I used to post on here a lot before moving on to other platforms. So it has been a while. I still use this site as a basis of technical reference when I can validate the data, so I'd like to give something back. Last year, I embarked on an LS3 swap in my 2003 Corvette Z06. That car has been my race car since 2009...not a lot of people have had their C5 race cars as long as I have. When looking around for technical information, there are LOTS of bits and pieces to what it takes to make the swap successful by an amateur. The professionals know it like the back of their hand, but for someone that knows how to turn a wrench but it isn't my day job, I had lots of questions that took a lot of searching. Hopefully this tutorial help someone else in the future. This started as a swap last summer and turned into a 7 month rebuild of a LOT of the car. After 16 years as a racecar, a lot of the car was showing age or it was a "might-as-well".

Before I go any further, I need to thank a few people for their assistance along the way: David Farmer, Louis Gigliotti and his team, Corey Brown, Matt Peterson, Mark Nunnally, Kirk Lawrence, Jason Rooks, Ben Grambeau, Cassidy Nolen, Andy Stevens, and all of my fellow C5 Mafia racers. I had a couple of snafus along the way and they really helped me.

I'll start with a random list of notes/reminders/parts-to-order that I kept along the way:

2003 Corvette Z06
GM Crate LS3 “CT-525” Long Block

TO-DO – random notes
- Send spare power steering rack and pump for rebuilt (TurnOne)
- Take (4) coilovers to RE Suspension for rebuild
- Swap ATI Dampener to LS3
- Buy LS6 starter
- Buy friction plates for clutch; rebuild while apart
- 7.25” QuarterMaster Optimum-V triple disc
- Buy throwout bearing and TriLite release rebuild kit – “165” TriLite
- Swap LS6 batwing oil pan and windage tray to LS3
- Swap LS6 oil pickup to LS3
- Order new flywheel (current one cracked)
- Buy and install oil pan baffle doors
- Buy LS6 water pump and gaskets
- Buy LS3 valve cover oil fill and cap
- Two tab valve cover oil filler next; not one tab
- Buy black RTV
- Buy APR crank bolt
- Move LS6 oil pressure sender to LS3
- Buy LS6 pilot bearing (x2 from screwup)
- Buy CAM sensor adaptor/extension harness
- Check for MAP extension harness
- Buy Lingenfelter MAP extension harness
- Buy LS3 MAP sensor
- 1 BAR unit if naturally aspirated
- Buy Lingenfelter 58x-to-24x Trigger Conversion Module
- Clearance passenger side engine mount
- Buy new thermostat and LS3 housing
- Check for LS3 to LS6 injector adapters
- Order new LS3 fuel injector connects with pigtails
- Buy LS3 intake – found new intake Facebook Marketplace
- Buy LS3 fuel injectors; Got a set of lightly used LS3 injectors from a buddy; Had them cleaned and flowed for $30 each
- Buy LS2 Silver Blade throttle body – Louis Gigliotti had a unit
- Buy LS2 throttle body to C5 wiring adapter
- Swap LS6 dipstick tube to LS3
- Buy spark plug wires
- Buy front tie rod boots
- Buy square exhaust hanger bushings
- Buy tail pipe exhaust flange gaskets
- Buy new oil temp sensor connector (mine was damaged)
- Buy new K&N panel air filter for stock air intake
- Buy new K&N air bridge and cone filter
- Buy GM IAT sensor
- Buy grommets
- Get tuned by PCM
Note:
- Use LS6 coil packs
- LS6 CAM sensor located under back of intake
- LS6 MAP sensor located back of intake
- LS3 CAM and MAP sensors on front of engine

 

REMOVAL/DISCONNECT

August 2, 2024

• Disconnect battery
• Drain oil, coolant, power steering, differential, transmission
• Remove exhaust from headers to tailpipes
• Remove tunnel plate
• Remove front and rear sway bars
• Remove radiator, alternator, and power steering pump
• In retrospect, the power steering pump can stay
• Remove coil packs
• Disconnect steering shaft

