I have a 01 5.3 silverado, runs great! Had 262,000 miles on here, never had any issue. Been in my family since 3 miles, my dad use synthetic since day 1, I have used it every 3,000 miles, and then again it never had any issues. Starts up perfect everytime.

Now I said to him I was going to do a mild cam in it, the Texas Speed Performance 224r with a 112lsa. He SaYs not only with the decreased gas millage, it'll blow up.

My other question is that I was planning on getting a set of 20s or 22s Silverado SS rims, but my brother says if I go from a 16 to a 20 or 22, I'll also loose power.

My question Is should I just cam it and do bigger tires or should I just be safe a buy a rebuild kit piece by piece till I'm ready to pull The motor out?

 

Go for it
See what happens

 

The engine will not blow up just because you change the cam in it. Assuming you do the swap correctly, you will be asking the engine to produce more power from it's elderly, diminished capacity. GM designed these engines for 250,000 and you're beyond that regardless of maintenance intervals or quality of oil.
By adding thirty degrees of camshaft duration from stock, the power band will move up the rpm scale, thus NOT ideal for a heavy truck unless you have other supporting modifications:
Stall converter and headers......plus a retune after cam swap
Lastly, the larger, heavier wheels will affect the gear ratio and act like a giant torque robber.
Again the torque converter comes into play with helping this situation.
Higher stall equals more slipping, friction causes heat, and again for the record, how many miles has that transmission been dealing with a five thousand pound vehicle ?????
The cam swap is the easy part....making it work and accomplish what you want is the difficult part.

 

I agree with the two post above. Put a "truck/torque" cam in with of course correct springs and push rods.
These LSx engines never cease to amaze me...I just tore down a 385,000 LQ4. The cam, crank, bearings, rockers, etc. could be passed off as a <100K motor.

 

Thanks guys!


I will rebuild the the valve train, maybe port my heads, get all that done, get a mild cam, a torque converter, some rims and tires, I already has 3.73 stock but with a Auburn Locker instead of factory eaton, I like that alot. The transmission was rebuilt at 256,000 cause the sun shell blew when I was on a hard pull in second, but I had the updated parts from gm put in there. Guess my main question is, am I going to prolong it's life or shorten it?

 

Rebuilding the valve train and a new oil pump would probably be a good move. It's sort of a toss up on a high mileage engine though. Have you done a compression or leak down test?

 

If you do the cam, upgrade the push rods, valve springs, rocker trunnions, new oil pump and timing gears/chain/tensioner.

 

I can't think of anything you'd be HURTING by doing a cam swap. You'll need some valve springs anyway... Let'er eat