- Thread starter
- #141
this is correct. the vortec needs a keyed 12v source, another that is hot in the crank position, and a ground. It will run with just those connections. the rest is stuff like tach signal, check engine light, ect....
Builds 1994 FZJ80 5.3l and 4L60e swap
- Thread starter rockrod
- Start date
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this is correct. the vortec needs a keyed 12v source, another that is hot in the crank position, and a ground. It will run with just those connections. the rest is stuff like tach signal, check engine light, ect....
- Thread starter
- #142
yes - i just plugged it right into the truck fuel rail since it's a single line style.
alia176
SILVER Star
That is very cool, thanks for the answer. Once you give the trans a speed signal, it sounds like you can at least drive it around while you figure out the wiring integration.
- Thread starter
- #144
the trans gets in own signal from the gm harness so those wires are mentioned are essentially the ones needed to make the engine run run and the transmission shift.
- Thread starter
- #145
Things are moving.
got the trans cooler lines run, built a new starter lead cable from some 2 gauge welding cable and did a test spin of the motor with the starter.
What's left?
Wiring - I have to do all of the integration, mount the PCM, reinstall the t-case wiring harness, and general cleanup. I also have to do install the vapor canister and wire it up.
And exhaust.... I was planning on reusing the stock muffler and tail pipe section. I just can't decide if it's going to create too much of a restriction, or should I scrap that plan and get a new muffler.
I don't want it loud so not sure of the best choice for muffler.. maybe a borla or dynomax?
got the trans cooler lines run, built a new starter lead cable from some 2 gauge welding cable and did a test spin of the motor with the starter.
What's left?
Wiring - I have to do all of the integration, mount the PCM, reinstall the t-case wiring harness, and general cleanup. I also have to do install the vapor canister and wire it up.
And exhaust.... I was planning on reusing the stock muffler and tail pipe section. I just can't decide if it's going to create too much of a restriction, or should I scrap that plan and get a new muffler.
I don't want it loud so not sure of the best choice for muffler.. maybe a borla or dynomax?
Great to see you are getting close.
Only because it is there I would rehook up the factory exhaust to give you a noise baseline.
Borla or Dynomax will not be quiet. Consider a muffler with offset in and out to keep noise to a minimum, I went with a Walker. Aftermarket cats will offer less restriction then factory also.
- Thread starter
- #147
good thought. I need it quiet and a lot of the welded mufflers (flowmaster, ect) create too much interior resonance. Stock for now...
- Thread starter
- #148
Found some time today and started the exhaust fabrication. I decided to do a crossover style into one cat. There is no room for a cat on the driver's side without killing the trans sensor and shifter cable.
self made pipe merge.
not the best welds - it's hard to weld exhaust tubing with a mig welder.
self made pipe merge.
not the best welds - it's hard to weld exhaust tubing with a mig welder.
Looking forward to seeing how you do this. I need to redo mine... Lots of pics please. 
- Thread starter
- #150
well - good news.
It runs. I wired up the ecu temporarily and it started right up.
It runs. I wired up the ecu temporarily and it started right up.
SWEET! congrats! i bet it feels good.
- Thread starter
- #152
Went for the first test drive today - ran to the gas station and back.
the bad - will not shift out of first gear when the selector is in drive. I can manually shift into second and it will go into second, but there's no direct or OD.
I hooked up my handy OBD scanner and noticed there is an intermittent signal coming from the speed sensor. It will occasionally jump from 0 mph to 20 or 30 mph but it's definitely not a consistent signal. I suspect this is causing the trans to go into limp mode.
I recall when installing the speed sensor into the Marks adapter that it was not the best fit - I wonder if it's spaced too far out or not square in it's bore.
It runs very well though and there is definitely a significant power increase. The 5.3l is no slouch.
The cooling system works great - at no time did the motor ever go over 198f.
More to come once i figure out the speed sensor issue.
the bad - will not shift out of first gear when the selector is in drive. I can manually shift into second and it will go into second, but there's no direct or OD.
I hooked up my handy OBD scanner and noticed there is an intermittent signal coming from the speed sensor. It will occasionally jump from 0 mph to 20 or 30 mph but it's definitely not a consistent signal. I suspect this is causing the trans to go into limp mode.
I recall when installing the speed sensor into the Marks adapter that it was not the best fit - I wonder if it's spaced too far out or not square in it's bore.
It runs very well though and there is definitely a significant power increase. The 5.3l is no slouch.
The cooling system works great - at no time did the motor ever go over 198f.
More to come once i figure out the speed sensor issue.
- Thread starter
- #153
Sweet! problem solved. It was the VSS. When I installed the sensor, somehow it was mounted cock-eyed in the hole and causing the signal to be interrupted. I removed it, popped it back in and made sure it was flush in the hole and viola, all gears are now present.
I have to say - anyone who poo-poos a vortec swap is really missing out. Even with a 'small' 5.3l, it moved right on out. before it was a struggle to get to 70 mph, now it's effortless. Even better, once it's in OD, it stays there unless it's a really steep grade.
I can only imagine what an LQ4 or LQ9, or even an LS2 must run like.
There's more still to do, but the good news is that it runs and drives.
I have to say - anyone who poo-poos a vortec swap is really missing out. Even with a 'small' 5.3l, it moved right on out. before it was a struggle to get to 70 mph, now it's effortless. Even better, once it's in OD, it stays there unless it's a really steep grade.
I can only imagine what an LQ4 or LQ9, or even an LS2 must run like.
There's more still to do, but the good news is that it runs and drives.
Congratulation on the good news
Video
Video
rockrod said:
Word up my vortec brother!!!!
RockJock82
Sometimes you have to kick a little A$$
- Thread starter
- #157
getting there! I am going to drive it to work tomorrow so I will try to get some video posted up on youtube. I just reinstalled the front bumper tonight so it's ready to go tomorrow.
My gauges are not working yet (well, the fuel and volts works). No oil, coolant temp, tach and for some odd reason speedo. The speedo should be working regardless - I think I goofed something up on that harness.
I need a 14mm 1.5 tap to open up the hole in the head (it's currently 12mm 1.5). No one makes an adapter and I don't have a lathe to turn my sensor down.
I also need to figure out the thread size for the stock oil pressure sender and then tap the oil cooler block off plate on the f-body pan.
I thought the tach would work after having the PCM reprogrammed to send a 6 cylinder signal but no dice. I picked up a 0-10k ohm potentiometer and will build a pull up circuit to amplify the tach signal coming from the PCM.
Other than that, it's just a matter of cleaning up the wiring and making everything permanent.
It's like driving an entirely different vehicle. You don't realize just how underpowered 80s are in stock form until you drive one with a v8.
My gauges are not working yet (well, the fuel and volts works). No oil, coolant temp, tach and for some odd reason speedo. The speedo should be working regardless - I think I goofed something up on that harness.
I need a 14mm 1.5 tap to open up the hole in the head (it's currently 12mm 1.5). No one makes an adapter and I don't have a lathe to turn my sensor down.
I also need to figure out the thread size for the stock oil pressure sender and then tap the oil cooler block off plate on the f-body pan.
I thought the tach would work after having the PCM reprogrammed to send a 6 cylinder signal but no dice. I picked up a 0-10k ohm potentiometer and will build a pull up circuit to amplify the tach signal coming from the PCM.
Other than that, it's just a matter of cleaning up the wiring and making everything permanent.
It's like driving an entirely different vehicle. You don't realize just how underpowered 80s are in stock form until you drive one with a v8.
- Thread starter
- #158
Sorry - no video yet 
Still working bugs out.
So far I have been able to get the oil pressure, speedo, volts and fuel level gauges working. Water temp is still in the works. I found that the toyota sender is actually a 16mm x 1.5, not a 14mm. I am making an adapter bung that will screw into the LS head and then allow an unmodified toyota sensor to screw into this.
For some reason, my CDL is not working. I think I may have inadvertently deleted a ground wire so I need to pull that harness out and do some digging.
I have a scan gauge plugged in to the OBD port so that I can monitor the vitals. The motor has been running about 190f and the fans have no problem keeping the motor at that temp in traffic. I installed an indicator light from DCC that changes color from green to red as the fans go from no speed to full speed. The light is usually green while cruising (no fan rpm) to barely orange in traffic.
The MPG indicator on the SG shows a real time 18ish mpg on average at a 65 mph cruise.
I have been driving it around now and man, it runs really well. I can't get over how easy it is to accelerate into traffic. No longer do you have stay in the slow lane.
LOVING IT!
Still working bugs out.
So far I have been able to get the oil pressure, speedo, volts and fuel level gauges working. Water temp is still in the works. I found that the toyota sender is actually a 16mm x 1.5, not a 14mm. I am making an adapter bung that will screw into the LS head and then allow an unmodified toyota sensor to screw into this.
For some reason, my CDL is not working. I think I may have inadvertently deleted a ground wire so I need to pull that harness out and do some digging.
I have a scan gauge plugged in to the OBD port so that I can monitor the vitals. The motor has been running about 190f and the fans have no problem keeping the motor at that temp in traffic. I installed an indicator light from DCC that changes color from green to red as the fans go from no speed to full speed. The light is usually green while cruising (no fan rpm) to barely orange in traffic.
The MPG indicator on the SG shows a real time 18ish mpg on average at a 65 mph cruise.
I have been driving it around now and man, it runs really well. I can't get over how easy it is to accelerate into traffic. No longer do you have stay in the slow lane.
LOVING IT!
- Thread starter
- #159
The tach function is kicking my arse. The pull up circuit didn't work and then I read on another toyota forum that the toy tach doesn't work with square sine wave that the vortec PCM puts out.
I called Dakota Digital and they say their magic box will do the trick. It should be here next week.
I called Dakota Digital and they say their magic box will do the trick. It should be here next week.
alia176
SILVER Star
nickel and diming you to death?