August 3, 2024

• Disconnect engine oil cooler hoses
• Disconnect starter, (2) engine grounds, and (2) O2 sensors
• Disconnect transmission sensors
• Disconnect rear cradle driver side ground
• Disconnect oil level sensor
• Disconnect transmission cooler hoses
• Disconnect front and rear ABS sensors

August 10, 2024

• Build drivetrain cradles
• Front cradle: 20”x22” – two 4x4s on top of two 4x4s
• Rear cradle: 16”x20” – two 4x4s on top of two 4x4s
• TT cradle: random 2x4 pieces to saddle the TT
• All cradles on castors

August 17, 2024

• Disconnect bottom of each coilover
• Disconnect brake line holder bracket in each wheel well
• Disconnect top of each a-arm (leave attached but loose)
• Disconnect front brake cooling hoses
• Disconnect shift boot and ****
• Remove front cradle ballast

August 18, 2024

• Disconnect ground on driver side block rear
• Disconnect ground on frame rail under master cylinder
• Disconnect front and rear master cylinder brake lines at ABS module
• Place rubber hose caps on ends of tubing
• Place strip of Gorilla tape across open holes in ABS module
• Remove upper intake
• Disconnect fuel line at rails
• Place rubber hose cap on end
• Disconnect clutch hydraulic line
• Place rubber hose cap on end
• Disconnect electrical harness at battery
• Drop drivetrain onto drivetrain cradles
• Remove (4) nuts in each front and rear cradle (8 total)
• Ratchet strap front and rear cradles to wooden cradles
• Disconnect rear brake lines along tunnel
• Disconnect top of A-arms
• Raise body off drivetrain
• Watch rear brake lines in the tunnel
• Strap TT cradle to TT
• Push entire assembly outside and power wash with a pressure washer

September 1, 2024

• Remove rear brake lines from ABS module to rear diff
• Place rubber hose caps on tubing
• Place strip of Gorilla tape across open holes in ABS module
• Remove front ABS harness from TT (do not reinstall)
• Note for me only; I rewired the front wheel speed sensors with shorter harnesses from the ABS module to each wheel
• Disconnect oil cooler standoff
• Disconnect TT from bellhousing
• Separate TT from engine
• Remove bellhousing
• Remove engine mount bolts
• Remove LS6 from front cradle

September 2, 2024

• Put LS6 on engine stand
• Remove clutch
• Remove flywheel - damaged
• Remove batwing oil pan
• Remove oil pickup
• Full of metal and rubber debris – valve seals
• This was source of smoking and oil consumption

September 7, 2024

• Clean batwing oil pan and two halves
• Oil pan gaskets looked good – both
• Remove oil pickup o-ring
• Remove ATI dampener; cleaned bolt
• Remove water pump, cleaned bolts
• Built wooden cradle for LS6 block
• Move LS6 from engine stand to cradle (for sale)
• Put LS3 on engine stand

 

INSTALL/CONNECT

September 21, 2024

• Remove LS3 oil pan
• Remove LS3 oil pickup and blue o-ring
• Remove LS3 windage tray
• Install LS6 windage tray – 18ftlbs
• Install LS6 oil pickup – 106inlbs
• RTU all four corners and install LS6 upper oil pan gasket
• Install upper LS6 oil pan – 18ftlbs and 106inlbs (2)
• Install lower LS6 oil pan lower bat wing
• Install Improved Racing Baffles
• Trim LS6 lower batwing oil pan gasket
• Install LS6 lower bat wing – 106inlbs
• Remove LS3 crank pulley
• Drill and pin crank with 3/16” pin (blue Loctite)

