LS4 Performance - How about a Z06 5.3?

I found a LS4 engine with 30,000 miles on E bay that I'm thinking about buying. I just don't want to pay for the shipping. I was thinking about putting in a Z06 cam, lifters, valley tray, comp cams push rods, 130lb springs with Harland Sharp 1.7 rockers, and a Z06 intake. I will have the stock exhaust manifolds ported and possibly extrude honed and coated buy a local shop. I should be able to do all of this for 2,500. I just need to figure out a way to pull my engine.:confused: I think I can do this from the top with out having to drop the cradle. The trans will also get some 3.69 gears while every things apart. If I do get this engine, then I wouldn't install it initial next spring, and if I don't get it, then I may use my engine but I like the idea of having a spare.
I figure 370hp/350tq

I think all the rear wheel drive 5.3L's are a little longer and wont fit in a fwd. I dunno for sure but its what i have been told.

correct... the truck/rwd 5.3 LS4's are different blocks/parts - they are longer, and won't fit in our FWD vehicles.

but if you ARE talking about a fwd 5.3 from another fwd car like ours, I don't think the cam nor the z06 intake would fit anyway...

if its an LS4, then its the fwd version... i think the Z06 cam would move the power band up too high for that small of an engine... the old school 211/218 cam would make a good choice i believe...

i think someone has already done a stock Z06 cam swap into our engines, just don't wanna search now

yeah our engine is an inch shorter and everything is run off one belt and our flywheel is not the normal one but if it says ls4 thenyou are probably good

LS6 cam (if you are talking about the 2001-ish years) is pretty dang close to the LS2 cam that has been put in. I forget the exact gains, but it was more like 335/335 (flywheel).

LS6 cam (if you are talking about the 2001-ish years) is pretty dang close to the LS2 cam that has been put in. I forget the exact gains, but it was more like 335/335 (flywheel).

But with a Z06 intake, roller rockers, and ported manifolds the gains would be even more.

5.7 Z06=71.05 hp per liter and with the same parts on a 5.3 should equal 376.5 hp but at a higher rpm

correct... the truck/rwd 5.3 LS4's are different blocks/parts - they are longer, and won't fit in our FWD vehicles.

but if you ARE talking about a fwd 5.3 from another fwd car like ours, I don't think the cam nor the z06 intake would fit anyway...

block/parts are the same length. only the front drive accessories are shorter. Thats why the 243 casting head is from the z06 5.7 liter motor. If the block were shorter they would not fit!:chug:

The only concern with running the Z06 top end would be disabling the dOd and clearance with the stock hood:chug:

block/parts are the same length. only the front drive accessories are shorter. Thats why the 243 casting head is from the z06 5.7 liter motor. If the block were shorter they would not fit!:chug:

The only concern with running the Z06 top end would be disabling the dOd and clearance with the stock hood:chug:

Maybe I'm blind but where did the op say anything about heads? Also hes talking about a LS4 which is a FWD and his car is FWD. He doesn't want to put a 5.7 in his car he was asking about a Z06 CAM in a LS4.

Op good luck it sounds like it will be a fun ride when your done. Then throw a 125 shot into the mix and you'll have a bad ass FWD.

Doug

block/parts are the same length. only the front drive accessories are shorter. Thats why the 243 casting head is from the z06 5.7 liter motor. If the block were shorter they would not fit!:chug:

The only concern with running the Z06 top end would be disabling the dOd and clearance with the stock hood:chug:

This is why I would use the Z06 lifters and valley cover. Other mods would be required but shouldn't be to hard. I would need to make a TB adapter, reposition the oil sender, use some LS1 injectors and fuel rails with pig tail adapters, and move a few vacuum hoses but all in all without DOD and with some 3.69's this thing would be hauling some serious ass! I am in the process of selling my 455 Cutlass to allow some room, and some more funding for this project. I'll see what happens. It may take awhile but somethings going to happen.

all that sounds good i was thinking about doin LS6 cam and intake manifold maybe even the throttle body i dont know yet im trying to find the best combo that wont cause problems with the DOD

Maybe I'm blind but where did the op say anything about heads? Also hes talking about a LS4 which is a FWD and his car is FWD. He doesn't want to put a 5.7 in his car he was asking about a Z06 CAM in a LS4.

