DavidGXP

iTrader: (14)

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. 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

StealthV8

iTrader: (1)

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.

06MonteSS

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...

someday

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...

StealthV8

iTrader: (1)

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

Pauls325

iTrader: (1)

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

06 SS

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).

DavidGXP

iTrader: (14)

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

Jayzvette

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!

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

98catfish

iTrader: (13)

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 *** FWD.

Doug

DavidGXP

iTrader: (14)

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 ***! 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.

4doorSS

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

Jayzvette

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.

98catfish

iTrader: (13)

I apologize I misread the post.

06MonteSS

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...

montyss07

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.

TiredGXP

iTrader: (2)

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.

Bryan921SS

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.

TiredGXP

iTrader: (2)

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

ChipC

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