How to Install an LS2 in an LS1 car

[HSV-GTS-300]

To utilise the existing LS1 harness and LS1 computer the simplest way is to convert the new block back to 2005 LS2 spec.

Step 1

Inspect your new block.

When looking towards the rear of your new engine on the passenger side at the back, behind where the starter goes is the Crankshaft Position Sensor. What colour is the actual sensor ?

Black..[you have a 24x crankshaft reluctor wheel].. go to Step 4
Grey ..[you have a 58x crankshaft reluctor wheel].. go to Step 2


Grey Crankshaft Position Sensor (CKP)
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2cranksensor.jpg

[HSV-GTS-300]

Step 2

Grey Crankshaft Position Sensor..[you have a 58x crankshaft reluctor wheel]....[you also have a 4x camshaft timing gear]..

The LS1 computer can only work with a 24x crankshaft reluctor wheel and black crank sensor.......and can only work with a 1x camshaft timing gear.

Changing the Crankshaft Reluctor Wheel

2a You need to drain the oil and remove the oilpan. You need to remove the Crankshaft from the engine. The reluctor wheel is shrunk onto the crankshaft.

Pic of 58x Crankshaft Reluctor on Crankshaft
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/58x.jpg

Pic of 24x Crankshaft Reluctor on Crankshaft
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/24x.jpg

Pics of 24x Crankshaft Reluctor Part No 12559353
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/79e4_1.jpghttp://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/7a66_1.jpg

2b Removing the 58x reluctor wheel and installing the new 24x reluctor wheel correctly is not something you want to try at home.
To install the 24x reluctor and align it correctly you need an oven and a special alignment tool.

Pic of Goodson Alignment tool in use.
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/goodsonRRJ-350.jpg

This process is best done by a professional engine builder. Even using the tool it is still possible to install the 24x reluctor upside down......and then your engine wont start.

2c Re-Install the Crankshaft with the newly installed 24x reluctor ring into your engine.

2d Change your Crankshaft Position Sensor ....remove the grey (CKP) and install a black LS1 Crankshaft Position (CKP) Sensor Part No 12560228

[HSV-GTS-300]

Step 3

....[you also have a 4x camshaft timing gear]..

The LS1 computer can only work with a 24x crankshaft reluctor wheel and black crank sensor.......and can only work with a 1x camshaft timing gear.

Pic of 4x Camshaft Timing Gear......3 bolt, 2006 style [will not work with LS1 computer]
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/camgear.jpg

Pic of 4x Camshaft Timing Gear.........1 large central bolt, 2007+ style [will not work with LS1 computer]
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/100_0770.jpg

Pic of 1x Camshaft Timing Gear.......3 bolt, 2005 LS2 style
Part No 12576407
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/camgear-1.jpg

If you decide on a double roller timing set, then you'll need the LS2 double roller version. It has the 180 degree (1x) timing lump on the cam gear. [The LS1 cam gear has no timing lump]
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/L76/SLP55003.jpg http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/L76/JP5623T.jpg



3a
You need to have a 3 bolt cam core fitted.....any LS1 style cam will do, or a stock 2005/2006 LS2 cam. The 1x Camshaft Timing Gear will only fit onto a 3 bolt cam core.

Pic of 2005 style LS2 Camshaft Timing Gear assembled.....this is the only LS1 computer compatible arrangement.
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2camgear.jpg



3b
LS2 Front timing Cover.
The LS2 front timing cover includes the Camshaft Position Sensor (CMP).

The latest LS2 front timing cover
Part No 12600325 has a grey CMP sensor....this still works with 2005 LS2 1x Camshaft Timing Gear

Older Style LS2 front timing covers (no longer available new from GM) had a black CMP sensor...they work with 2005 LS2 1x Camshaft Timing Gear also
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/timingcover.jpg
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2timingcover.jpg


So you've completed the Crankshaft Reluctor Wheel swap to 24x, the Crankshaft Position Sensor to black, and the Camshaft Timing Gear to 1x......proceed to Step 4. You have Converted to 2005 LS2 specs.

[HSV-GTS-300]

Step 4

You need to check and measure the oilpan on your new LS2 engine to ensure it fits in your car.

Alternatively clean thoroughly and then swap the following from your old LS1 engine onto the new LS2 block.

Oil pickup tube with a new O ring
Windage tray
Oil pan
Dipstick tube
Dipstick

[With some LS2 engines the dipstick tube fits into the lower section of the block....not into the side of the oilpan. If your oilpan takes the dipstick tube directly.....then you need to plug the dipstick tube hole in the lower LS2 block......a small aluminium freeze plug should do the trick]

Check/refill the LS2 with oil.

[HSV-GTS-300]

Step 5

Fitting LS1 Knock Sensors.

The LS2 knock sensors are a 2 wire type and have a small thread (M8). They are located mid block down near the pan rail. Follow this diagram to install single wire LS1 sensors Part No 12589867 on your LS2 block.

http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2Knocksensors.jpg

[HSV-GTS-300]

Step 6

Inspect the Crankshaft Harmonic Balancer and Waterpump Pulley.

Pic Corvette style Balancer and W/P Pulley
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2_sensor.jpg

Pic 2004-2006 GTO/F body style Balancer and W/P Pulley
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/L76/P1010127.jpg

The belts both run about 3/4" further away from the block with GTO and Fbody than with the Corvette Style. You may have to change the waterpump (you cant just change the pulley) and the Crankshaft Harmonic Balancer (Crank Pulley) to suit the pulley alignment of your cars current belt driven accessories.