Op good luck it sounds like it will be a fun ride when your done. Then throw a 125 shot into the mix and you'll have a bad ass FWD.

Doug

He didn't say anything about heads. 06montess claims the block is shorter in the LS4 which it is not. That's why I made the comment about the heads. If the block were in fact shorter the Zo6 heads would not fit.

I apologize I misread the post.

aaah, gotcha...

I thought I had seen/read somewhere that they WERE shorter, that they were different from the ones in the trucks...

sorry, my bad...

This engine is adapted for transverse front-wheel drive applications. In order to fit into the smaller engine compartments designed for V-6s, the LS4 engine block had to be shortened by one inch.

This engine is adapted for transverse front-wheel drive applications. In order to fit into the smaller engine compartments designed for V-6s, the LS4 engine block had to be shortened by one inch.

Time to read the stickies again.;)

No, the block was not shortened by an inch.

The crankshaft was shortened by an inch - partly at the snout since there is a single belt drive, and partly on the flange where the flexplate mounts. Other than that the block retains the same bore and main bearing spacing as the LS1/6 blocks.

The LS4 has a more compact accessory drive and waterpump system than the LS1/6, which is what accounts for the overall decrease in engine length.

I thought that GM took the LS1 and shortened it 13mm overall.

10mm at the accessory drive = 0.393939 in

3mm at the crank = 0.1182 in

Also 1 inch is 2.54cm, so really they only shortened the entire engine by 0.5122 inches overall.

I thought that GM took the LS1 and shortened it 13mm overall.

10mm at the accessory drive = 0.393939 in

3mm at the crank = 0.1182 in

Also 1 inch is 2.54cm, so really they only shortened the entire engine by 0.5122 inches overall.

Apparently I need to read the stickies again too. 13mm it is, just 1/2 inch on the crank.

I thought that GM took the LS1...

I would also point out that the LS4 is a GenIV block so it actually has more in common with the LS2. I understand the concept you were conveying, just wanted to make sure others that are confused understand the architecture of the block.

Chip

Well, I don't think I'd use the Z06 cam after all since as far as I know it's a manual trans cam. It would work, but a custom non DOD cam would be better.

Well, I don't think I'd use the Z06 cam after all since as far as I know it's a manual trans cam. It would work, but a custom non DOD cam would be better.

When I was looking at cams, I figured this one from crane would do the job nicely: http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=1449571&lvl=2&prt=5

Nice operating range, 210/218 duration with .531 lift. reasonable idle and a recommended operating range from 1000-6000 rpm. Probably not too different from a Z06 cam. The lift is compatible still with the dod lifters, just not a dod profile.

:cheers:

What makes the dod profile different?

Doesnt it not fully open the dod cylinders' ports?

Could you use different length pushrods on those cylinders instead?

What makes the dod profile different?

Doesnt it not fully open the dod cylinders' ports?

Could you use different length pushrods on those cylinders instead?

The DOD lobes have slightly more lift. This is said to compensate for a little lost motion in the DOD lifters so that all cylinders make the same power.

On a different note, someone in the G8 part of the forum is supposedly running a test DOD cam from Comp Cams. If this makes production, it would also fit the LS4. Might make a good cam for us.

Chip

The only thing I've come across so far is that there is more lift on the lobes for the cylinders that deactivate. Something about needing to take up more "lash" in the DOD lifters.

I haven't seen any data on the valve opening or valve closing timing on any of the LS4's cam lobes, so I don't know if there is any duration/timing differences.

If anyone's pulling a cam out, it would be nice if you could slap on a degree wheel and dial indicator on and measure the opening and closing times (@0.050) on a dod and non-dod cylinder before yanking the stock cam. I don't think I'll be able to stick a degree wheel on with the engine in the car when it's time to do the rockers.

:cheers: