Does anyone know anything about 5.3's
 

I appreciate some advice before I shoot myself in the foot.

I have a 2005 Tahoe 165k with a 5.3 and I started noticing a gradual coolant loss. One google search yielded this bulletin

http://ww2.justanswer.com/uploads/Bl...t_loss_5.3.pdf

FU Castech

Figuring I would keep the truck, also figuring that the lower end is still good. I bought new heads. My question would be this. I have the stock cam out of my 2002 Z28 and I hear this cam was used in the HO version of the 327/327 and in the LQ9

http://www.crateenginedepot.com/53-L...10528C556.aspx

http://www.hotrod.com/how-to/engine/...st-comparison/

As long as I am doing heads, should I swap to the cam that I have collecting dust in my garage? Has anyone reading this done this to their truck? If so, did you have it tuned too?

Its my daily driver and I want to keep drivability, but if swapping the cam gives me a little more power I will do it. Also, if you see anything that I am missing from my parts list please let me know. Once I get this thing apart I want to get it back together, Id hate to find out I am missing something that I overlooked.


New parts I have in a pile at home include.

New style GM "706" complete heads
Felpro multi layer head gaskets
Felpro intake gaskets
Felpro head bolts
Dorman exhaust manifold bolts
GM exhaust manifold gaskets
GM waterpump & gaskets
GM thermostat
GM upper & lower hoses
GM LS7 Lifters
Delco iridum plugs
Delco plug wires
GM Timing gears & chain
GM oil pump
Timing cover gaskets & seal
GM Balancer Bolt


Used parts I have at home include:

7.400" stock pushrods out of my Camaro
Cam out of my camaro

Casting number should be on the front face of the block..... it will tell you alot.

Does that answer one questing that I asked?

:funny:
My .02 is your parts list looks good.
Stock cam 191/190 vs 2002 LS1 cam 198/208....I would spend a little more money and put a truck/torque cam in the 206/212 or 212/218 range @ 525 range.

I don't think that Z28 cam will do you much good. I put the 2002 Z06 cam in a 2004 5.3L suburban. All I can really say for the cam is the truck sounds cooler at idle. Other than that, I don't feel like I gained what I thought I would. This was my first learning experience on LS1 wizardry - Do lots of homework before doing a mod. Sucks to do them twice. Now, the Z06 cam > Z28 cam.

Can you find a couple of threads where someone says "I got 78 HP (or whatever) going to a Z06 cam"? Yes, and I can never talk people out of doing it, but rarely does someone post back how awesome of a cam it was after they do it.

Is it a good idea to swap the cam while you've got the heads off and it's easy access? Maybe / maybe not. it's certainly easier to do the valve springs while the heads are off. The actual camshaft part of the cam swap is no harder with the heads on or off. If you are not planning to upgrade the intake or exhaust, you limit your cam choices. In general, I find that a cam upgrade won't really shine until you open up the intake and exhaust and let her breathe. If your set on a cam, you'll probably want something small with a good early intake valve closing event to help build torque. think duration in the 216-222 range and intake centerline near 110.

My advice to good all around power out of a 5.3L that still drives like stock - upgrade to 243 heads, mill down to get the 706 compression, leave the rest alone. The fastest 4.8's and 5.3's from the factory came with the 243 heads. Alternately, have your replacement 706 heads worked by a good porter. Good heads always perform.

5.3 cam 191/190 .457/.466
LS1 cam 196/207 .467/.479

The LS1 cam has more duration so it will make a little more power. Lift is close enough not to matter much. How much more would just be a guess. Maybe 5-10 hp. Most of the increased duration is on the ex lobe. Is it worth pulling the front end stuff off the engine to change it? That's up to you.

I would add some new lifter trays to your pile of new parts.

If this helps on the head recommendation, I've seen enough stock 4.8's with the 243's outrun stock 5.3's with the 706's to know it isn't a fluke.

cool deal guys, thanks for the input

If you're going through all the trouble of replacing the heads, might as well port them and go with a bigger than stock camshaft.

You posted that hot rod comparison. If you notice, the 210/218 doesn't really lose much but gains a lot. The 224/230 does even better. If you pair the 224/230 with milled 5.3L heads to get compression up, most of the lower RPM torque loss goes away. Also, you could go with something on a tighter LSA like a 112 and it would bring the torque up at the expense of a little drivability.

Also, Cam Motion has Truck Cams designed to drop in and work with stock springs.

http://store.cammotion.com/53-l-325ci-101-compression-4 is a good one.

Brian Tooley also has some truck cams. The Stage III would work well. http://www.briantooleyracing.com/btr...-camshaft.html

How much does head porting cost? I see the cam is $400. Will it need a tune?

Prices vary on porting quite a bit. You will want to tune, but you might find it starts and runs on the stock tune. Just stay out of the throttle until you get dialed in so you don't detonate too much

I have a LS6 cam in my 5.7, it put down 321hp @ 5800. I want it gone.

I thought Brian Tooley had a cam change gasket kit for $49.98 that had timing cover gasket, water pump gaskets, timing cover seal and crank bolt. I cant find it on his site now but I remember seeing it.
I was wrong. $42.99 http://www.briantooleyracing.com/btr...ation-kit.html

Sounds like my camaro cam will be a lot cheaper. Thanks for all the advice. I am confidant the work i do saturday will eliminate the leak. I feel better about putting a cam in it that i know isnt scored where as the lifters make a good amount of noise when cold now. I suspect there could be bad lobe or two.