I am currently rebuilding my 2007 chevy silverado 5.3l and was wondering what yall think of running a. 585 cam with 283/286 duration? I'm also porting the heads to stage 2 and am curious to know about how much hp will I gain. Thnx

 

What cam ? Duration numbers off..... ? ?

 

Trick flow hydraulic roller. Numbers are right!

 

Is the casting number on your head 243 or 799 ?

It's a lot of good porters out there..... AI, Chris Frank, Brian Tooley, Tony Mamo, Greg Good and etc.....

All have they own say so about what cam be done and how much power can be gained.

 

Im not for sure what the casting number is. How much hp do you think I'll gain?

 

30 rwhp is a good rule of thumb.... Some have gained more horsepower depending on how effective their CNC program goes.

 

Duration @ ?. I can only assume those #'s are not @ .050

 

That's what I was asking.....

 

Those have to be .006 numbers. With that lift, I'm guessing a moderate ramp rate - maybe 227/233 at 050"? Also, what lobe separation angle and intake centerline? With the right valve events, that could be a great cam. With the wrong events, could be rough. Also will depend on headers. Stock manifolds and a cam with a lot of overlap don't tend to work well together

Stage numbers are relative. Alot depends on the casting. 706's I wouldn't get my hopes up. 799's or 243's will perform quite well.

 

228/230 on 112lsa at .050 lift

I would go with less duration for a 5.3l in a truck

 

Is that to big of a cam?

 

Yes it is! 220 duration max is what I recommend in a truck.

 

Y do you think that? Will it run good? Will it give me problems you think?

 

That's a pretty dull, blanket statement, not knowing what he's doing with the truck and/or other mods.

You need to be more specific about your goals and what other mods you have done, or plan to do. It probably won't cause you any issues either way, but if all you plan on doing is this cam and a couple bolt ons with the stock 5.3, you'll want a cam that's more focused on low/mid range power (i.e.- smaller)

 

The other things that are getting modded is the heads, btm end, cam and a tune. I've never really heard of ppl running that big of cam on a 5.3l chevy silverado and that's y I was asking. There usually 220,224 etc! My goals are to be a daily driver but I want the truck to run and sound good as hell. Im wanting to get around 500hp eventually but will probably have to upgrade some more to do so.

 

What do you mean by bottom end? If all you want is 500hp, you don't need to touch a damn thing in the bottom end. But you won't come anywhere close to that power with a H/C/I 5.3

 

Ok thats the advertised intake and exhaust durations. It's 228/230!!!

 

I'm go say with that cam you'll be around 450 horse at the crank. Car craft did a cam comparison on a 5.3...... A 224 cam in a 5.3 will net you roughly 440 horse at the crank.
They installed 3 different cams from crane..... A 200, 210, and the 224. The cam that really woke the 5.3 up on both torque and horsepower was the 210/218 on a 116 LSA.

 

Displacement affects where a cam will make power. A 5.3l will need to rev higher than say a 5.7l with the exact same cam and have lowend torque negatively impacted more.

With the larger displacement range the LS variants offer and the odd fact 5.7l was most common in 3500lbs cars and 5.3L most common in trucks that can easily top over 5000lbs. there are a LOT of cams out there too big for a truck with a 5.3l.

 

RIght or wrong, I tend to look mainly at the intake valve close (IVC) event for estimating "torquiness". Secondly, I'll look at the Exhaust valve open (EVO) event. Can't guess a number off a dyno, but can guess if torque will go up or down. When you have longer durations, it's harder to get the IVC event early in the compression stroke, which means you sacrifice compression, or get alot of overlap, or both. It is also hard to get the EVO later in the power stroke. Notice alot of big cam cars on here also run 11.5:1 compression? That's because they have learned how to compensate for the later IVC. Higher compressions also allow you to open the exhaust valve earlier without bleeding off as much force on the piston.

When it comes to low end torque, cranking compression is your friend. So, if you overcam a 5.3L, you end up losing that low end torque that helps get the truck moving, so you perform worse AND get worse fuel economy to boot.

How do I know? I made the mistake of putting a Z06 cam in a 5.3L suburban. Sounds cool at idle, but unless I rev the motor to 4500, it doesn't help the truck run any better. And that is a smallish cam, but the LSA is wide, so the valve events suck. If I could do it over again, I'd do something like 218 / 226 on a 110 LSA with no advance. You'd have 2 degrees of overlap, so you'll get that cool idle, still be streetable, loads of cranking compression, and a late EVO to get as much from the fuel explosion as you can