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Project: Dirty South (K5)

The engine swap creates some new questions in my wiring research. Apparently, the LE9 305 from the factory had an "electronic spark control" module. This was a closed-loop system that controlled detonation by modifying advance and then returning control to the "EST" or electronic spark timing distributor. EST distributors did not have vacuum advance. It worked from two sensors, a piezoelectric knock sensor on the passenger side of the block, (which is also present on this 350, curiously) and a vacuum switch on the firewall that provided a signal at throttle tip-in to retard timing to reduce knock - this vacuum switch is still left over on my firewall. Inside the cab, the ESC module itself was supposed to be mounted on the brake pedal bracket and it is gone. Someone bothered to hook up the knock sensor on this 350 and to hook up the harness to the vacuum switch, but not a vacuum line.

My '86 had an LE9 305ci, and did have the ESC/EST. It also had vacuum advance. From my understanding, the system exists only to retard ignition timing, not "advance" it to a pre-set physical limit.

My ESC module (and AFAIK all of them) is mounted behind the glovebox.

Now, here's where things get weird. According to the shop manual, only California rigs had an ECM and I did remove one from above the glove box in this rig. However, the original 305 engine VIN code (H) for this truck is wrong for a California (F) engine (yay CA emissions). Further, if you had an ECM, you didn't have vacuum advance, which really tells me nothing here since this is a swapped engine. The distributor on the 350 is a vacuum-advance HEI unit that does not have EST ("electronic spark timing", which would be signified by a 4-prong connector coming out of the distributor, with brown, black, white and green wire leads to connect to the ECM).

See above about the location of the ESC--exactly where the Cali trucks supposedly had an ECM. Furthermore, mine's not a Cali truck, but the closet wiring diagram I could find that matched was in fact, a Cali V6 truck... :confused: :confused: :confused:

So, how does a rig that does not have a California VIN have what appears to have been an ECM?

See above again, LOL...

I'm interested to see where this thread goes. I also had TCC. It was unfortunately eliminated during an engine fire. :crazy: I have some alternate method of lockup installed via a Tranny shop.

Oh yeah... I swapped in a crate 350 as well, which I don't even know if it has a knock sensor. If so, it does nothing now. The ESC wiring was also toasted in the fire. Since I was no longer running a 305 and didn't need the knock protection, I hacked the HEI to make it function as an older unit would, with a single-wire hookup. I can provide the details of my FACTORY APPROVED HEI mod if you're interested (released in a service bulletin years ago). Apparently the ESC was known to take a dump. The solution was to eliminate it and physically retard base timing at the distributor.
 
My '86 had an LE9 305ci, and did have the ESC/EST. It also had vacuum advance. From my understanding, the system exists only to retard ignition timing, not "advance" it to a pre-set physical limit.

My ESC module (and AFAIK all of them) is mounted behind the glovebox.

Interesting. Well, that would make sense, I guess. I based my conclusion on the fact the shop manual specifically located it on the brake pedal bracket. Also, it specifically stated that ESC equipped trucks with EST HEI distributors did not use vacuum advance. :shrug:

I kept the "ECM" or ESC (or whatever the hell it is) when I pulled it. I'm going to check its wiring harness color coding to investigate further.

I'm interested to see where this thread goes. I also had TCC. It was unfortunately eliminated during an engine fire. :crazy: I have some alternate method of lockup installed via a Tranny shop.

What ran your TCC before the fire? The shop manual seems silent on what ran lockup on trucks without the ECM. I suppose it was a vacuum switch setup like many of the aftermarket kits.

I can provide the details of my FACTORY APPROVED HEI mod if you're interested (released in a service bulletin years ago). Apparently the ESC was known to take a dump. The solution was to eliminate it and physically retard base timing at the distributor.

Please do! I would really appreciate that. If nothing else, I will compare to what I have now on this 350 and see if everything is jake.
 
What ran your TCC before the fire? The shop manual seems silent on what ran lockup on trucks without the ECM. I suppose it was a vacuum switch setup like many of the aftermarket kits.

I don't know. I know it was electronic. When I would touch the brakes enough to get the tail lights to come on, the TC would unlock. Now it's no longer electronically controlled. The guy at the shop said he installed the same kit used to install a 700R4 with lockup in an older vehicle.

