modifying 4.8 vortec wire harness need help.......

[jglz67]

Dropping the motor in my 67 already, got told I need to modify thee wire harness but clueless on wat to do anyone have a diagram or can tell me exactly wat to do...

[BADSAM]

Go check out LS1tech website, I understand you can get everything you need there. There is also a good writeup in the FAQ that mentions the wiring stuff. It might be called a 5.3 swap on the cheap or something.

Goodluck.

[kamikazekyle05]

I went to lt1swap.com and got the pinouts for my harness, ive printed them out and went down each pin to see if i needed it or not

[brad_man_72]

wait 4 me performance will hack up your harness and tune with free unlimited retunes for $360. i sent mine off yesterday. they eliminate the vats, not just some added box like most.

[jglz67]

cool thanks hopefully i get it done pretty quick i want the truck running already... what do yall plan on doing about the gauges, can we use the new a/c system?

[72 SHORTBED 7.0]

Here you go

http://www.ls1tech.com/forums/conver...shortstep.html

http://67-72chevytrucks.com/vboard/s...d.php?t=244448

[brad_man_72]

gauges, you have to have the comp reprogrammed to sent out a v-8 tach signal, you can drill and tap plate above oil filter to make oil gauge work, rt head near the rear their is a plug you can remove redrill and tap for temp sending unit.
if using a transmission that doesnt have a speedo cable you need an eletronic speedometer (definatly cheapest and easiest fix, but not the only way to do this)
im putting an eletronic speedo behind my factory gauge face and needle. im thinking a 94ish s-10 speedo will "work"

[kamikazekyle05]

Originally Posted by brad_man_72

im putting an eletronic speedo behind my factory gauge face and needle. im thinking a 94ish s-10 speedo will "work"

Id like to see and hear more about this

[68 short step]

Originally Posted by brad_man_72

gauges, you have to have the comp reprogrammed to sent out a v-8 tach signal,"

also most aftermarket tachs have a switch/s to make the tach read 4/6/8 cyl. you can simply put the tach into 4cyl. mode and it'll read accurate, w/out changeing the tach output of the PCM.

[brad_man_72]

Originally Posted by kamikazekyle05

Id like to see and hear more about this

ill be sure to take lots of pics, and if i get it to work ill post up a how to. i think i heard about somebody else on the board doing something simmilar.

[boostat4500]

Another option for the oil pressure gauge is to just use the stock hole behind the manifold. The PCM doesn't need the stock sending unit signal. Adapter bungs are also available for the temp sensor if you don't want to drill and tap.

[Big Port Jimmy 6]

Originally Posted by boostat4500

Another option for the oil pressure gauge is to just use the stock hole behind the manifold. The PCM doesn't need the stock sending unit signal. Adapter bungs are also available for the temp sensor if you don't want to drill and tap.

You have to make an adapter though the LS oil sender seals with a gasket and straight metric thread the "truck" sender will be pipe.

[glock35ipsc]

Although it's an older thread, I'm gonna move it to the LS swap area.