car was stolen and they hacked up the wiring harness taking the engine and trans. what harnesses are available for the car?

it was originally a TPI harness that i had running my 383 HSR, now im thinking of going with carb. i know painless has kits but are there other brands out there?

the Painless kit im seeing is a 12 circuit basic kit... for like 350$! geez. dnt really feel like getting a stock wiring kit since they are really messy.

i just want to know my options.

 

It'd be a lot easier to just use a factory harness. Pick the one that's closest to your prefered engine management system and run with it.

 

For a carb you need so little wiring you could do it your self much cheaper

 

a factory harness for a TPI is not an option, since ripping one out and purchasing something that is as nasty as it is isnt worth it.

this is what i plan to do... im planning on going to a carb setup... reason is that EFI is too expensive at this point, and i will not be looking at this car as a daily driver (which it was with the 383) which is why i kept my compression at 9.8:1 and tuned it so i could drive it daily so the EFI was worth it. but ive come to the realization that u cant have nice things where im from so im building it for all out guts and performance on a budget.

ive thought about going LS1 but finding the engine/trans and harness/ECM for a good price is hard to do around here. many of the LS1s were destroyed in the "cash for clunkers" ordeal. if i were to find one however i would def consider it.

this is what ive got readily available to me lol... ive found a ford big block 460 complete engine and trans i believe for free! i havent had time to look at it but i will be able to this weekend. im not sure of the yr/condition but i think it was around the 1973 era. it very easy to make 500-600hp with these big blocks and equal if not more tq! the bottom ends can handle 600-700hp with stock components! but they dnt like to rev above 6000rpms lol which is perfect.

 

please details please!

 

if you're not going computer controlled on the carb, you can do away with anything on the passenger side harness, since its only going to the computer controls. if you've still got the 700r4, you'll need to figure out how you want to deal with the lockup, and depending on your year, you've got VATS to possibly deal with

 

yea i figued the pass side is all ECM, cars harness is originally a 87 so no VATS. lockup im unsure about... since i could go with a ford 460 big block the trans would be ford as well... soo lockup or nonlockup idk wat id go wit and how id do it... perhaps a lockup control kit from B&M or something.

carb would be old school... so id need everything to wire up the Altenator, starter, distributer, coil, fans, etc. but how do i keep the interior wiring the same and just convert the engine bay to carb?

 

does anyone kno what this is? its on the firewall by the brake booster and it has 2 large weather pack connectors going into it. the wires go into the bundle that go into the firewall block/connector that routes the wires to the fuse panel under the dash. i just dnt know what this box controls.

on a side note... most of the wiring for the headlights horn are still there... mostly just the ECM wires are gone, as well as the coil/distributer/starter/cooling fans etc.

 

headlight module. was wondering the same thing a couple months ago

 

think i figured it out... think its the headlight motor/headlight box.

EDIT:haha guess i was right.

 

If you've still got most of the wires to the C100 (bulkhead near the booster) then you're set for a carb harness. Just lengthen a few critical wires

Read over the 3rd gen prep thread

87's run the fuel pump wire through the C207 near the ECM, so all the wires on that side of the car cannot be removed. Several other critical functions are there too like fan control

Congrats on getting the car back. Such a shame to see something so cool get boosted. You may want to look over the anti-theft measures people come up with in this forum to keep it from happening again

 

... From the C207, the fuel pump wire crosses over to the C208 by the bulkhead connector at terminal P, a tan/white wire. All he needs to do is to run a wire from X connector (whichever one he wants, I used G4 for the late thirdgen harness) in the C100 bulkhead connector to that wire. However, if he's going carbed, he's probably going to do away with the electric fuel pump and run a mechanical, seeing as how he wants to run a Ford engine.

The fan control can be rewired easily enough with an add-on switch through the radiator or something along those lines. However, you may want to switch to the mechanical speedometer, (if you have the electric) because the VSS signal wires DO run through the C207 from the buffer to the instrument panel. Other than those 2-3 wires, everything else coming through the pass-through behind the pass side kick panel can probably be deleted if EFI is being removed.

 

Actually the speedo is ran direct from the buffer box which is fed from the C100. The buffer box outputs a signal through the C207 to feed the ECM

The fuel/fan pins were examples, there are other important features over there that need to be thought through

 

C221 (the small six pin connector over there that isn't part of the cruise control harness) terminal C is just about the only wire needing to be retained as that powers the coolant fan relay coil and alternator voltage regulator from the fuse panel (I'd run that through C100 G7, which powers the alt, as the fan relay is right there and the wire is spliced later in the harness anyways). Going Ford, he's probably going to be deleting the ignition control, emissions control, ESC, engine data sensors, fuel injector wiring, and anything to do with the 700R4 transmission (probably going with a C6 or other trans) and its electronic controls. All of which run on that side. The only wire from the C207 needing to be retained is in slot M, the ground wire to G112, and that can be grounded anywhere. No need to keep anything on that side. Everything else important can be run off of the C100 (ignition, starter, VSS for speedo signal, indicator lights, exterior lights).

