Phase I: 3rd Gen LS1/T56 swap

Phase I

Ls1/T56 swap into a 3rd gen Camaro

Here is my DIY on my LS1/T56 swap, there are a few different ways to do things involved in this swap so what I did is not gospel, it is merely my originality so anyone tackling this swap please keep an open mind, have fun and be creative. Any and all information can be found on the web, the Internet is an unlimited resource; use it to your advantage. A lot of the pix are mine from my swap, others I have snipped from other posters including some wiring diagrams.

First things first, the things you will need:

  • 98-02 LS1/LS6 motor out of a Camaro/Firebird or Corvette, preferably a Camaro/Firebird as there are a few differences in accessories.

  • 98-02 T56

  • 98-02 computer & engine wiring harness (scroll down for more info)

  • LS1 swap headers or stock exhaust manifolds, I used Stainless Works 1 ¾ primary long tube headers, tig welded stainless steel, very awesome quality! Click for pics and info on Headers

  • LS1 swap motor mounts, Hawks sells all the necessary swap parts, they have an entire section dedicated to LSx swap parts. Click for pics and info on motor mounts LS1 motor mounts on the block are actually located 2.5 inches further forward than on a Gen I or Gen II small block. You can see in the pics below I have an aftermarket k-member and the LS1 motor mounts are located further back than the norm. I took some plate steel, extended the k-member mount back and then welded a gusset behind it. On a stock k-member all that is needed is to re-drill new holes to relocate it or you can buy the aftermarket LSx k-member for this swap.

  • T56 cross member, Spohn Performance, BMR and a few other companies sell these. You can either get just the cross member or a complete torque arm/ cross member package which relocates the torque arm from the transmission to the cross member. I like homemade pieces anytime I can make them or buy them, I used a homemade cross member which allowed me to pass my exhaust thru the cross member keeping it tucked up high, very nice since my car is lowered 2 inches.The mechanical swap is actually very simple and virtually bolt-in. The tricky part is wiring, it can be as difficult as you want to make it. Here are a few pix of the engine when delivered and then mocked up in the car then I will move into the electrical side of the swap.

    98’ LS1/T56 & 99’ LS1/T56
    The 98’ motor had a broken rod and was not used obviously, unfortunately I found out the hard way when I started it up. I got the 99’ motor, cleaned it up, gave it a quick tear down, clean up and heads/cam swap which I will go over in a different DIY thread for anyone that is interested.
    98 & 99 LS1 / T56 motors
    http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/99ls13.jpg
    98 motor mocked up for fitment
    http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/98ls1garbage12.jpg
    http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/98ls1garbage13.jpg

    LS1 engine harness wiring

    As I said above, the wiring for this swap is as hard as you want to make it. In reality you only need five +12v (2 constant, 3 ignition) wires hooked up to actually start the motor. In addition to those wires are wiring in your gauges and that for the most part is it.
    Parts needed for this step:
    ·LS1 wiring harness & computer
    ·4 relays (fuel, computer, injectors and coil packs)
    ·extra wire, (10, 12, 14 & 16 gauge)
    ·an assortment of connectors mostly pole and spade connectors
    ·A soldering gun and shrink sleeving

    First thing I did was lay out the harness, connect every connector you can to the motor and transmission that you can.

    Harness laid out on the floor
    http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/Picture034.jpg

    http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/98ls1garbage30.jpg

    Next the re-wiring. Some people get the whole engine and chassis harness for this swap, others buy an aftermarket harness from Painless Wiring, Howell, Speartech, etc. For these harnesses you have to have an original TPI 3rd gen car, these harness are made to adapt into the stock harnesses, very simple plug and play but definitely not cheap. The cheap route is to do the wiring yourself.

    There are 5 connectors on this harness that are not connected, these are the ones that need to be spliced into your exsisting chassis harness, interior harness, or wired to relays.

    99 LS1 PCM to Dash Harness

White (220) Plug
A TAN Oil Pressure
B GRY PCM 32 Clutch Anticipate Switch Signal
C PNK C105-B IGN Power for TCC Stop Lamp Switch
D PPL PCM 33 TCC/Cruse Brake Switch
E BLK/WHT Ground
H ORN/BLK PCM 34 PNP Switch Signal
J YEL/BLK Low Coolant Indicator
K DK GRN/WHT PCM 50 VSS Output

Blue (230) Plug
A GRY PCM 46 5V Feed (Fuel tank pressure)
B Brown w/Stripe PCM 25 MIL Lamp Control
C WHT PCM 45 EVAP Canister Vent Valve Control
E Blue PCM 55 Theft Deterrent Fuel Enable
F DK GRN/WHT PCM 17 A/C Request
G GRY PCM 23 Fuel Ground
H DK GRN PCM 64 Fuel Tank Pressure
J PPL PCM 54 Fuel Level Input
K DK GRN PCM 58 Serial Data (Class 2)

99 LS1 PCM to Front Harness

Large Plug C100 Plug
A PNK Hot in Run and Start (IGN/INJ Bank 1 15A)
B DK GRN/WHT PCM 43 A/C Clutch Relay Control
C DK GRN PCM 18 A/C Clutch Status
D GRY TPS +5v to TCS
E DK BLU TPS signal to TCS
G PNK Hot with IGN 1 Relay Engaged (Tranny/EGR 15A)
H DK BLU PCM 33 Cooling Fan 2 and 3 Relay Control
J DK GRN PCM 42 Cooling Fan 1 Relay Control
K BLK TPS sensor low to TCS

C101 Plug
A YEL/BLK Low Coolant Sensor
B PNK Hot in Run and Start (IGN/INJ Bank 2 15A)
C BRN PCM 36 Air Pump Relay Control
D DK GRN/WHT PCM 9 Fuel Pump Relay Control
E PNK/BLK PCM 19 Ignition Positive Voltage for PCM
G ORN PCM 57 Battery Positive Voltage for PCM
H BLK/WHT Ground
K GRY/BLK PCM 53 TCS Spark Retard Signal to Brake Control Module

C105 Plug
B PNK Hot with IGN 1 Relay Engaged (TCC Stop Lamp Switch/MAF/O2 20A)
D DK GRN PCM 37 Cruise Control Inhibit
F WHT PCM 13 Cruise Engaged Signal
G WHT PCM 10 Tach out to Brake Control Module
H PPL PCM 4 AIR Solenoid Relay Control

These are all of the pins/wires I did not use:
220- E,H,J,K
230- A,C,F,G,H,J
C100- B,C,D,E,K
C101- A,C,K
C105- D,F,H

If you take your time its very straight forward, one wire at a time, keep them organized and solder everything. Using distribution blocks and terminal blocks really make for a clean organized install. Here’s a picture of my distribution block under my dash, I ran +12v constant, +12v ignition, and a few other misc wires.

Distribution Block

http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/IROCLS1121.jpg

Terminal Block – Good for connecting +12v from starter so you don’t end up with a buildup of wires.
http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/555-10521_2.jpg

LS1 Fuel System

Some use their stock 3rd gen gas tank and stock lines, others choose to use the 4th gen gas tank whether it’s the 98 metal tank or the 99+ platic tank. I opted for the plastic 4th gen tank. The charcoal canister on the tank can be removed if not using emissions, the stock pump is fine for stock and lightly modded builds. I chose to upgrade to a Racetronix 255lph pump and hot wire kit because as most people know I can not leave anything stock.

Racetronix Fuel Pump & Hot wire kit

http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/s260_large.jpg

For the fuel line I used –8AN feel line from the tank, and –6AN return line from my Aeromotive regulator. The LS1 fuel system is a returnless system, if you plan on making any amount of real power I’d recommend making it a return style system. Heres a pic of a modified gas tank, I did it the same way except I used –AN lines and fittings.

Modified 2001 gas tank

http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/Picture039.jpg

There are a few other misc pieces needed but its moreso going to autoparts stores and hunting down coolant lines and small goodies. Here are some pics of the finished product.

http://img.photobucket.com/albums/v229/orangeiroc/IROCLS1110-1.jpg
http://img.photobucket.com/albums/v229/orangeiroc/IROCLS1111-1.jpg
http://img.photobucket.com/albums/v229/orangeiroc/IROCLS1113-1.jpg
http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/cruisin053-1.jpg
http://img.photobucket.com/albums/v229/orangeiroc/LS1%20swap%20pix/cruisin054.jpg

what a beautiful swap.

Clean swap and nice job on the details dude !!!

that is sooooo sexy, super clean…
I would be very proud if I was you, nice work =).

Although, i do know that f-bods with ls1’s have the pcm buried under the cowl on the left side (passenger) side of the car… which is why i am figuring that thats why you placed the pcm where you did, my question to you is, is it safe there?? and if not, should you extend the harness into the cabin??

but forget my nick-picking… very nice swap, I’m jelouse… =)

Wow nice writeup.

Vandit, its not buired on 4th gens. Alot of other GMs have it in the open like that, its fine.

awesome writeup mike :tup:

this is why you’re the manliest man around. good write up!

thanks =)

once again, very well done :tup:

nicely done. :tup:

i hate you mike.

jk ilu.

very nice :slight_smile:

Nice writeup!

:tup: nicely done

:tup:

nice swap and writeup. looks beautiful in there.

Thanks yall, it was alot of work but oh so worth it. Hopefully along the line this writeup will help somebody else out, i know i spent some long nights online searching for answers and every little bit helps.

Stay tuned for Phase II heads/cam swap + bolt ons, Phase III 4th gen interior swap, and Phase IV snky snky :carnut:

As I was reading, I was like “why not just swap an old school 350?”

But now seeing it, Wow…just Wow, Thats CLEAN.

It looks awesome, plus it fits under the stock hood.

Good Work. Great Writeup

Sweet writeup. I love 3rd gen’s with LS1/T56 swaps.

There are a bunch of reasons, i originally had an old school 383, carb setup, lot of nitrous, it was pretty badass. 550hp NA and 800hp on the 250 shot, 10 miles/gallon on the street, huge cam which made it very obnoxious to drive, th400 transmission with 4.10s in the rear really made it get up and go however 60mph on the street was like 3500rpm, very annoying.

The LS1 has a superior head design, my 5.3L ported heads flowed 312cfm at .600 lift, my old AFRs on the 383 fully cnc’d flowed 297cfm, and the 5.3s were half the price of the AFRs. With that said i can get away with alot smaller more reliable cam, the LS1 had a hydraulic roller 233/239 duration, .598/.603 lift, 112lsa, simply slap the cam in, adjust the rockers and go cruise… The 383 had a big solid roller cam 254/260 duration, .630ish lift on a 110lsa, with this you had to check and adjust the valves maybe once ever few weeks, pretty annoying maintnance. On top of that my LS1 was pulling about 25mpg with the T56 and 4.10s, as opposed to the 10mpg of the 383 i mentioned above. Power wise i honestly believe NA vs NA the LS1 would have edged out the 383, it suprised me and on the 125 shot it felt pretty retarded. :tup: cant wait to up the ante this season.

I can go on and on about the pro’s and con’s, but it really comes down to technology, gotta keep up with the times and like said above, its just to perty :wink: