Has anybody run the GM LS2/LS7 ECU with the engine harness in a Cobra?

Welcome to the Forum Alffie.

The contact in the ECU won't handle the current demands of the thermo fan. You will need to run it via a relay. It'd be easy enough to wire a dash mounted switch in to trip the relay manually as well. I've been thinking about doing the same myself.

Cheers

ecu turns on a relay for each fan

what do u mean alfie ive done afew cobras anything can be made to work in any car if u try hard enough
ls2 and l76 have 2 harness to get everything for the engine to work

the 2nd harness is part of body harness which makes it difficult for most

i modify main engine harness and add in all the extra plugs and wiring and relays and fuses needed to make it a very simple wire up job

to do it the other way u have to buy the body harness which is worth over 800 bucks then u have to strip it down and modify it and add relays and stuff

ive got 4 on order so far

2 are just bought done

i never run a switch in dash for thermos

i dont care how smart u are u will one day forget to turn the fans on

i do run an overide switch but i never rely on the driver to remember to turn it on
trust me u will forget one day to turn it on hehehe

i also sell small fan control units these have a digital temp gauge and can turn on a fan at any temp from 70 to 100 and can be adjusted in afew seconds

they are a great small item they have water temp oil temp and volts gauge and a fan relay trigger no doghey wires in radiators
comes with 2 sensors which u fit into thermostat housing and your done


one day id like to start making premade full harnesses for cobras but to do a very nice sort of hidden job is hard without the body infront of you
plus price would not be cheap compared to other looms out there

but in the end it depends if u want a cheap loom which looks hideous
or an expensive loom that looks neat and tidy

maybe if i get some spare time i can start making them if demand was there

Sideshow, I reckon there's a good case for something in between. Since you're already doing the modified engine and body harness for LS2/L76, you could make wires long enough for computers mounted in the passenger footwell, then standard lengths for all wires from the rear of the vehicle to a fuse box also in the foot well. I reckon most people would have similar requirements there. The real problem will be what's behind the dash, which gauges, senders, etc.

Have you wired a Harrison Cobra yet?

yes id like to get into making full looms but problem is trying to get time to do it
do one big job a day pays much better than full rewires or making up full body looms

i will look into it though over the next few months

i have had a l76 and an ls2 loom here to wire up and i can compare the wiring lengths between the 2 and they seem similar

all cobra kits look similar to me i cant remember what the harrison is like

think i did a harrison at neil streetings workshop

or might have been afew years ago when i did my 2is ls1 or might have been the 4.6 ford quad cam i did in another but not sure

they are all the same to me when it comes to rewiring them

all ls1 ans ls2 and l76 std engine looms are long enoug to fit the ecu under the left hand dash kick panel area

by the time i wire up a body loom and then wire up the engine loom to plug into it price will be atleast 2g

ive seen looms where they use the holden fuseable links and holden relay fusebox unit but i think its bulky and messy

i now use the new micro relays for most stuff and anyhting with more load i use normal size relays so price goes up due to micro relays cost more
then u have the relay sockets
alot of people dont use sockets for relays

anyway ill look into it but for now im booked for 2 to 3 weeks

ill speak to my friend who helps me sometimes and maybe start making notes

if anyone is interested in maybe purchasing a full premade body loom suited to their engine let me know

i usually just buy the premade looms u buy from usa and make that fit to the cobra body cause they have very nice compact fuseboxes

Aussie
When you got your kit off Ian did you get his loom? Or did you make your own? My LS7 came with the ZO6 engine loom which doesnt have a T56 loom as part of it. I have managed to find new GM connecters for the T56 so I can wire it into the ECU. Do you know who Ian gets to do the ECUs as he wont tell me how did my ECU?

Sideshow I checked out your web site and found the immobliser. Can the reader read the key through a fiberglass dash? or does it need the key to be passed directly over the reader?

Hi Alffie,

I'm using an LS1 and I cut and shut a Commodore engine loom to get mine running. I made the rest of the loom up my self.

Speak to Plums here on the forum about your ECU programming. If he can't do it for you he'll certainly point you in the right direction. He did a great job of re programming mine and has done ECUs for quite a few on here.

There's only a couple of things the ECU needs from your T56. The reverse lock out solenoid wiring and the speed sensor. The ECU doesn't care about the reverse light switch so you can just wire that into your regular loom.

Cheers

Hi alfie, the reader can pass through a fiberglass dash.. have had them hidden behind VK commodore dashes and the like.. if it is behind a thicker piece then we can just make the reader stronger..

hope this helps

:3DSMILE:

Hi Mike. With the loom you made up, where did you get all the colour coded wires, connectors, etc that are required to make it up from scratch? I can only find those individual packs of connectors and rolls of wire at Bursons, Repco, etc. Trying to locate a source that sparkies might use, for instance, and not pay through the nose for it!

Cheers,
Paul

Hi Paul,

I started with one of those generic hot rod looms that go for about $300 and then gutted it of all the stuff I didn't need. I then made up my own relay loom and other sub looms using the left over cable.

Cheers

Sounds like a good idea Mike. Just looking at the EZ Wiring harnesses online. Do you know whether the 12 circuit harness will be enough? Thanks.

Hi Mike
Ian has already got my LS7 ECU tuned for the Cobra and had a mafless tune put in aswell. I just want to know what the computer has to be wired to and how I should wire up my gauges, either direct to the seners or from the ECU, Also did you plug the ECU straight in the pedal or do I need a BCM for the pedal.

Hi Alffie - do a search on LS1tech.com, Im sure you will find LS7 ECU pin outs on there, might be a good starting point at least.

Thats going to be a beast - Any background on your car and where it is at?

Cheers.
:)

I picked up the rolling chassis in may SN 3208. The engine and trans are in, had to move the T56 across 20mm to clear the handbrake bracket. used a VS radiator which only just clears the body, It took a lot of ginning around to fit the oil tank which only just fits. Doing the body work now, the seams arnt good the painter wasnt happy when he saw them! Once the paint is done I have to do the electrics fit the interior and do the side pipes and off to engineering I go. So far the engineer is happy with everything.

Hi Tenrocca
Did you get an ECU and loom from Ian? At $440 for the program he was the cheapest I could find. You can get ECUs from GM in the states for around $US190.
Hows you project going?

Which ECU are you using with the LS7?

My guages are all liquid filled mechanical Autometer guages as there is no real provision to get any readings from the factory senders connected to the ECU. All the signals for the factory guages are processed by the ECU and then sent as serial data to the BCM. The BCM then relays this data to the guage pod which displays the readings.

It's all done via OBD2 so in theory if you sourced a bunch of Aerotech OBD2 guages you could hook them all up to the OBD2 port and have each one set to display a different parameter. It's something I thought about doing but in the end I liked the simplicity of the mechanical guages.

Cheers

I think its a E38, Its the one with 2 connectors the same as the VE. Its a ZO6 computer out of the Corvette. Ian says he uses the VDO gauges and he wires them up to the ECU. The ZO6 LS7 ECU has all the sensers going idividually to the BCM which then sends them on to the instrement cluster. The ZO6 also has a control modual for the pedal pot which gos to the BCM then to the ECU. Things like the oil light dont go through the BCM. I got a ZO6 GM manual all 1500 pgs, which is a little complex for a novice cone head like me.
Geez the ZO6 has some electronics in it!! My Cobra has about a 100th of the electronics.

The E38 ecu is used on the Series 2 VZ (L76), and on all new VE's. The E40 (3 connectors) is used on the HSV LS2's and GTO. E38 is used on LS2 corvettes and the Z06, and alot of other GM cars in the US (not just gen3\4 engines - all sorts of things).....I think (disclaimer) :o

I haven't played with the new ECU setup or fly by wire. I'm more familiar with the VT-VY series ECUs. However I'm sure someone on here will have the info you need.

Cheers