ragtop 99

iTrader: (7)

Interesting. I suggested a 214/220 111 to him in a different thread. XFI/Xer lobes.

02sierraz71_5.3

iTrader: (2)

Your absolutely right the truck intake cutoff at least 700rpm worth of peak power. I had the best luck shifting right before 6000 at 5950 but thats really because of the intake.
I had a buddy drop .4 in the 1/4 just from swapping to an ls6 intake, I dont care what anyone says the truck intake doesnt make anymore down low in fact its the opposite. The ls6 makes more power throughout the range especially with an aftermarket cam that doesnt shut the IV at 28(.05 stock truck cam). I think thats the key behind the truck intake design the use of a very early intake closing, if your cam is past 33 IVC look elsewhere. But thats really speculation.

I really like this lpe cam for 250 it cant be beat but itd be best with a SCR of at least 11:1

Im partial to single splits.
Ive been reading about alot of blowdown from bias hurting lowend power.
I finally decided on a 212/214 108/107 Im expecting shift points around 5600 and lots of area under the curve but we'll see. This is with a stock stall so I couldnt go crazy.

JakeFusion

iTrader: (7)

Maybe a Comp LSK 215/215 .601"/.601" 106 LSA 106 ICL.

IVC of 33.5.

Would run best with 10.2 to 10.5:1 CR (DCR of 8.5-8.75:1).