Please do! I would really appreciate that. If nothing else, I will compare to what I have now on this 350 and see if everything is jake.

More info:

http://groups.google.com/group/rec....2b?hl=en&lnk=st&q=esc+service+bulletin+chevy#

Some of my old Usenet threads:

http://groups.google.com/group/alt....db?hl=en&lnk=st&q=esc+service+bulletin+chevy#

http://groups.google.com/group/alt....q=esc+service+bulletin+chevy#33cb912b1a930001

Interesting problem I ran into while performing this, and the solution. Read the initial post, a few afterward, then skip to post #20 where the light bulb comes on over my head. :D Read post #35 for an even better description of the wiring of that particular HEI.

http://groups.google.com/group/alt....q=esc+service+bulletin+chevy#15a8c9f5e25006ce


BTW, the normal mod is basically jumpering two wires together coming out of the HEI.

Via a guy on Usenet from back in the day:

Fastest way was to pull the
glove box down and cut the green and black wires and splice them together. Neat, clean and protected from the elements. Of course, this assumes everything forward is in tact.
I did mine internally, so that no additional wiring was coming out of the HEI. You'll see the "pass through" connector (kind of yellow) in the following picture. Basically, I jumpered the two outside pins together and called it good.

The way the ESC/EST works is this... The signal from the pickup coil is sent out of one of the two wires on the end of the module goes to the ESC. The ESC determines via a knock sensor whether or not spark needs to be retarded. If so, it delays that signal from the pickup coil from completing the circuit--thus retarding timing. The ESC basically intercepts the signal. A standard old-school HEI has 2 pins on that end, not three. Both connect to the pickup coil. The ESC version has 3 pins. One side is connected to the pickup as normal. The other two are an "IN" and an "OUT", with the ESC/EST box residing in-between.

If you jumper the "IN" and "OUT" together, you essentially have a 4-pin module, because you complete the loop/circuit. Simple, huh?

Here's my internal mod... It's the black wire with the red "butt" connector. Notice that I reused the original BROWN connector from the ESC circuit. You could just as easily use a wire with two female "spade" connectors.


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As I stated before, the easiest and cheapest way to bypass the ESC is to just unplug the HEI from the ESC (inside the dash) and jumper the two necessary wires together. I like my way, because it's self-contained in the distributor. The "notch" in the distributor base is for the wiring harness to pass through. That's the only concern I have. Water could more easily get in there. Easy to fix though.

I hope all that explains it to where it's understandable.
 
Awesome tech - even if I don't need it on this swapped engine, someone else will. Thanks! edit - from reading the links, I see that you retained your original distributor from the 305 when you did your 350 swap and that's likely a difference in our setups (let's hope).
 
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Small update

Money and time. Money and time. I have accomplished a few things, though. I modified my fuel cell to now include a return line and a Chevy sending unit -

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There is no way I could write the tech or parts better than Billavista did on Pirate, so check this link:http://www.pirate4x4.com/tech/billavista/Fuel_Cell/

Essentially, I followed his model to a "T", including the Summit Racing part numbers. A nice feature of the sending unit from Summit is that it comes in its own cylinder so you can retain your aviation foam. I went overboard with the 8AN fittings, 6AN would have been plenty.

Second, I redid the cruddy Tuffy Security Console to sport olive drab and a camoflage arm rest -

Before:
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After:
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The backing board underneath the old cushion was rotten, so I stole a bamboo cutting board from my wife to use as new one. (Let's keep that one between us). The camo cover is from an old pair of BDU's and a little Scotch Gard layered on top. The lock was trashed, so I bought a new one from Tuffy, with keys, for $11.

Next, and perhaps most importantly, I finally got the under-dash wiring sorted out (though it may not look like it) and the manual column in:

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Every wire you still see hanging is labeled and I actually know where it all goes. All the old stuff is gone, HVAC, cruise control, ESC, garbage switches, etc. I will not finish buttoning up the interior wiring until I have the dash ready to go back in but the column is fully installed and wired. I won't test my repairs to the harness until I get the floor shifter in (need to wire the neutral safety switch and reverse lights). Just to get this far involved a great deal of poring over the shop manual wiring diagrams, followed by careful teasing out of the factory harness of the undesirable stuff. Quite a few wires needed resoldering. The good news is, I know it inside and out now, so trail repairs should come easy.