September 22, 2024

• Install ATI damper
• Install OEM bolt to snug up damper – 240ftlbs
• Remove OEM bolt
• Install ARP Crank bolt (27mm 12pt socket) – 235ftlbs
• Install LS6 water pump and gaskets – 11ftlbs and 22ftlbs
• Grind passenger side block boss and passenger motor mount to clearance LS3 using C5 motor mounts
• Install LS3 into front cradle – 37ftlbs
• Install front LS6 steam crossover tubes onto LS3
• Install LS6 pilot bearing

September 23, 2024

• Install new QM flexplate and QuarterMaster button flywheel with ARP bolts (with QM clutch housing bolts installed)
• 15ftlbs, 37ftlbs, 74ftlbs with dab of blue Loctite
• ARP says 85ftlbs with blue Loctite and lube
• Install new QM friction plates and floater discs – 20ftlbs
• Install bellhousing – 37ftlbs
• Chased holes with tap and chased bolts with die

October 24, 2024

• Remove throwout bearing (165) and TriLite release bearing adapter plate from TT
• Remove TriLite release bearing from adapter plate
• Remove o-rings from TriLite release bearing
• Install new o-rings in TriLite release bearing
• Install TriLite release bearing on adapter plate – small dab blue Loctite
• Install Trilite release bearing and adapter plate on TT
• Install new throwout bearing (165)
• Check clutch clearance
• Measure clutch fingers to bellhousing face
• 2-27/32” or 2.84375” – measured in (4) locations
• Measure bearing face to torque tube face
• 2-11/16” or 2.6875” – measured in (4) locations
• Clutch side 2.84375” minus bearing side 2.6875” equals 0.15625” clearance
• >0.100 is good – as friction plates wear, the clearance will decrease

October 25, 2024
The project went to $h!t on this day!!!!!

• Attempted to connect TT-Rear-Cradle-Assy to Bellhousing-Front-Cradle-Engine-Assy
• TT shaft did not want to line up perfectly with clutch and pilot bearing
• Got it close, then used long bolts to pull the TT up to the bellhousing
• During final torque, stripped (2) bolt holes in bellhousing (there have been two LS6s , two Transmissions, and two Diffs -- so the drivetrain has been apart a lot)
• Pulled assembly back apart and installed helicoils
• Got it close, then used long bolts to pull the TT up to the bellhousing
• During final torque, stripped several bolt holes and new helicoils in bellhousing
• Pulled assembly back apart - ordered locking steel M14x1.5-M10x1.5 inserts
• Found damaged pilot bearing – ordered another LS6 pilot bearing
• Removed power steering rack and found front tie rod boots damaged
• Installed new rebuilt Turn One power steering rack
• Ordered new front tie rod boots
• Remove power steering pump from front assembly bracket
• Install new rebuilt Turn One power steering pump in front assembly bracket

 

November 9-10, 2024

• Remove QuarterMaster clutch assembly
• Remove damaged LS6 pilot bearing
• Install new LS6 pilot bearing
• Install clutch assembly (friction plates and floater discs) – 20ftlbs
• Used QuarterMaster steel alignment tool during install and torque sequence
  • This was the issue before, I used a generic plastic alignment tool and I did not keep the friction plates in perfect alignment. The plastic alignment tool would still go into the pilot bearing with some effort, but it was not perfectly aligned.
• Bellhousing to TT bolt holes
• Installed (2) 14mmx1.5-10mmx1.5 steel locking inserts
• Installed (2) 12mmx1.5-10mmx1.5 helicoils
• Install new front tie rod boots
• Install front tie rod ends on steering rack
• Insulate tie rod ends and ball joints
• Install bellhousing to engine block – 37ftlbs
• Connect TT to bellhousing – 37ftlbs
• Remove LS3 knock sensors from block (not using knock sensors in tune)
• Connect oil cooler stand-off and new gasket
• Install bellhousing plastic/rubber cover plates – both sides
• Install new LS6 starter
• Install Katech tensioner from LS6 block
• Install LS6 headers
• Install LS6 oil dipstick
• Install rear brake lines from ABS module to rear diff