 

you are correct! its a 460 BBF but its been bored and stroked to 521cuin . also im going with a C6 trans prob since i got the ford 460 and trans for free... and the C6 will hold up to the power i plan to make with the 521... should be in the 650hp range hopefully Natrially aspirated.

Ok so this is what ive come up with...

I made some motor mounts for the motor and dropped them on the stock type poly motor mount clamshells... IT FIT! but the engine is so far foward that the crank snout/crank pully/harmonic balancer will hit the front sway bar/wonderbar. the ford 460 alot longer in the front than a chevy. but thats gotta be pushed back like 3" but then i have issues with the oil pan hitting the idler arm. anyways back to the electronics.

I plan to run a rear mount batt... will be NHRA legal too. I will run my own fuel pump harness using 10gauge wire with a dedicated 40amp bosch relay to get max volts to the stock in take walbro 255lph high pressure pump. YES! i will keep the EFI pump bc i can run a bypass type regulator to give me the fuel pressure i need. I will also purchase a dual fan relay/wire harness to power my fans off a 12V ignition source with thermal switch.

the things i need to make are the IGNITION and alternator charging harness. the wiring on the pass side will be kept for the headlights/exterior lighting etc. i have the ignition wires from what i can tell (large red wire, and pink/purple?) I want to run a HEI type ignition perhaps with a vacumm advance. How do i wire the HEI with the stock wiring?

Ok the speedo will be junked/sold. I will most likely be running the C6 but i want that overdrive gear for highway but idk what ive decided on. the C6/460 i have was out of a 76 thunderbird so its a mechanical speedo... i will swap it out for the autometer hall effect electric speedo sensor. I will then hook that into the stewart warner speedo that i can calibrate for the setup i have. I will like to use the stock tach and other gauges, so the sending units will have to purchased again and lengthen the stock sender wires.

I cant use the stock cruise control correct? since it incorporates the ECM?

 

Alternator, ignition, and exterior lights all run through the C100 bulkhead connector on the DRIVER'S side, by the brake booster. The larger connector there is the engine harness, the smaller one the lights and horns and what not.

To retain the HEI system (why not go with MSD or something?), all you need is the PINK and WHITE wires off of the coil, one for power (pink) and the other for the tachometer (white). Both of these wires run through the C100. You will need a vacuum advance dizzy, as ECM control will obviously be deleted.

Cruise control is a completely separate system with its own wiring harness. The only computer in the system is the black box under the pass side dash. However, you will need to make sure that this gets the proper speed input from the converter box for it to work right (2000 PPM, IIRC, may be 4000).

 

i figured out that the headlights have there own box, ive isolated the wires that go behind the engine which are my ignition wires etc. so all i need is the large pink wire for the HEI? did the white tach wire have a large grey connector? the wire is so dirty that it looks creme kinda but it has a large grey connector on it.

when u say MSD u mean a 6-AL ignition box or something right? I figured that i would run some kinda ignition box but im unsure if its neccessary. this engine is being done on a budget, cheap rotating kit, cheap aluminum heads, cheap hyd flat tappet cam, cheap intake, cheap make my own engine harness. I had too much money in the engine that was stolen. I figured with the mild RPM range of the 460/521 i would be limited to 6000rpms before it would run outa steam and that i could get away with a HEI distributer puttin out 45,000V.

so theres a black box on the pass side by the ECM for the cruise control? what does the converter box look like?

 

Yes, the tach wire at the coil has a gray connector on it, used for troubleshooting the ignition system in the engine bay. It will be in the same gray coil connector as the pink wire.

Didn't know your budget... But you can find a cheap complete MSD 6 system on eBay or somewhere if you look hard enough.

If you have the Formula in your sig, and it's a post-86 with a gauges cluster (no idiot lights), all you need is the black box under the dash panel by the passenger's knees, and the yellow VSS buffer box (that you can connect both an aftermarket speedo and speed sensor for the C6 trans to, BTW) that is attached to the ECM bracket, on the dashboard side. That's all you need for the cruise control system.

 

the grey connector on the tach wire that im talking about is not the same as the one that connected to the coil. this is a single weather pack connector (not the double interlocking coil connector). see pic.

I have a large pink and red wire, (see pic) the pink is the 12v so then wats the red wire? the harness was cut off completely when they stole the engine so i have no connectors or ideas to where the wires went.

