CK5
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79' GMC C15 - Spruce Caboose

79 GMC 1500
The factory TBI trucks have a glove box that is different. The black plastic box is recessed in on one side to clear the ecu. Maybe you could swap out the pocket and keep the metal from yours.
 
@mrk5

I woulda have never remembered that about the glovebox in the tbi k5. Thats a good idea. Ill look into sourcing one of those guys.
 
That picture came from a company I use called Ecklers. I didn't see what the price was tho. Sad thing is I would've had one from my crew cab, but I junked all the factory dash stuff.
 
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something like this would work for sure. The glovesbox in this truck is actually worthless also as the entire black plastic part that fastens to the underneath of the glovebox is all cracked. If you open the glove box it yardsales your crap across the floor as the box itself also falls out.. Here you are requires to have two VIN locations, and one of my two is in the glovebox on a sticker so i should probably hang onto that.
 
Finding damaged items when your close to a start up is not fun:doah:PXL_20210405_211952588.jpg
 
Turns out summit will put you on hold for so long you cant help but try and fix the problem yourself beyond all better judgement.. This time it paid off luckily. Managed to take the ring of strange electrical probe pin thingys, and gently massage this back into its correct location. The plug then went on the trans with no issues. Wont know til start up if its an issue, but if it is ill tackle the return process then.

Now that that was sorted, time to keep pluggin away a little day by day and cross things off the list for the PCM. Each harness that plugs into the terminator ports, has its own switched 12v power source for the relays, solenoids or whichever dedicated power it needs. There are a total of 5 grounds for the PCM and harnesses.

So far this is where im at....

PCM main power harness:
-12v directly to the battery (dedicated post)
-Ground directly to the battery (dedicated post)
-12v `to switched power source ( 12v while cranking ) / connected to the tan wire in the bulkhead for the distributor.

Trans control harness:
-12 volt switched power into ACCSY port on fuse block ( dedicated )
- Chassis ground ( yet to be determined )
- Speed turbine plug ( 4l80 only ) unused
- VSS speed sensor
- Trans control main plug.

DBW harness:
-12v switched power into ACCSY port on fuse block (dedicated )
- 12v brake switch for torque converter to unlock. ( wired into the white wire in the brake switch )
- Chassi ground.b ( YTD )
- Holley states the PCM has only been used and calibrated for a specific gm pedal. I did get the pedal from the donor, but ive ordered up the PN provided by holley incase the OE pedal doesnt work. Its one of those wierd all plastic pedals with barely and pedal movement..
- Throttle position sensor/motor on order as i broke the tabs off the one that came with the motor, so the clip doesnt work to secure it.

Engine harness:

-12v switched wired into the fuse block.
- Two grounds located on the back of each cylinder
- IAC unused
- TPS unsued
- Coil harnesses on order.
- Manifold air temp drilled and installed in intake tube.
- Crank sensor and knock sensors in.
- O2 sensor / Installed.. but as usual i didnt check the clearances on anything, and having blind faith that things will work out only gets you so far. Put the collector in the vise, eyeballed a ten percent angle and drilled it, welded it... even painted it before checking. Either theres a monkey on my back or this is a little too close for comfort. Between the crappy headers and me not checking this is the result.


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For now im going to call that a win. The linkage all moves freely with no contact, but its a bit of a clusterfug goin on. The only wires i have left to figure out are the chassis ground which i need to drill and secure somewhere accessible with the inner fenders on.


Turns out i had an inner fender i got from someone awhile back in the sea can and its for the side i need. Very solid, but needed a wire wheeling for sure. I installed it and im not sure what year or make its from, but its bent and also a tight fit. The white paint pen line is the area ill trim off around the top control arm area. Got that painted up and drying now.

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Once thats installed i can mount and make the airbox bracket. The trans cross member will make the exhaust so much easier to route. Its going to be quite the frankenstein exhaust job using whatever i can find. luckily im not doing duals. Plan is single 3 inch exhaust, y pipe and drivers side dump at the back of the box. Hoping to get the cab on the quieter side after a k5 with no carpets, flow master 40 under the seat at 2600 rpm on the highway. Been finding some borla exhausts that are a nice, quiet but mean rumble...but for now this random 3 inch mufflers going in regardless of noise.


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sending unit done , Fuel pump is good to go, need to get a single 10 awg waterproof connector, to put inline with the relay. Ill run the sensor wire seperately when i end up with some dash.
 
I like that O2 sensor bung with the flange on it.
 
@mrk5

Looking at the ones i ordered and the one that came with the kit, i think these ones are way more up my alley of welding skill and ease of placement. Only thing that would have been nice about the standard O2 bung they provided, is it wouldnt be so proud of the pipe and itd have more clearance towards the shift linkage but oh well.
 