November 17, 2024

• Install (4) coilovers, top connection only
  • Rebuild by RE Suspension
• Repair both front inner fenders with fiberglass work to cover tire rub holes
• Install power steering pump on block
• Install power steering reservoir on block
  • ***Need to connect bottom pump hose later***
• Clean bottom of car, front to rear (oil, grease, grime)
• Lower body onto drivetrain
• Watch for hard brake lines in tunnel
• Watch for shifter assembly in tunnel
• Bolt front and rear cradles (8 nuts) – gutentight
• Bolt top (4) a-arms to body – gutentight
• Bolt (4) bottom coilovers to lower a-arms – gutentight
• ***Check and route rear brake lines in tunnel and rear cradle***

November 23, 2024

• Route rear hard brake lines
  • Fasten in tunnel and over differential
  • Fasten in left and right rear wheelwells
• Route front hard brake lines
  • Fasten in left and right front wheelwells
• Route and connect rear wheelspeed sensors
• Route and connect rear brake light harness in right rear wheelwell
• Connect all transmission wiring and secure
• Connect driver side ground on frame in left rear wheelwell
• Route, connect, and secure transmission cooler hoses
• Install passenger rear wheelwell inner fender
  • Small sub-section used to protect the trans cooler pump
• Connect lower power steering pump hose
• Connect clutch hydraulic line
• Route reservoir line and bleeder lines
• Connect steering shaft
• Route, connect, and secure front ABS electrical wires
• Connect front brake cooling hoses
• ***Swapped in LS6 crankshaft position sensor at lower rear passenger side of block
  • (Stupid mistake, forgot what I was doing – LS3 needs LS3 crank position sensor)
  • Pull passenger header and starter
  • Install starter and passenger header
• Install passenger side block ground
• Connect starter electrical
• Connect torque tube wire loom
• Connects to connectors in battery tray area
• Connect crank position sensor connector
• Connect low oil sensor connector

November 26, 2024
***Installed the wrong crankshaft position sensor the previous weekend

• LS3 needs LS3 CPS – NOT LS6 CPS – stupid mistake
  • Pull passenger header and starter
  • Disconnect and remove LS6 crank position sensor; disconnected low oil sensor
  • Install LS3 crank sensor
• Connect Lingenfelter Conversion Box Crank In to LS3 crank sensor and Crank Out to C5 harness
• Connect low oil sensor
• Wrap wires in heat shield
• Install starter and passenger header
• Install passenger and driver O2 sensors (new)
• Heat shield O2 wires and connect
• Ziptie O2 connectors and wiring away from headers
• Remove LS3 cam sensor extension that came on LS3 crate motor
• Connect Lingenfelter Conversion Box Cam In to LS3 cam sensor and Cam Out to C5 harness

 

December 7, 2024

• Remove LS3 oil pressure sender from top rear of block
• Install LS6 oil pressure sender in top of rear of block
• Convert fuel injector connectors to LS3
• One by one, remove LS6 fuel injector connectors and solder in new LS3 fuel injector pigtails – proper soldering and heat shrink
• Rewrap and secure wire looms and harnesses

December 13-14, 2024

• Soldered in new oil temp sensor connector and wiring
• Mine was burned and brittle from 15yrs of racing
• Installed heat shield on the wiring harness and covered the connector
• Connect oil temp sensor in oil cooler standoff adapter
• Connect/re-connect driver O2 sensor
• Connect driver side block ground – braided ground wire
• Connect driver side frame rail – under master cylinder – braided ground wire
• Connect rear driver head ground
• Clean LS3 intake
• Blow out intake and fuel rails with compressed air
• Remove upper intake cover
• Install ultrasonically cleaned/flowed LS3 injectors
• Move air lines from LS6 intake to LS3 intake
• Move brake booster vacuum line from LS6 intake to LS3 intake
• Install LS3 intake on engine
• Torque intake bolts to 49in lbs and then 79in lbs
• Abandon HVAC vacuum line on rear of intake – no AC in the racecare
• Ensure rear vacuum port is intact or capped
• Abandon knock sensor connector
• Will not run them on the racecar
• Connect fuel injector connectors
• Install coil pack rails
• Connect coil pack connectors
• Install alternator and connect wiring
• Connect fuel line on rail
• Connect air line to intake

