Need help ordering an engine ECM and Harness.

[GRNOVA]

Ok Guys, I am ready to start looking at what to order for my engine harness. What do I look for when ordering my harness and what info do I tell them. Here is what I have so far:

97-04
24x reluctor wheel
I want to run 12-17 psi of boost
running 60lb injectors
DBW throttle body from 99 Corvette (90mm)
Cam sensor at rear of engine
4l80e transmission w/ paddle shifter



I have a LS2 w/ Kenne Bell 2.8LHO SC
is there anything I need to add to the Harness?
https://static1.pt-content.com/images/noimg.gif

[meenaggie]

Some extra things I can think of are (1) how long you want the harness (or rather where you plan to mount the ecm), (2) specify just one O2 sensor per side (no post cat sensors for emissions, right?), (3) coil type, (4) delete factory security and emissions stuff and some other stuff, (5) one ecm for engine / trans (should be possible) or separate controller for trans. For a nice custom harness you can give Speartech a call. They get a lot of referals on this board.

[GRNOVA]

Yes just 2 O2 sensors How would I know what stuff to delete and what to keep? I will be using a paddle shifter so I think I will need two separate controllers one for trans and one for engine. Is there a special ECM I should look for with a 24x reluctor wheel? Thanks for the response Meenaggie

[garys 68]

Here's a good place to start your homework.
http://www.lt1swap.com/programming.htm
If you're looking to buy a stock harness/ecu and modify yourself, pretty much everything you'll need to know there.
I would suggest a 411 ecu, it's widely available and works with DBW.
You'll need a DBW harness, TAC, and pedal that works with that TB. Best bet is to look for a 99 vette harness.

[Mike Norris]

As mentioned by meanaggie, give John at Speartech a call. It is good to do your homework ahead of time, but he is good enough to ask all of the correct questions when it comes to building a custom harness. For what you have going it should all be straight forward and the only questionable item will be running the 4L80E with the 99 Vette ECM, but John will know if it can be done and do it it if possible.

From there, tuning the vehicle with a 2bar OS with HP Tuners should work just fine.

Hope this helps.

Mike Norris

[GRNOVA]

Thanks Mike,

I will contacting you when the time comes. As far as John at Speartech I will call him on Monday!

[meenaggie]

Since you are going with a paddle shifter I think most will recommend a separate controller for the trans. This should also make your engine ECM selection more straight forward as well (no need to find one computer that can do both engine and trans). I would recommend an aftermarket stand alone trans controller. You can with with one of the combos from TCI (their TCU, harness and paddle shifter) or a Compushift controller and paddle shifter from a company like Twist Machine. Twist Machine is a forum sponsor (look for orange banner to right) and will provide excellent tech support and help answer questions to get you moving in the right direction. Twist Machine has posted lots of info in the auto trans forum on this topic.

[GRNOVA]

Thanks to John at SPEARTECH!

https://static1.pt-content.com/images/pt/2011/02/DSCN0858-1.jpg

[CarlC]

John does nice work. Is the ECM from a 'vette or from somethink like an '05 Silverado? If memory serves the ECM in that model supports DBW and is 24x.

Did Speartech provide a get-it-started tune? If so, was it programed for a 3bar MAP sensor? Which sensor are you using?

[GRNOVA]

was it programed for a 3bar MAP sensor? Which sensor are you using?

I am not sure I told him I was going to run 12-17 psi of boost? I will have to call Monday, Good question.