Pic GTO/Fbody Harmonic Balancer (Crank Pulley)
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/12553118.jpg

Pic Fbody v Y body (Corvette) Harmonic Balancers
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/bothasppullies.jpg

Pic Corvette Style Water Pump
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/P1010043.jpg

Pic Fbody/GTO Style Water Pump
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/10173.jpg

Harmonic Balancer Bolt Part No 12557840

[HSV-GTS-300]

Step 7

Install Flywheel/Flexplate as per LS1.
Install Engine Mounting brackets as per LS1.

Install the LS2 engine into the car.

Connect bell housing, clutch, gearbox etc as per LS1.
Connect headers as per LS1.
Install front driven accessories as per LS1.

If you are using an LS2 intake manifold, or an [LS3/L76 (for L92 heads only)] intake manifold.....these have the MAP sensor at the front of the intake. You will need a MAP sensor extension harness. See below Pic.

You will need a Knock Sensor extension harness to reach from the valley area down to each side of the lower block where the knock sensors now are. See below Pic.

You will need a Cam Sensor extension harness to reach from the rear of the block to the LS2 front timing cover. See below Pic.


MAP, Cam Sensor, Knock Sensor extension harnesses.
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/203740-LS1toGen4K.jpg

Depending on the Manufacturer of the Cam Sensor harness extension, it may plug directly into the cam sensor or it may plug into the end of the short GM extension. Cam sensor female socket and short GM extension female sockets are slightly different.

Cam Sensor Extension Harness plugs in.....
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LS2-550.jpg

It is possible to make your own extension harnesses.....all are straight through wired, except the cam sensor extension harness.
Cam Sensor Extension Harness is a Cross-over. See Pic below.
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/Cam-Wires.jpg

If you are using LS2 fuel injectors you will need EV6 to EV1 injector harness adapters. See Pic Below.
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/P1010184.jpg

Connect all electrical harnesses and the appropriate extensions in the same areas as you would with an LS1.

[HSV-GTS-300]

Step 8

Throttle Body.

If you are using the LS2 90mm intake manifold or LS3/L76 (in conjunction with L92 heads only) 90mm intake manifold then you probably received an Electronic 90mm Throttle Body.
90mm ETB pic
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/0405htp_ls2_14_z.jpg

There is currently no simple or cheap way to convert these ETB's into cable drive to suit older cars.
For cars already fitted with a Fly By Wire foot pedal and originally fitted with a smaller LS1 ETB there are adapter wiring harnesses available to suit the newer 90mm ETB's.

For older cars without Fly By Wire, the answer is to fit a 4 bolt 90mm cable type Throttle Body. You will also need to buy a new cable bracket to fit the 90mm intake manifold......except the Holley 90mm does come with the necessary bracket.
Pic of 90mm Cable TB
http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/HOLLEY90mmTHROTTLEBODY.jpg


Another option you have if your LS2 is fitted with cathedral port heads is to re-use your old intake manifold/injector/throttle body combination off your LS1.
This would save having to buy a 90mm cable throttle body, MAP extension harness and fuel injector harness adapters.
The LS6 intake, FAST 78mm and FAST 90mm all perform as well or better than the LS2 90mm intake manifold.
[Stock LS2 heads , casting number 243 are cathedral type.]

[jmd]

Great info mate. :2thumbs:

[HSV-GTS-300]

Here's a neat kit if you're starting with an unfinished Gen4 block.

http://i2.photobucket.com/albums/y20/PerthPurplePenguin/car%20parts/LSCK24X-flat-small.jpg

SDPC has put together a complete kit of components that are required when you upgrade from a GEN3 (LS1 / LS6) engine to the newer GEN4 design. (Wet sump only)

The kit includes:

Gen4 front cover kit with sensor
Gen4 valley cover kit
Gen4 lifter guides w/bolts
Gen4 timing chain dampner
Billet single roller timing set (specify 24x or 58x application)

http://sdparts.com/details/scoggin-dickey-parts-center/sdls2ck-1

[4mulaJoe]

Awesome info man! Thanks for taking the time to put this together.

Do you think it makes sense to order that SDPC kit if you want to use an aftermarket double roller? I also wasn't sure if it came with the seals and gaskets needed for the front cover.

An additional note, for an ls6 car you will need some spare 3/8" hose to re-route your pcv.

[HSV-GTS-300]

Go here and download the 2011 GMPP catalog
http://www.ls2.com/forums/showthread.php?t=850131

Get part numbers to make up a kit without the timing chain
Google part numbers to get prices etc

Front timing cover comes with Cam sensor, bolts, crank seal, cover gasket.

http://sdparts.com/details/gm-factory-replacement-parts/x12600325

[4mulaJoe]

Thanks.

[lsp]

Step 8

Throttle Body.

There is currently no simple or cheap way to convert these ETB's into cable drive to suit older cars.

Anyone figured out how to do this yet?

[flameout]

I have a 06 LS 2 from a Escalade , I see no cam sensor or any wiring on the front cover, is it possible it is located on the back of the block? Thanks

[HSV-GTS-300]

I have a 06 LS 2 from a Escalade , I see no cam sensor or any wiring on the front cover, is it possible it is located on the back of the block? Thanks

No. Stock Gen4's have no timing reluctors on the rear of their camshafts. Cam timing all comes off the front cam gear, bolted to the front of the cam, underneath the front timing cover.

If it's an LS2 then the front cover will look like either of the 2 pics at the end of Post#3 of this thread.
(It's possible that whoever removed the engine has smashed the original Gen4(LS2/3) front cover and replaced it with a Gen3 (LS1) cover they had laying around.