5.3 block

[Mr.Cornelius]

Hey Guys...

I have a chance to buy a 5.3 long block that comes with a Z06 cam, 799 heads and it only has 6000 miles on it...what kind of power can be expected from this setup...I have a 4.8 now will I be able to tell a differance? And is it worth $600...If I do buy it I will probley use a ls6 intake and since I have a motor in my truck now ill have the time to build it...sorry...I just dont think I can pass on this deal and wait for a 6.0...and right now im reasearching on what kind of stroke I can get out of a 5.3...what kind of power have yall got from a 5.3?

[Defunct SO]

with the LS6 cam you will notice a difference, but I would wait for the 6.0.
You can get 320 or so rwhp w/o too much of a problem, but not with the LS6 cam. As far as stroke, the stroke of the 5.3, 5.7, and 6.0 are all the same. Your 4.8 has a little smaller stroke.
Also, $600 is just an "okay" deal IMO.
Wait for a 6.0. You wont be sorry.

[GasGuzzler]

...probably use and LS6 intake...

Is a problem for me...really. Lot of fidgeting to make that work in a truck and a 5.3 is still small.....just not as small as a 4.8.

[txarkitekt]

$600 is not a bad price for a motor with only 6000 miles... You can take everything off your 4.8L and bolt it up to the 5.3L and get it running within a weekend. You can get some good power out of it, but not as much as a 6.0L, obviously. The 4.8L and 5.3L have the same bore--but the 5.3L has a longer stroke. The 5.3L and 6.0L have the same stroke, but the 6.0L has a larger bore.
If you can't wait for power--you can buy the 5.3L and run it with the Z06 cam and bolt up everything from you 4.8L and have decently more powerful motor. And then when you come across a 6.0L, you can sell the 5.3L and use that $$$ for mods on the 6.0L.

[nighthawk]

799 heads are the same as 243. that is actually a really good deal. is it aluminum block? or is it a gen IV engine?

+1 on not doing the LS6 intake, stick with the truck intake.

[nighthawk]

you could also make a 383 out of it. bore it out and get a 4.0" crank.

[txarkitekt]

799 heads are the same as 243. that is actually a really good deal. is it aluminum block? or is it a gen IV engine?

Word. That is the same thing I was thinking... The 799 heads were installed on the L33 5.3L HO motors. They were essentially the same and the 243 heads---2" intake valve/1.55" exhaust valves and all! Some say the 799 have better torque numbers than the 243s...but the 243s eventually out-flow the 799s at higher rpms... Its all in the casting of the heads. The 799 castings were more of prototype heads for the 243s. I think the only real difference is in the smoothness of the casting in the ports...
If this motor has the original heads on it, then this "5.3L longblock" this guy might be buying is the all aluminum 5.3L. He needs to go check out the casting on the block of that motor. If so, $600 is an AWESOME deal for an L33 motor!!!!!

+1 on not doing the LS6 intake, stick with the truck intake.

[nighthawk]

If this motor has the original heads on it, then this "5.3L longblock" this guy might be buying is the all aluminum 5.3L. He needs to go check out the casting on the block of that motor. If so, $600 is an AWESOME deal for an L33 motor!!!!!

yup, the only way its not a L33 is if 1. the person installed the 799 heads on a normal 5.3 block or 2. if its a early Gen 4 engine because some of them had 799 heads also.

[txarkitekt]

...
If this motor has the original heads on it...

yup, the only way its not a L33 is if 1. the person installed the 799 heads on a normal 5.3 block

EXACTLY

if its a early Gen 4 engine because some of them had 799 heads also.

An L33 is a Gen III motor. No Gen IV L33 motors were made. The LH6 is the Gen IV aluminum 5.3L motor...and the LC9 is the FF aluminum 5.3L Gen Iv motor.

But like I said--he needs to go look at the motor and check for casting numbers.

[zeake]

Not worth the effort. unless its the all aluminum motor.