I was actually thinking of the pertronix ignition box... its the only box with multiple sparks until redline, not to mention more ignition voltage and equal power consumption of the MSD units, also has a digitial rev limiter built in etc... still it goes for 315$ lol.

The formula is a 87, its with the stock 350TPI harness and ECM, it has full gauges and no idiot lights like the V6 models. The problem here is that those ****** who stole my engine/trans took the ECM which had the black and yellow boxes attached to it... so basically my cruise control is useless... great.

THe the is that the C6 has a cable speedo, gona upgrade to the autometere hall effect electric speedo sender... then run a stewart warner 5" indash speedo... so i dnt need the buffer anyway since the stewart warner will work with all senders.

the pic shows the grey connector im talking about, it also shows the large purple wire, large red wire, large pink wire and a smaller red wire. this is coming from the driver side wire bundle C100 bulkhead. (which is the large connector farthers to the driver side in the C100 bulkhead) what wires are the purple, red, smaller red?

 

Hey, now. My 87 base V6 has the full gauge cluster as well.

It's possible that the thieves left the cruise control box but ripped you of the ECM and VSS buffer. The cruise box is behind the panel under the map pocket (not the big black one down by the feet). Or it should be.

In that wire bundle in the pic, the red is power from somewhere and to somewhere, the purple is probably the starter solenoid switch wire, the pink the ignition wire, and the smaller red may power another device (hard to tell without knowing exactly what terminals in the C100 they come from). And yes, that gray connector is the tach wire. Like I said, that connector was put there for engine bay based diagnosis.

 

so ive started the wiring harness... lol.

I figured out at one of the red large gauge wires is the batt power for the fuse panel in the car (lights come on inside when door opens). the other large red wire i havent figured out. Everyone says the pink wire is for the ignition... is this a 12v switched source for the coil? I remember this being on the grey connector for the stock remote mount coil. Now where do i connect this too on say... a MSD street fire box for a magnetic pickup distributer?

Ive cut the wire wire (tach)right behing the instrament cluster plug and spliced in the grey wire off the MSD street fire box... so if there was a tach filter i couldnt see its def bypassed.

So where do i connect the pink wire too? and wat about the other large red wire? Im assuming the purple wire is from the igntion/neutral safety switch to the starter.

Ive also started my plan to duplicate the racetronix "hotwire" fuel pump harness, got some 10gauge wire, 30amp relay but going to have to run it off the ignition somehow to activate.

 

Pink wires are almost always ignition controlled power sources. Connect it either to the positive side of the coil or the ignition input on the MSD box.

Does the red wire begin with a large or a small ring terminal?

 

Not to steal this thread , but I have one question. 1990 Iroc does it also have a buffer box? If so where is it located? Thanks

 

One large red feeds the fuseblock/headlights. Other is IGN switch on the column and other dash functions. Both are required

Rule of thumb for GM wiring:
Red - Battery 12v constant Some fusible link, some not
Orange - Fused 12v constant
Pink - Fused 12v switched
Blk - Primary ground
Blk/Wht - Component ground

There are exceptions, but this should get you going for a while

A 90 IROC will be SD TPI so it wont have a buffer box. TBI and MAF TPI/V6 cars got them

 

Summit sells Painless wire harnesses for 86-92 TPI cars. Here's a link...if you're interested.

http://www.summitracing.com/parts/PRF-60102/

 

the large red wire does not have a ring terminal... the wires were cut about 3ft after the large firewall connector on the driver side. So i should attach the pink wire to the MSD box 12v switch wire? Im running the MSD box so the MSD box charges and fires the coil... so the only 2 wires going to the coil are the msd boxs.

heres the diagram that im following. basically the MSD box charges/fires the coil and i have no control module. the MSD box gets the signal from the magnetic pickup from the distributer. So i only have to hook up a 12v constant and a 12v switched wire and im ready to do. as u can see in the diagram.

 

So im connecting both large gauge red wires to a 12v constant source like the batt?

 

500$ for a harness that i wont use at all bc im not running EFI. switching to carb means very little wiring.

 

anyone know what this is?

pulled it out behind the ALDL port... both the ALDL and this box were connected together with a metal bracket that mounts the ALDL port under the dash.

it has a large blue "buffer" type box, a white plastic relay cover kinda thing, and 2 large "flasher" relays etc.

just need to know if i have to keep it. i had to tear it outa the way so i could relocate the gas pedal.

 

Small cyl is turn signal flasher

Not sure of the relay

Blue box is chime when you leave the key in or forget to turn off the headlights

 

It's called the convienence center... Bottom line is that you NEED it. The relay is the horn relay, there may be 2 flashers in it (turn signals and 4-ways), and the blue box is for the chimes as said above, for when the key is left in the ignition or the lights are left on when the engine is stopped.