After a couple of years of haveing most all the stuff and no time to put it together I took my Z to a friend to have him do the work.
He got the motor, tranny and 3rd gen Moser 9" in the car, but some of the wiring plugs don't fit.
I bought the harness from a board member. It's a 99 Ls1 harness that he had redone by Speartech to work in a LT1 car. He had it working in his 97 T/A with an LS1 motor.
I basicly have an iron block LS3 motor. 01 truck block and crank. LS3 heads, intake fuel rails and injectors. Custom cam, headers and after market T/B.
The injector plugs don't fit the injectors. The sencer/modgel on the left side of the T/B doesn't connect.
If you've done the LS3 into an LT1, I could sure use your help.
Thanks,
Rob

 

That is not an LS3. That is a LQ4 or LQ9. If it's stock it's a 24x Crank.

Sounds like you have a Gen III Harness, take a pic of the Throttle Body. You probably have EV6 Injectors too.

 

I have that exact set up. The injectors are EV6 and you need to buy the convertors here http://www.summitracing.com/parts/FMS-M-14464-A8 . I need to know what t-body you are using/picture to figure that part out.

 

No It's not an LS3, It's an LQ4 bored .065, with the lengthened rods, GM ported LS3 heads, L76/Ls3 intake, fuel rails and injectors. It doesn't have the 58X relucker wheel crank.
I was just trying to say that it's the same bore and stroke with the same heads, intake, fuel rails and injectors as an LS3.
The harness is a 1999 LS1 harness. I don't know rather that's a Gen III harness, or not. I'm not up on all the differences in these motors. I'm more of an old school small block Chevy guy. I'll have to go down to were the car is to get some pics, it's about 10 miles away.
As for the injector adapters. Are they to adapt LS3 injectors to a LS1 harness?
Just checking before I order them.
Thanks,
Rob

 

Yes LS1's used the EV1 injectors and the newer LS3's used the EV6 so to make the harness work on a drop in LS3 you just need those adaptors

 

It's a GenIII Setup that you have, with a GenIV Topend..not tryin to confuse you on it, it's just some of them components are need-to-know with the wiring. The Harness should work after you get the adapters. Put a pic of the Throttle Body up if you can..

Who did the .065 over-bore..that's pushin it on a 6.0l Block..

 

im doing an lt1 to lq4 swap myself.
theres a website that has all the plugs you need to adapt.
ill have to go find the old pm, that had the link in there for you