New and need gen lll ls1 swap help!

**MontanaKid** · 05-17-2014, 06:54 PM

Have a 05 cts and 04 ls1 with t56 transmission out of a gto can someone please point me in the right direction regarding wiring.

**Firebirdjones** · 05-19-2014, 10:40 AM

I've done it 2 ways. Cut, splice and solder a harness yourself. It's time consuming and a schematic is needed.

After a few I started buying them done. I didn't like the idea of playing with 15 year old brittle harnesses anymore that might be a concern later down the road. Plus I have gotten so busy I just don't have the time to spend doing it anymore.

Plenty of vendors to buy from, most of us here could probably rattle off a book of suggestions. Personally I use Howell Engine Development out of Michigan. I've been using them since about 1998 and their service has always been top notch. You get brand new high quality wire (not cheap chinese wire or an old harness that's been hacked) It's all labeled plug and play and comes with relays and fuse box, and they'll add any options you desire for any car and any placement of the PCM. You tell them what you have and where you want the PCM and they make the harness perfectly to reach everything. Also great tech support if you have questions.

**MontanaKid** · 05-20-2014, 11:12 AM

Originally Posted by Firebirdjones

I've done it 2 ways. Cut, splice and solder a harness yourself. It's time consuming and a schematic is needed.

After a few I started buying them done. I didn't like the idea of playing with 15 year old brittle harnesses anymore that might be a concern later down the road. Plus I have gotten so busy I just don't have the time to spend doing it anymore.

Plenty of vendors to buy from, most of us here could probably rattle off a book of suggestions. Personally I use Howell Engine Development out of Michigan. I've been using them since about 1998 and their service has always been top notch. You get brand new high quality wire (not cheap chinese wire or an old harness that's been hacked) It's all labeled plug and play and comes with relays and fuse box, and they'll add any options you desire for any car and any placement of the PCM. You tell them what you have and where you want the PCM and they make the harness perfectly to reach everything. Also great tech support if you have questions.

Thanks! I will look into getting a harness. I feel like it would save me a lot of time.