December 20, 2024

• Install new Schrader valve and cap in fuel rail (rail did not have one)
• Install LS3 MAP sensor
• Extended Lingenfelter LS3 MAP to C5 Harness adapter
• Proper soldering and heat shrink – line for line
• Connect LS3 MAP sensor
• Install LS2 Silver Blade throttle body
• Connect LS2 throttle body with LS2-to-C5-TPS-and-TB harness adapter
• Install serpentine belt and torque Katech manual tensioner to 25lbs and 40lbs
• Install DeWitts radiator
• Connect oil cooler lines
• Install air intake bridge
• Connect MAF
• Connect fan
• Connect battery
• Fill transmission, engine oil (Driven BR30 break-in oil), coolant (distilled water), power steering (Maxima), and brake fluids
• Uploaded LS3 C5 tune – copied from another LS3 C5 swapped car
• ***Tried to crank the motor and it will not run
  • Turns, builds oil pressure
  • Coughs and sputters; will run roughly for 5 seconds when it will run

December 28, 2024

• Install 2 tab oil filler neck and cap
• Troubleshoot MAP sensor
  • MAP appears dead on HP Tuner logs
  • LS6 and LS3 MAP sensor ohm differences
  • Lingenfelter MAP conversion harness ohms straight wire to wire
  • Trigger voltage dos not work with xxx257 PN LS3 sensor
  • Slaved in LS6 MAP sensor and loaded in original LS6 tune
    • Engine cranks and runs
• Ran to 100*F coolant temp and shut it off
  • Will run with foot on pedal, open TB about 15%
  • LS6 all-out tune with MAF enabled and LS3 injector fuel flow
• SOLVED ISSUE
  • First LS3 MAP I bought and installed was a 3 BAR MAP. LS1/6 is a 1 BAR. Bought and LS3 1 BAR MAP then found Lingenfelter LS1/6-LS3 MAP Harness Adapter was straight wired. Sense is the middle pin in the C5 harness but needs to be 3rd pin at LS3 MAP
  • Troubleshoot MAP sensor issue
    • C5 MAP connector
      • Gray – 5v reference (outside pin)
      • Light Green – Trigger Signal (middle pin)
      • Orange/Black – Ground (outside pin)
    • Lingenfelter Adapter Harness
      • Black – 5V reference (outside pin) -- C5 side C
      • Red – Trigger Signal (middle pin) – C5 side A
      • Green – Ground (outside pin) – C5 side B
    • LS6 MAP PN 16212460
      • 5V on signal wire and changes with vacuum
    • LS3 MAP GM PN 55567257
      • Ohms different than LS6 MAP
      • FIGURED OUT that this is a 3 BAR MAP, for forced induction to measure pressure above atmospheric pressure. I need a 1 BAR MAP to measure up to atmospheric pressure and below (vacuum)
    • LS3 MAP GM 55573248
      • Bought Advance Auto CarQuest PN ECE1033 because it was available
      • Installed LS3 1 BAR MAP and car acted better, but MAP data was still dead on HP Tuners logs; MAP levels were different numbers now
    • Figured out Lingenfelter Adapter Harness was incorrectly wired
      • On LS3 MAP side, Ground needs to be middle pin and Trigger Signal is outside pin
      • Swapped pins in the connector and rewrapped wiring loom
• Uploaded LS3 C5 tune
• Ran car to 120*F coolant temp and shut off
• Install tunnel plate
• Install headers back exhaust

 

January 4, 2025

• Install square exhaust hanger bushings
  • Originals were missing on one side and melted on the other
• Extend CAM sensor harness on Lingenfelter Convertor Box to allow mounting location near battery on firewall
• Proper soldering and heat shrink; rewrapped harness and loom
• Mount Lingenfelter Converter Box on unused threaded stud on firewall near battery
  • Drilled out one mounting hole and found nut to fit stud
• Create 10A fused ignition jumper from fuse box under hood for Lingenfelter Conversion Box for 12VDC power wire
  • Used fuse slot #19 ENGIGN1
  • Fuse jumper I purchased has one fuse for original slot in block and another for a jumper to whatever you need to use
• Proper solder and heat shrink to Lingenfelter Box harness; wrapped harness
• Ground Lingenfelter Conversion Box to ground stud on passenger side frame rail
• Wrapped ground and 12V wires with loom; routed around and under batter tray
• Clipped small slot in fuse block cover to allow 12VDC line to come through
• Clean up wiring looms on engine; route and tuck and ziptie
• Rerouted right rear ABS and tail light wiring harnesses away from passenger tailpipe
• Ziptied front crossmember wiring harnesses and looms
• Ziptied fan harness and connector
• Ziptied unused power steering rack magnasteer electrical connector and harness
  • Unused in this rack because magnasteer was not repairable
• Cranked and ran engine to 195*F coolant temp
  • Fan came on at 180* as tuned
  • Revved to 3000rpm several times
  • Engaged 1st gear and ran up to about 15mph to test clutch engagement

January 5, 2025

• Fill fuel to full to have both tanks equal weight for corner balance setup
• Adjust coilovers (refreshed by RE Suspension – DA Penske 7500 w 1000lb springs)
  • Compression (top)
    • All 4 corners: full clockwise stiff, -20 clicks counterclockwise (midrange)
  • Rebound (bottom)
    • Fronts: full clockwise stiff, -10 sweeps counterclockwise (midrange)
    • Rears: Full clockwise stiff, -12 sweeps counterclockwise (midrange/soft)
• Had to clearance right rear a-arm for adjuster
• Remove rear leaf ballast

January 11-12, 2025

• Install tailpipe exhaust gaskets
• Test fit Airaid Intake – did not fit, it was for a C6 Corvette
• Install OEM intake
• Zip tied radiator shroud
• Bled Brakes
• Install lower-to-upper intake vacuum hose
• Put 35psi in each tire
• Adjust Ride Height and Corner Balance
  • lots of notes on this, too many to paste here

January 18, 2025

• Install sway bars, front and rear
• Checked washers for spacing and free rotation and endlinks for pre-load
• Taped radiator shroud
• Install radiator screen
• Add trans fluid and topped off
• Add diff fluid and topped off
• Checked all fluids
• Ran car to operating temp, fan on at 180*-ish, temps settled at 199*-ish
• Drove car down street, operating in 1st, 2nd, and Reverse

January 26, 2025

• Uploaded email tune from PCM into car
• Brought coolant temp up to 190*
• Drove for several miles and data logged
• Emailed run log to PCM
• Transmission stuck in 3rd gear on first drive
  • Removed shifter boot, removed 4 base plate nuts and plate
  • Reset shifter position
  • Reinstalled base plate and boot

 

February 1-2, 2025

• Cut 6” silicon tube for throttle body to new K&N intake bridge
• Blocked off air tube and install holes in K&N filter
• Deleted MAF from K&N intake bridge filter setup
• Installed K&N air intake bridge and filter
• Drilled K&N air bridge and installed rubber grommet and GM IAT sensor
• Drilled K&N air bridge and installed rubber grommet and 90* brass 3/8” elbow for fresh air PCV
• Removed MAF connector from wiring harness
• Soldered in IAT connector
  • Tan and purple in wiring harness to white and black of IAT sensor
• Created hose from passenger valve cover to intake bridge for clean air PCV
• Uploaded latest email tune from PCM
• Four wheel alignment by David Farmer Racing
  • Adjusted thrust angles from and rear
  • 1/8” toe-in on the rear
  • 1/8” toe out on front
  • Camber locked by plates, no change
• Dyno break-in and monitoring at David Farmer Racing
  • Logged 2-3-4-5-6 gear runs on dyno to fill in LT Fuel Trim tables
  • Logged one 4th gear WOT-to-Redline: 473.79rwhp, going 16:1 lean
• Changed break-in oil to Mobile 5W-20, changed oil filter to Mobile 1 M-107A
• Added one bottle of Water Wetter to coolant tank

February 4, 2025

• Install new passenger halfshaft
  • Throwing grease while on dyno, boot was cut
  • O’Reilly’s had a GM part number unit for $100
• Install new Schroth window net
  • Old net was expired; HMS has 20x18.5” nets in stock for $100
• Discovered fire bottle expired December 2024

February 6, 2025

• Fire bottle recertification by RPX in Maiden, NC

February 8-9, 2025

• Installed fire bottle
• Built new front splitter
  • Disassembled old splitter
  • Power washed ACP street splitter “spacer”
  • Painted ACP street splitter “spacer”
  • Cut sheet of alumalite
  • Assembled splitter
• Fabricated new rear cradle bracket
• Installed splitter on car
• Installed and adjusted splitter rod lengths
• Installed ¼” aluminum c-channel trim
• Installed AMT titanium splitter scuffs
• Loaded car in trailer for PCM tune

February 12-14, 2025

• Dyno tune by PCM of NC
• Made 497rwhp and 484rwtq

 

February 15-16, 2025

• Shakedown at Carolina Motorsports Park with NASA-Southeast
• Saturday
  • Car felt good in warmup, no issues, throttle response good, shifter slightly notchy, cool suit cooler not working – decided to race it with no reserve
  • Thunder Qualifying – placed 1st in new GT Unlimited Class
  • Thunder Race 1 – placed 1st in GT and 1st in Thunder overall
• Sunday
  • Thunder Race 2 – rain race
    • Fan wiring caught fire on grid with 3 mins to go
    • Disconnected fan wiring and pulled fan fuse
    • Car would not start at 1 min to go, push started car out onto track
    • Started P2 in GT and P2 Thunder overall
    • Finished P1 in GT and 6th or 7th in Thunder overall
  • Thunder Race 3
    • Started P2 in GT and P2 in Thunder
    • Finished P1 in GT and Thunder

I have a few things to do to the car before racing at Roebling in Savannah in April, but the car is in good shape. The main thing now is to get it back on David Farmer's dyno and detune it for ST2 and ST3 trim.


Again, I hope these notes helps someone in the future. I spent a LOT of time searching the internet and texting people for a lot of the small things that people know but never talk about in a swap.

 

This is a great thread others could use as a veritable checklist. That is the heart of what the forum platform represents - shared knowledge easily referred to by someone, somewhere, 80 years from now when we're not around to answer questions.

 

Fantastic writeup. Thanks for taking the time to document your notes and share them publicly, including the most important part - the issues! I'm sure I will be referencing this in the future.

 

The idea to swap my Ls6 for a Ls3 is on my mind for a while, but after reading your post I’m totally discourage

 

There's a lot happening here that isn't directly correlated to the LS3 swap itself. Remember, this is a race car and it was doing race car things prior to said swap. His list of items and how he did it may not be directly applicable to you or someone who may want to do this in their street-driven C5Z. For me, I've been looking at this swap for a long time but, in all honesty, I think my top end power goal for a C5Z would be 650whp, which I feel is plenty possible with a worked over LS6 but, much easier to achieve with a proper LS3 swap--hell, you can get an LS3 N/A to make ~550whp, which to me, would be even more ideal than going boosted. That's really why I keep looking at LS3 swaps myself and probably why others do, too.