Hi I am wondering what camshaft would work best with my setup? it's in a 2004 tahoe 5.3 lm7 4l60e 2500-2800 stall converter 373 gear's going to drive this on the street this is also going to be a e85 set up. The motor set up is a custom 9-10cc dome pistons 13:1, gen 4 rods, stock 706 heads Pac's 1219x springs, long tube headers, stock intake maybe ls1 trying to keep the rpms 6200 max. The camshaft's I have in mind, cam motion 222/232 595/587108, Howards 226/232 578/587 112, Howards 218/230 525/525 115, isky 218/229 575-575 108-112 custom.

 

What exactly is the point of 13:1 when you’re only looking to rev to 6,200rpm and a stall rpm of 2,600? So you want an engine that requires race gas even though it’s only gonna have the performance of maybe a stock 6.0? None of this makes sense.

 

Explain how it's not going to make more than a stock 6.0? I don't know about you but I want Torque/HP from 3,000 to 6,000 and certainly want it down low for a street driven heavy *** Tahoe. Compression is your friend and will help everywhere and he's running e85 not race gas.

 

It's a 5.3; stock heads. Small intake valve. Doesn't need a real huuuuuuuuujjjjjjje duration split like most of those. 6° ought to be plenty; maybe even more than necessary. Certainly won't need 12°. Doesn't need awholehelluvalotta duration either, being the small motor.

Smells to me something like 216°/220° on maybe a 110° - 112°LSA, "high lift". But I'm no real expert or anything, just some yutz on the Internet.

Gonna have to be E85 100% of the time.

 

And when you’re still getting smoked by stock 2v mustangs all while averaging single digit mpg, you’ll realize how stupid all of this is. But go ahead and spend more money each year on fuel costs than what a larger engine with a normal c:r would have cost.

 

That's not what I asked at all, You said it would make the same power as a stock 6.0 and you would be completely wrong, As far getting beat by a stock 2v mustang, I didn't see anything in his post where he said his goal was to race an almost 5,000lb truck against a pony car. He seems to have a plan to build an engine that will maximize torque at a lower rpm range......what would that be good for???...... I know...... A 5,000lb TRUCK!
I'm not saying you're stupid but you obviously don't know the benefits of higher compression like better fuel economy and more torque. E85 is cheaper so cost versus MPG is about the same but you get more power/torque. He's giving up a little if he chooses the ls1 intake over stock truck style but the 706 heads are a good choice even with the small valves for rpm range he's wanting to run.

 

Typical rule of thumb is each point of compression is with 3% of power. Pretty easy to do the math and see what makes more power.

 

I'd go with the 2nd cam, the Howards. I've used the 110, 112, 115 LSA versions of that cam and I really like that duration/lift range for most mild street engines.
First and last cams will close intake valve too early for that much compression.
Not that it'll cause any real issues with E85, but there will be a point where closing it earlier will reward you far super-low torque gains than you're giving up everywhere else. Diminishing returns kick in eventually.

 

Custom forged pistons then jacking up the CR to 13.1 with shitty flowing 706 heads running on pump gas?

If I'm investing in a forged bottom end.. give me reasonable compression with maybe a set of (243/799) good flowing heads...

then choose the camshaft profile.

 

They aren't shitty flowing heads for the engine size and RPM he intends to run and they actually made more power on the dyno against the supposedly better flowing stock 243 heads on a mild 5.3 and better torque down low on mild 6.0

 

706 heads are quickly proving themselves NOT to be the "throwaway" heads many once thought they were.

 

I like the 2nd or 3rd cam . Very interesting build. Those 706 heads are not going to hurt this build at all. They flow plenty on a 5.3 as others have said.

 

Interesting build. Yes compression is good from bottom to top and we wouldn't be afraid to spin it quite a bit harder. SUM-8720 218/227 112 + 2 .600/.600 is one possibility if you are wanting to maximize punch where your converter hits. We have the slightly larger SUM-8713 and SUM-8714 cams designed to work with our LS6 springs. We carry the Cam Motion, Howards and Isky Cams. If you want to see the valve event details, you can punch the numbers into our cam timing calculator. If you don't have the advance numbers, most of the cams have cam cards on our site. In addition, if you are wanting to tweak and advance or retard the cam, we've just released our new Pro LS Single Roller adjustable billet sets and even stand-alone upper gears designed to work with LS2 chains to save a bit more coin.

 

How did you come up with your compression number?

 

someone came up with it for me in it was wrong lol. It is going to take +12cc of dome in a 0.40 gasket.

 

I'd definitely run a newer style truck intake over the ls1 intake.

I had a 2000 silverado 5.3 with:
longtubes
212/218 texas speed high lift cam
late model truck intake stock heads, 92mm throttle body
electric fans
trailblazer stall
4.10 gears
engine never been out the truck, heads never been off
I pulled my 7500lb camper with this truck. it pulled it pretty well and the truck actually hauled *** for a old *** truck. I had my son drive the 2000 silverado and I drove my 2017 silverado 5.3 6 speed truck, we raced. That old *** truck walked away from the newer truck so bad it was funny. It would also outrun my 2013 v6 accord coupe which ran 13.90's. well thought out combo will go a long way.