aweil

Thought you guys might be interested what I've done with my 2002 Z06, so I made a thread detailing the progress.

First, I blew up my LS6 (not on purpose).

#7 piston broke and cracked the cylinder liner into the waterjacket, this equals a trashed LS6 block, no chance for a sleeve. Water sprayed out the #7 hole while cranking so I yanked the motor and took it apart to see what the damage was.

aweil

Here's a pic of the empty engine bay....

aweil

Here are the parts I used:

LS3 block 4.070" bore, 9.236" deck height, edges chamfered and casting lines cleaned up. DOD holes are plugged. Had new cam bearings, the mains align honed, and the cylinders honed in addition to the other machine work, done by Watt.

Stock LS6 crank, polished and balanced for new rotating assembly. I did this to maintain compatibility with my Gen 3 computer and keep the 24x reluctor wheel.

Eagle 4340 h beam rods, 6.125".

Mahle 4.070" flat top powerpak setup, -4cc valve reliefs.

Stock GM .051" headgaskets

TSP LS3 CNC heads, milled .040"

LS3 intake manifold, had it ported by LG Motorsports

Comp 230/234 custom cam, should be 8.6:1 DCR at 11.5:1 SCR

I had to order wiring harnesses for MAP sensor, Cam sensor and knock sensors from Casper's electronics. I had to buy an early LS2 cam gear and bought the Edelbrock LS2 2 piece timing cover, no more yanking the steering rack for cam swaps!

aweil

Here is the engine that I bought, an L92 core from a local boneyard - I named it the barnacle:

aweil

I decided to do the engine assembly myself. I filed the rings and went with Mahle's recommendations rounded up to the next thousandth:

top ring I gapped to .019", second I gapped at .023". I'm not going to run bottle on this thing at all and want better cylinder sealing for max NA power that I can achieve out of this package. I also verified that a .015" feeler gauge fit in the gap for all of the oil rings.



The top ring was MUCH harder than the second and took probably 3x the number of turns on the ring grinder as the second. My hands hurt pretty bad by the time I was done! I assigned each ring to a cylinder and put them in bags to keep them organized so they would go where they belong when it's time to assemble the motor. You can see my ring grinder, squaring tool, file to knock the sharp edges off the rings after grinding, and various feeler gauges that I needed to verify gap.

aweil

I checked main clearances and installed the crank and torqued the main caps to verify what the machine shop said they should be.

Main bearing clearances measured between 0.00175" and 0.002".

Block with one main cap left to take off


Brushing oil passages, making sure they are nice and clean from the machine shop - they were!


Lower bearing shells installed


My old LS6 crank, rebalanced for the new rotating assembly


Assembly lube installed

aweil

I assembled the eagle rods to the Mahle pistons.

Picture showing the parts to put together. Those clips to hold the wristpin in are a bitch! I put polylube on the wristpin and wristpin bore, then some special lube for the cylinder walls, piston skirts and rings.


One piston in, I used the tapered ring compressor in the third picture to install


All done!


Bottom end


At this point I still have to torque the bolts, I have a rod bolt stretch gauge, shooting for 5-6 thousandths on the ARP rod bolts.

aweil

I installed the cam in and degreed it (yes, I know there isn't a degree wheel pointer in the picture)



Next, got the windage tray, oilpump and pickup on. Getting close!

aweil

It took probably a day to clean my oilpan, man it was dirty!

Base of the batwing oilpan:


Rest of the oilpan installed:


My SWEET 2 piece timing cover:


Looking like an engine!


All that's left at this point is to check piston to valve clearance, and drop it in!

aweil

Getting ready to get to work... got cardboard cut up for deck protection


Motor droppoed in


Heads on


Intake on. Close!

aweil

Here are preliminary dyno results, the lower curve is stock cam timing, the upper is the cam advanced 3 degrees.

mariofromnewyork

Very Nice!

Mario

C5 Pete

Nice pics!

Perhaps I missed it. What is the displacement?

ajg1915

(4.070 x 3.622) So around 380 CI

lucky131969

Good post, but I think the most important steps, and those of the most value to those considering an LS3 swap, were not documented. This would be a good opportunity for you to share all the nuances involved i.e. wiring harness/adapters, motor mounts, and problem areas, etc.

Nd4spd2

Thanks, I'm considering doing this as well. Couldn't you have installed the heads and intake on the stand before installing the engine?

aweil

The engine was 377 CID.

Walkthrough with naunces and things to consider as far as I remember:

Removing the engine was a huge pain, but not impossible. I chose to pull the motor from the top without removing the transmission or torque tube. This was a little challenging. I had to unbolt all of the bellhousing bolts, the motor mount nuts, and then prepare to drop the front crossmember. The struts were unbolted from the lower a-arms, and the upper a-arms were unbolted from the frame. I unbolted the 10mm bolt on each side which held the brake lines to the frame as well to let them drop down. At this point, remove the hood.

After that, I supported the engine from the top with a cherry picker, and the engine cradle with a floorjack. The 4 nuts which held the cradle on came off, and the cradle was lowered slowly. I let the AC compressor fall with the cradle. There is enough play in the AC lines for this to happen, but my error was not unplugging the electrical connection to the compressor... you HAVE to do this or you'll be fixing it on the car when you put the motor back in like I did.

To pull the engine out, the cradle has to fall far enough for the oilpan to clear the cradle as well as the crank pulley to clear the steering rack. You can pull the steering rack from the cradle and make some more room which would help, but it's not necessary.

After dropping the cradle, the motor must be pulled forward off of the torque tube, and it helps to have a couple friends as well as a prybar or two to do this. A jack under the torque tube to keep it level as the motor comes off will keep the torque tube from falling down and damaging your pressure plate as well. The motor will come forward enough to clear the torque tube, then up and out!

In order to get the car mobile, the cradle must be bolted back up and the front suspension put back on so the car can roll. The tunnel plate that I had was sufficient to hold the torque tube up.

The one difficult part during the motor removal was getting the power steering pump and bracket out of the way enough to move the engine forward to get it off of the torque tube.

List of items unique to LS3 install in a C5 - I will list what I used and any alternatives that I know of in paranthesis afterwards:

1. Unique lifter trays from LS3 or L92
2. Unique intake rockers, these are offset for the revised pushrod location on LS3 heads. You can reuse your exhaust rockers.
3. Unique rocker stands for the LS3 heads.
4. Different front timing cover as the cam sensor will be located here as opposed to in the back of the engine.
5. Unique LS3 valley cover. Knock sensors do NOT mount here.
6. Wiring harness from Casper electronics for knock sensors and cam sensor. This plugs into the stock plugs towards the rear of the engine and allows you to connect to the LS2/3 cam sensor (either 2x or 4x, depending on what you want to use. I don't think they're interchangeable - I will cover this in 7 and 8). Part number is 1 x Knock/Cam Harrness LS1 to LS2/LS7 (109081) = $54.95
7. LS2 or LS3 cam sensor... to my knowledge they are different depending on whether a 2x or 4x cam gear is used. Early LS2 engines used a 2x cam sensor, the same as your stock LS1/6 cam sensor. Later LS2 and LS3 engines used a 4x cam sensor and gear. If you use the 2X sensor you must use the 24x reluctor wheel on your crank, if you use the 4X sensor you must use the 58x reluctor wheel on your crank. Unfortunately, your stock Gen 3 computer is only capable of reading the 24x/2x combination. If you choose the 58x/4x (for example, if you get a crate engine with this already installed) Lingenfelter sells a conversion box to allow use of the 58x/4x combination with your gen 3 computer.
8. LS6 crank with stock 24x reluctor wheel (you can use LS2 crank, LS3 crank, whatever you want as long as the stroke is right for the rod/piston combination and you choose your cam sensor and buy a conversion box or not as needed).
9. LS3 intake manifold with LS3 injectors and fuel rail (you can use an L76 intake and other rails if you like, but you will need spacers and what not for other injectors and rails, Katech sells some of this stuff. Also, the L76 intake will be easier to use with your LS1/6 MAP sensor as it has a clip to hold it down. I had to fabricate a bracket to hold my MAP sensor down to the LS3 intake and use some silicone to seal it up). I had to modify the LS3 intake a bit on the rear to drill a hole in a plugged port in the rear to connect my vacuum line at the rear of the intake.
10. Injector harness adapters. LS3 injectors use a different connector type.. I got my adapter kit from Casper's, part number 8 x Injector Adapter EV6 to EV1 (109077) = $63.60
11. MAP sensor extension harness. Since the MAP is located in front of the engine, you will need part number 1 x LS1 MAP Extension 26" (109080) = $33.95 from Casper's electronics.
12. Throttle body adapter harness for LS2/LS3 type throttle body, I bought this a long time ago and don't know the part number but you can get it from Casper's.
13. LS7 lifters. You can reuse your stockers but the height of the LS7 lifter body is different, and you will need to measure for pushrods. In my case, I used 7.350" pushrods for a preload of .080" with LS7 lifters, block decked .006", and heads milled .040". Your results may vary.
14. I had to install my LS1/6 knock sensors on the sides of the LS3 block. To do this I had to drill and tap two holes slightly larger than they were, I want to say they were M10 x 1 but I could be wrong.
15. You will have to clearance one of your motor mounts, I want to say it's the passenger side. There is a boss on the block which interferes with the C5 motor mount. Not a big deal, take your time and trim it a bit for clearance.

lucky131969

Outstanding! I'm sure many(myself included) will appreciate you taking the time to explain the details.

aweil

The problem that I see with installing heads and intake first is that the chains which support the engine while you install it would have to go in the front and rear of the cylinder heads. I'm not sure that there is room between the head and firewall to get the bolts which would hold the chains to the head out after the motor is installed. For sure, I didn't want to find out! lol

I want to say that if you left the intake off you could fabricate a lift plate similar to this to remove the engine:

aweil

Not a problem, you were right, this thread would be MUCH more useful with more detail. I'm sure there were some subtleties that I missed. If anyone has questions, feel free to send me a PM or ask on this thread.

I have the (as far as I know) correct tables for the LS3 injectors for hptuners for the gen 3 pcm that I'll post when I get a chance, but they're on my PC laptop and I'm surfing on the mac at the time. It's not an obvious translation from one to the other but I used a 2008 C6 tune to derive the tables and driveability is pretty good so I'm pretty confident they're at least close enough to correct to work.