Yeah, I was thinking it looked easier to weld. Funny what you mention about it sticking out so far. I've found several instances of people extending the O2 bung an inch or so out further to get longer life out of the O2 sensor.
 
oh cool, never heard of that but makes sense? Thats probably what the manufacturer was intending
 
Im still waiting on the coil harnesses to show up, but in that time ive just been puttering and getting the little things done. The new gm pedal came in the mail. Im actually quite happy holley "required" this pedal. The one i had from the donor truck had an inconvienent curve to it.. Which put it far to the right from where it bracketed to the firewall. The new pedal is way more linear to the mounting point. Its nothing fancy, but it was free to make with scrap laying around so i think thats a win. I traced and cut a rough template out of some flat steel, drill the holes. I just welded it to the stock bracket which i cut.PXL_20210410_201054583.jpgPXL_20210410_201124116.jpgPXL_20210410_201154366.MP.jpg


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The new pedal has 3 mounting points, two are further back from the backing plate that the other. So two of my bolts going through have a 3/4 inch gap. The only leverage on the pedal is on the back of the plate, so the nut is tight the whole time but i do plan on cutting some solid spacers out of some thick walled brass tubing i have laying around somewhere..

Thanks to @mrk5 i got the right filler tube and the fuel tank is finished for now.
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Yesterday the coil harness showed up, and today i got around to trying to fire it up. After trying to find a location for the stock air box, i eventually just said screw, it and got a 2007 gmc air intake kit. With the location of the overflow container being right beside the rad on the core support, i couldnt get the box in without noving it back, which raised it up and i was worried about the hood closing, along with spending alot of time to make it fit. I took the MAT sensor and put it in the intake tube also. I also intalled the new TPS, its quite the fancy flapper mover...
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I had two seperate fuel leaks that required cutting and changing of fittings, i accidentally wired the 12v power source for the fuel pump and injectors, to a non 12 volt source.. after fixing that and still not having power to the holley 12v green fuel pump trigger wire, i discovered i wired the relay and switched the ground and 12v signal poles.. after fixing that and still not having power i put my multi tester in the holley relay and found out i had a bad ground for the holley relay. The terminator x max has a fuel pump relay built into the harness with a 14 AWG green wire that is good to run a fuel pump directly under 15 amps. Over 15 amps it requires another relay and a 10AWG to the pump.. Youd think the green wire would be 10awg and capable of powering any fuel pump directly?
After that i had no fuel and realized i had mixed up the feed and return line on the filter... cracked them both open to check and got gas diectly in my eyes.. after sacraficing a few nuns and getting them switched, i had fuel at the rail. Got the air out of the system and it fired right up.

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AFR is way out to lunch as the O2 sensor is about 3 inches from an open air source but its alive and has oil pressure so im good with that. Next will be to get this exhaust set up so i can then proceed to tune the PCM.

Disk brake brackets will be here shortly. Turns out the cpp brake calipers i purchased have a 7/16 -20 banjo bolts and dont work with the brake lines i have for the front so i bought some reman ac delco front calipers and i may use the CPP calipers on the rear if i decide to buy the cpp brake lines that go with it.. Most likely im going to rebuild the front OE caliper that needs a new seal and then put them on the back. The new calipers will be added to the tuition pile.


Also i was wondering when i set up the terminator x, it had 3 options for cam shaft duration.
Under 230 degrees
230-260
260 degrees - over

I chose under 230 as the largest duration is 227 at 050 lift in exhaust? theres no way they mean the advertised duration is there?

The cam i put in there has these durations listed.
Intake Duration at 050 inch Lift:
218
Exhaust Duration at 050 inch Lift:
227
Duration at 050 inch Lift:
218 int./227 exh.
Advertised Intake Duration:
278
Advertised Exhaust Duration:
287
Advertised Duration:
278 int./287 exh.
 
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As for the alternator im only getting 13.3v. The 2006 and up 2 pin regulators do not work without feedback from a PCM. The earlier Ad244 regulators ( 4 pin ) can be made to work either way. I am planing on running a single wire DR44G Ad244 alternator with a 470 ohm 1/2 watt resister inline to excite the charging. I was going to swap out the pins but when its all said and done its too much to toss into a potentially junk alternator.

Turns out when righty tighty turns to righty loosey the fun slows down.. I stripped the trans cooler female threads on the radiator side. I ordered a stand alone cooler that im hoping wont mean redoing both lines from the trans and just bypass the stock one.

Made some progress on the exhaust today. Went and picked up a 4ft piece of 3 inch and a 3 inch u bend. I placed the muffler where i have the factory hanger just behind the cab, then built the exhaust from the collectors back as i have a recycled chunk of rear exhaust, im hoping will work. Got most of it plumbed up.. I will need to get my drive shaft extended a couple inches so it sits deeper on the spline. Its only about an inch or so on there, and itll probably slip out a bit further depending on the final angle with the tires on the ground but it helped me visualize where to route the exhaust. Im hoping the trans will be able to dropped without touching the exhaust system as the crossover sits just passed the slip yoke u-joint.. Got the exhaust on to the end of the muffler for now.

Fired it up again today and seems to have started making a noise from the front end accessory area.. sounds like what im hoping is a shit alternator, power steering pump ( since it did puke out all the fluid from the rear fitting ) or water pump. Its not a ticking noise or anything, but its one of those alarming mystery sounds for now...

It was nice to get the welder out and practice some more. The bench welding was fun, under the truck was fun too with all the crazy angles and all but tricky for sure.


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It did... Theres also a good 1/16 inch+ of play in and out on the shaft...and then the noise when it rotates.
 
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