Are you keeping the stock gauges? I kept mine and everything works like stock.
1995 fzj80 5.3/4l60e/np203/splitcase swap
- Thread starter Mr.Bryan
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- #22
warpdriv said:
Is it really just one wire that sees 12v at on and crank? How does the system determine the difference?
And too late on the engine thing. I may be able to get to the sender though. Did you guys reuse the Toyota senders?
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- #24
By the way, I didn't see that any of you guys mentioned changing out the brake switch. Is the 80's a 2 position and you guys just tapped into the wire? I have the switch from psi, but if I don't have to install it, I won't.
the brake switch is easy. there's a wire in the IH1 connector that sends 12v to the 1FZ computer. By using this wire and a 2 position relay, you feed the power through the normally closed side so that the relay cuts 12v going to the computer when the pedal is push.
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- #26
I got ya. I'm still having a hard time understanding this IH1 connector stuff. As far as the brake switch though, all I would need to do is splice in the load wire to one of the wires behind that connector?
Do I need to use the other side of that connector that I pulled out with the wiring when I took the engine out or can I just leave that whole thing disconnected and just splice into the back side of the connector behind the glove box?
Do I need to use the other side of that connector that I pulled out with the wiring when I took the engine out or can I just leave that whole thing disconnected and just splice into the back side of the connector behind the glove box?
i would splice into the engine harness side of the connector and leave the body harness side alone. it's a lot easier to unplug the connector from the body harness and work with it on the bench and then just plug it back in.
wow that is one badass build, i do have parts left over from my LS1 car, you can use the LS1 intake manifold and get more power, i also have the factory cam that will increase power over that 5.3 truck cam.
Originally Posted by rockrod
Are you keeping the stock gauges? I kept mine and everything works like stock.
I wasn't planning on it but if its just a matter of splicing a few wires, then I might change my mind...
You'll need to figure out how to run the speedo off that setup since you are running a split case.
Are you keeping the stock gauges? I kept mine and everything works like stock.
I wasn't planning on it but if its just a matter of splicing a few wires, then I might change my mind...
You'll need to figure out how to run the speedo off that setup since you are running a split case.
- Thread starter
- #30
Ok. That's what I thought. I was going to try and not mess up that connector for resale purposes, but if it makes my life easier...
As far as the speedo goes, that's one of the main reasons I was thinking of tossing in some autometers. I'm not sure how it would work off that and quite frankly the appearance of the gauges doesn't bother me.
At this point, I'm just going to use a gps until I get it sorted.
Rockrod, for the brake switch, do I have to pick up a relay to wire inline between the 12v from the 1fz harness to the gm computer?
i am working on modify the spread sheet so that the wire colors you have match up to the plugs - it takes a little time but I should be able to get you pointed in the correct directions. The stock speedo will work just fine, and so will the tach, fuel level, water temp, ect. I mounted a scan gauge so that I can compare the pcm values to the stock gauges and they are pretty close. the nice thing about the scan gauge is that it will show a number value for the water temp - it pulls it right from the vortec pcm.
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- #32
Sweet!
I just took care of the fuel pump relay. I'm just grounding out one of the wires so that the fuel pump will see 12v always when the ignition is on and it bypasses the resistor.
As far as the brake switch, I understand the idea of it, just not sure the best way to set it up. Is there a relay you know of that I can use to cut the 12v when the brakes come on? If I understand it correctly, I need the vortec ecm to see 12v all the time, then have a relay cut the 12v when the brakes are pushed. Seems straight forward, just not sure of the best way to accomplish this. Radioshack?
Will I need to bother with the IH2 connector at all? If not, I can just leave it unplugged and hanging right?
I just took care of the fuel pump relay. I'm just grounding out one of the wires so that the fuel pump will see 12v always when the ignition is on and it bypasses the resistor.
As far as the brake switch, I understand the idea of it, just not sure the best way to set it up. Is there a relay you know of that I can use to cut the 12v when the brakes come on? If I understand it correctly, I need the vortec ecm to see 12v all the time, then have a relay cut the 12v when the brakes are pushed. Seems straight forward, just not sure of the best way to accomplish this. Radioshack?
Will I need to bother with the IH2 connector at all? If not, I can just leave it unplugged and hanging right?
I ordered a pack of 5 terminal 12v relays from amazon - they came with the pig tails and everything. just wire the relay so that you have 12v feeding power to the normally closed side, and then when the brake pedal is pushed and sends power to activate the relay, this in turn cuts the 12v going through it to the PCM and then the PCM will unlock the converter.
it would increase the power but it would also move the powerband up. these cruisers are heavy so the vette stuff probably wouldn't be that great in a 5.3l engine. this is why i specifically chose the L33 for my swap - it's still a 5.3 but it's all aluminum, has a cam with more lift over an iron block 5.3, and 10:1 compression. the heads are also 799 series LS1 heads so it's more of a mid-step from 5.3 to LS1.
here's a shot of the IH1, IH2, and IH3 connectors, and the ECU connectors from the harness on my '94. the other end of this harness would connect to the various sensors and such on the engine and also to the EC1 and EC2 connectors that are located down by the starter on the driver's side and connect the trans/t-case to the ECU and body harness.
On your '95, you don't have the IH3 because this connector on the '94 carries the transmission control circuitry to the TCU. The '94s had a separate TCU and the '95s and later the ECU controlled the transmission - hence the missing IH3 connector on your truck.
This shot is after I had cleaned off the tape and split loom.
this next shot is of the IH1 and IH2 connectors and the rest of the heavily trimmed engine harness - notice the IH3 is gone along with all of the wires that went to the ECU connectors. there is still the EC1 for the connection to the transfer case and speedometer.
here's what is left after culling the unneeded wires:
it's a significant reduction.
On your '95, you don't have the IH3 because this connector on the '94 carries the transmission control circuitry to the TCU. The '94s had a separate TCU and the '95s and later the ECU controlled the transmission - hence the missing IH3 connector on your truck.
This shot is after I had cleaned off the tape and split loom.
this next shot is of the IH1 and IH2 connectors and the rest of the heavily trimmed engine harness - notice the IH3 is gone along with all of the wires that went to the ECU connectors. there is still the EC1 for the connection to the transfer case and speedometer.
here's what is left after culling the unneeded wires:
it's a significant reduction.
Heater hose connections. One is the in and the other is the out.
