iregret

iTrader: (4)

So I've been doing a lot of thinking lately. I've got a 2000 Silverado with the 5.3L. At first I was thinking about picking up another gen 3 engine and keeping it for a back up. Now I'm thinking about buying a 2007+ 4.8L. I've read that they have stronger rods and are boost friendly. (Resistant to detonation, improved intake, bigger throttle body, ls7 lifters, ls2 timing chain/oil pump, and better heads)

I've called around to my local wrecking yards and it looks like a lower mileage ly2 goes for approximately 1300.00 around here. I could shop around and probably find one in the 1000.00 range. It really depends on the mileage.

I'm wanting to do a cam swap. I've read that it's also a good idea to swap to head studs and arp rod bolts. I think I'll have to pull the engine if I change to head studs and if I change to head studs I should swap to LS9 head gaskets.

Well rather than pull my gen 3 5.3L and then spend all that money swapping head studs/gaskets, cam etc, wouldn't it be easier to do all of that to a better engine on a stand? Then I could keep my stock one as a back up.

I don't know how hard it is to swap from gen 3 to gen 4.

What do you do about the knock sensors?
What do you do about the cam/crank sensors?
Would I have to change the reluctor ring or is there an adapter or something?
What about the throttle body? I have a cable now. Would I have to switch to drive by wire?

Here are the parts I've collected and my game plan for my build.

Turbonetics ceramic ball bearing 76mm turbo, HP76mm compressor with a F1-68mm turbine and .81 A/R

KB Racing intercooler with Tial 50mm BOV

KB Racing hot parts with 3.5 inch downpipe, and JGS 40mm wastegate

2002 LS6 cam
204/218 int/exh @ 0.05" duration
0.551" / 0.547" int/exh lift
117.5 LSA

LS7 lifters

60lb injectors

Aeromotive 340

LS1 e-fans

4L80E, hd2 shift kit

Yank SC3000 stall torque converter

NP149 AWD transfercase

40K transmission cooler

Trutrac

I also have 05+ front brakes with SUV dual piston rear caliper's and hydroboost. My truck is lowered approximately 3 inches all the way around with Hellwig swaybars and Monomax shocks. I'm also running 20" Centerline Stingray III's with new Firestone tires.


Then, even after all of that, is it worth it? How far can you push a gen3 engine? The gen 3 4.8L goes for around 500.00. Maybe I should just pick one of those up?

I guess what I'm asking is this; How much power can I make with a single 76mm turbo and can a stock bottom end gen 3 LS engine take it? Can I make 700-800 horsepower at the engine?

Would it be easier to find a gen 3 4.8L and upgrade it to the newer rods?

nonnieselman

iTrader: (10)

Wow thats alot of stuff to answer..

Any 2005 newer has the LS2 rods in it.
Dont have enough time to go thru and answer all the other stuff at the moment

grey matter 04

iTrader: (9)

gen 3 vs gen4
knock sensors are on side of the block buy and extension harness..$100 or less
cam sensor is moved to front timing cover..buy extension harness
crank sensor needs a conversion box 24x vs 58x relucter wheel on crank..$200
throttlebody buy a 90mm cable throttlebody probly $400

iregret

iTrader: (4)

So it looks like I'd be in around 800.00 in adapters. How much stronger is the 07+ 4.8 verses the gen 3?

Right now they have a 4.8 out of a 2001 Silverado at my local wrecking yard with 195-200 compression for 500.00.

It seems like it would cost me over 2000.00 to swap to a gen 4.

Thanks for the help fellas.

iregret

iTrader: (4)

Are you saying that there are gen3 engines that have the stronger rods? I was under the impression that they were only in gen4. How would I tell if I were junkyard shopping?

Thank you.

Mangled03gmc

iTrader: (95)

What about a 2005-6-7 engine, it would have the same sensors as the pre 05-06's-07 classics

nonnieselman

iTrader: (10)

Its not worth it..
look at Foose,, is is putting 600+ to the wheels on a 03 4.8..
If the tune is right and run good fuel, you have a long ways to go before you hurt anything.. might bend a rod before something else gives out.

nonnieselman

iTrader: (10)

2004 was the year that they got LS2 rods, depends on when it was built.
So i said 2005 to cover that.
Get the VIN from the truck it was pulled from.
OR pull the pan and look at the rods.

iregret

iTrader: (4)

Alrighty. Hmm, well I guess I'll forget the idea of swapping to the gen 4 then. Are there different intakes or heads I should run?

This is what I think I'll do then.

Buy a gen 3 4.8L
Install ls9 head gaskets
Install arp rod bolts
Install arp head studs
Install ls7 cam
Install ls2 timing chain

Anything else? I'll search for foose's build up.

This will be my first time turboing and tuning. I'll be going very slow, but how far can I push this with my 76mm turbo?

RezinTexas

as stated, some 2004 Gen 3 motors had the Gen 4 rods. My 04 5.3 did.