Still needed in the wiring department will be under-hood cleanup and under-chassis. The good old 350 doesn't need much in the way of wiring to run, happily.

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Before we move on to the other under-hood wiring pics below, let's pause on this first pic for some more transmission (700R4) tech. The vacuum switch you see here - as best I can tell - was originally part of the torque convertor lockup circuit. I've discussed this a bit in post 60 above.

There is a good discussion of 700R4 lockup identification and how it works elsewhere in the Garage -

http://coloradok5.com/forums/showthread.php?t=85020

My plan is to use an aftermarket solution like I discussed in post 60 and be done with it. If you are hot to diagnose convertor lockup problems in your factory setup, though, here is a good article on how to do it -

http://autorepair.about.com/cs/troub.../aa061701a.htm


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edit - identified by ColAdo82K5 below.


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Old knock sensor that hasn't been hooked up in a long time. I'm thinking ditch it and put in a pipe plug. No use for it I can see with a Holley Truck Avenger and plain vacuum advance HEI.


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Oil pressure switch.


I don't have a pic, but I also had the radiator reconditioned at a local shop.
 
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You might know this one already, but the 8th picture down, the wires shown are the electrical tailgate wires. Single is constant hot, and the other two are the "up" and "down" wires, which recieve power via the switch.
 
Transmission shots

These are just some transmission identification pics I took. I never could find the cast number on the case under the filth (I've pressure washed and knocked at least 100# of dirt off this thing and it just keeps comin').

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...

Little more "progress".

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Everyone knows there's nothing worse than a couple of rusty Hookers . . .

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On the driver side above, you can see the temperature sending unit at 9 o'clock. Taking out the rusty header bolts was a special kind of fun.

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Got the cowl off so I can dig out 25 years of crud.
 
Instrument Cluster Part Needed

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In the shots above, you can see I am missing 1 of the 3 metal clips for the factory battery gauge. These clips are how the gauge gets the signal from the printed circuit board on the back of the cluster.

Anyone have 1 or 2 they could send me?
 
Inching forward

Front axle update - got the drilling pretty much done and one of the holes tapped. 4140 5/8" threaded rod stock will be used to make the new studs:

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Wiring update - have no pics to show it but fixed the rat's nest that used to be the tail lamp harness. Right about the time I started feeling good about the wiring, I saw this (think bare wire going to the starter laying across the motor mount might be a problem??):

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Missing part of the day - isn't there supposed to be some sort of plug here (starter)?

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Parts update - teaser pics:

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1. Fel-Pro Exhaust Header Gasket set #FPP-1444 $17.95
2. Hedman Elite Hedders #HED-69830 (ceramic coated) $161.95
3. Stage-8 locking header bolts #STG-8911 $41.95
4. Summit Racing remote solenoid #SUM-G1750 $21.95
5. Taylor spark plug boot protectors #TAY-2528 $60.39
6. NAPA 700R4 filter & Gasket set #1-9718
7. Painless Wiring 700R4 torque convertor lockup kit #PRF-60109 $161.95

Everything but #6 came from Summit Racing.
 
Man that looks really great i cant wait to see it done. Im curious as to why you chose the 42 iroks? Suscribed.

Honestly, no real science there - I had a chance to get a good deal on them and I know this combo was run with good results with these axles (5.86 gearing) on the last rig they were under (rear 60 is likely going to need alloys/chromos though in the future, to live long-term). IROKs get decent ratings from other wheelers for all-around performance and these were in good, used condition and already mounted on beadlocked rims that fit my lug pattern.

The rough to-do list from here is still depressingly long:

1. Finish front axle perch and hang axle (sweating whether tie rod will clear leafs at droop - the prior owner used coils so no clue if this will clear)
2. Hydraulics (steering)
3. Brakes (master cylinder, proportioning valve, lines, etc.)
4. Finish-weld all suspension/final clean & rattle-can axles
5. Shocks (need to have axles hung & measure first)
6. Body patches/rust repair/Herculine tub/rattle-can paint
7. Mechanical/body cutting & re-assembly/tuning/maintenance (lots of things included here to numerous to list)
8. Cage/install seats/sliders (buy tube, bend, etc.)
9. Bumpers, front & rear with recovery points
10. Driveshafts (unclear now if these will be bought or fabbed)
11. Winch (got a line on this)
12. Winch battery (I have my eye on an Exide for this, but $$$)
13. Dual battery wiring
14. Floor shifter install
15. SYE (?) (not a huge fan of my 208, but all solutions add $/complexity)
16. Bumpstops (thinking Timbrens)
17. Exhaust/mufflers (figure no cats, true duals, flowmasters)
18. Gauges (oil pressure, volts, tach, trans temp, water temp)
19. Windshield (this one is like looking through a milk jug and the seal leaks)
20. DIY "bikini" soft-top (will raid marine section at Academy)
21. Rock lights/off-road lights & associated wiring/relays (Tractor supply/Wal-mart)
22. Rear axle seals and yoke replacement
23. Motor/trans/t-case mounts (?) (need to check their condition)

After that, we get into more optional stuff like 35-spline outers, chromo/alloy shafts, e-brake solution, etc.
 
Closer or further?

Got the intake manifold partly cleaned up, old valve covers off, exhaust ports cleared of carbon and tarted up a few brackets -

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And, a few steps closer on the Dodge 60, though not finished yet -

Then:

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Now:

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Then:

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Now:

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Piece Work

Getting the dash together. Most folks will gut the factory instrument cluster and use those ports for aftermarket gauges. Or, they will make a custom dash from sheet aluminum or light-gauge steel. In my case, I wanted to preserve the factory instrumentation, mainly to save time and money. In retrospect, not sure if I saved either. My AC vents will be gone, as will the HVAC controls and the factory radio. So, what to do with all that real estate -

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Templates from construction paper. Underlying material is 20 ga. steel that cost about $10 at Tractor Supply Company.

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After some quality time with a sabre saw, grinding wheel and wire wheel.

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Mounting holes drilled. The plate mounts for the AC vent at top right and the HVAC slot were a huge pain.

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As you can see, the solution was trim screws and speed nuts (flat and "L" - all from ACE Hardware). The L-bracket speed nuts had to be trimmed and then bent to custom angles less than 90 degrees and re-drilled to work properly in those slots.

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Repeating my ritual of forking over cash to Summit Racing, I bought:

Front Row, Left to Right:

VDO-310106 Gauge, Vision, Oil Temperature, 150-300 Degrees F, 2 1/16 in., Analog, Electrical, Black Face, $25.95 (I will use this as a transmission temperature gauge - Summit did not have a P/N for a VDO Vision series electrical trans temp gauge.)

VDO-350104 Gauge, Vision, Oil Pressure, 0-80 psi, 2 1/16 in., Analog, Electrical, Black Face, $25.95

VDO-310105 Gauge, Vision, Water Temperature, 100-250 Degrees F, 2 1/16 in., Analog, Electrical, Black Face, $25.95

VDO-332103 Gauge, Vision, Voltmeter, 12 V, 2 1/16 in., Analog, Electrical, Black Face, $22.69

Back Row:


SUN-CP7908 Tachometer, Super Tach II, 0-8,000 rpm, 2 5/8 in., Analog, Electrical, $41.99

I was having trouble finding relatively inexpensive electrical gauges locally. AutoZone let me down, the Sunpros they had were mechanical only. Note that the VDO part numbers above do not include the sending units, so you will have to get those separately:

VDO-323900 Sending Unit, Temperature, 0-250 Degree, Kit $23.95

VDO-323905 Sending Unit, Temperature, 0-300 Degree, Kit $20.69

VDO-360900 Sending Unit, Oil Pressure, 0-80 psi, Kit $35.95

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My method here was to use the hole saw (2 1/16") as the template to draw up the gauge placements and then tap the pilot bit as a center punch so I could start the cut properly centered. Beneath is a scrap 1x4 piece of wood so I could clamp the metal piece - otherwise it would bend under the pressure of the drill and the hole saw would walk.

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The two gauges going in the HVAC slot mocked up. You can't get any tighter than that and have them still fit. I had to cut down the "L" bracket speed nuts a bit and enlarge the HVAC slot.

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And the rest done in similar fashion. The very top right plate will eventually have switches in it. The plates will also be rattle-canned OD green after I am through fooling with mockup.

Although the tach is not in an ideal viewing position, it will do. I am proud of realizing I could just use a hose-clamp on the back side of it to hold it in the panel mount (it came with bracketry for a column mount).
 

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