4th Gen Camaro Haltech Rebel LS Install
Awesome thread, a lot of good info in here that I'll be able to put to use myself. Especially the info on the fuel pumps. I was going to upgrade my twin 340s to twin 525s, but with what Nic mentioned, I'll be doing a 450/525 combo instead. As for wiring, I found an entire wiring schematic for my Formula online and it helped immensely when doing all the wiring on my car. I am certain you can find the same for yours. Don't sweat the wiring, I didn't have a whole lot of experience when I started and now I feel confident in doing just about anything. One suggestion: Use deutsch connectors everywhere you can. There is no simpler connector to assemble and crimp. They're just about idiot proof. I have used them on all of my add on sensors and wiring.
Do you mind sharing where you found the wiring schematic?
Did you end up keeping the BCM and lights and power windows worked normally?
I'll look into the Deutsch Connectors too, I have some basic weather pack connectors and fortunately I won't need to add much since the Haltech harness has most if it covered.
Joined: Apr 2006
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From: Grand Rapids, Michigan
It may have been on this forum that someone shared a link. It was a couple of years back that I downloaded it and printed it off. I still have it, I'll check in my garage to see what the URL is on it. I piggybacked my car so I could keep my gauges and transmission functions ( reverse lockout, VSS, back up lights ). Everything electrical in my car works like it should, other than I have no turn signals. A project for the winter, as they worked when I first got the car running. I don't think you need the PCM to run anything in the interior, however.
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From: Ohio
Be mindful of the shielded wires. Wired in a spi to mine for flex fuel and driveshaft sensors and both had a tiny strand of shielding making intermittent contact with a pin on my DT connector
Excited to see this!
Excited to see this!
Thinking while I'm in there that I'm going to make a dedicated ground up in the driver kick panel instead of the stud that bolts the dash in, I'm also going to hard wire in the relay for the additional power source under the center console, right now its plugged into the fuse box and I hate how it looks.
The only thing remaining is the Cortex which is next, then getting the dash out and from there I should be able to separate out the engine harness.
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From: Louisiana
Getting closer to getting the dash out, I got all the remaining wiring for all the additional gauges removed and some extra that was in there from God knows what lol.
Thinking while I'm in there that I'm going to make a dedicated ground up in the driver kick panel instead of the stud that bolts the dash in, I'm also going to hard wire in the relay for the additional power source under the center console, right now its plugged into the fuse box and I hate how it looks.
The only thing remaining is the Cortex which is next, then getting the dash out and from there I should be able to separate out the engine harness.
Thinking while I'm in there that I'm going to make a dedicated ground up in the driver kick panel instead of the stud that bolts the dash in, I'm also going to hard wire in the relay for the additional power source under the center console, right now its plugged into the fuse box and I hate how it looks.
The only thing remaining is the Cortex which is next, then getting the dash out and from there I should be able to separate out the engine harness.
Hmmm.....
Question for the group regarding boost control.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
Question for the group regarding boost control.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
On my setup I use dual mac valves and after getting a grip on the Holley controller tuning the boost curve was fairly easy and I've got zero spikes
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From: Louisiana
Question for the group regarding boost control.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
The current 3-Port Mac valve I've been using with the Cortex EBC is going with the Cortex when it sells so my question is should I stick with the single 3-Port valve setup or look at something different?
4-Port Mac valve, dual 3-Port valves?
I will still be using the air compressor to control boost; the previous setup had compressed air going to one side of the mac valve with boost coming in the other side and the lower port going to the wastegates.
Boost control was never an issue, so my thought is to stick with a single three port, but I thought I'd ask the question either way.
My intention is to run around 20 lbs. of boost most of the time with a max of 25 lbs.
how did you control boost that way? Did you have to physically adjust the compressor? Mine is dual 3 port with Vair tank coming in one side, middle t goes to wastegate, and other side vents. Dome pressure sensor on wastegate too, turbo also running to wastegate. Wastegate is 3 port, the two top are dome and mac and bottom is turbo.
He said you want the input from the compressor (dome) to be around the boost you intend on running, that way when you make changes in the profile, its small increments in boost and not big ones.
So right now, I have the compressor regulator set at 20 psi and was running 21.5 psi, so the changes were easy to anticipate and small, iirc it was 1-2 psi per 5% of duty cycle added.
It worked quite well and looks similar to a two-mac valve setup, just less plumbing with the one mac valve basically doing all the venting missing.
What is the benefit/reason for running a dome pressure sensor?
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Joined: Oct 2022
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From: Louisiana
Chris from Cortex (Sirhc Labs) helped me set it up, he's great and his support is excellent btw.
He said you want the input from the compressor (dome) to be around the boost you intend on running, that way when you make changes in the profile, its small increments in boost and not big ones.
So right now, I have the compressor regulator set at 20 psi and was running 21.5 psi, so the changes were easy to anticipate and small, iirc it was 1-2 psi per 5% of duty cycle added.
It worked quite well and looks similar to a two-mac valve setup, just less plumbing with the one mac valve basically doing all the venting missing.
What is the benefit/reason for running a dome pressure sensor?
He said you want the input from the compressor (dome) to be around the boost you intend on running, that way when you make changes in the profile, its small increments in boost and not big ones.
So right now, I have the compressor regulator set at 20 psi and was running 21.5 psi, so the changes were easy to anticipate and small, iirc it was 1-2 psi per 5% of duty cycle added.
It worked quite well and looks similar to a two-mac valve setup, just less plumbing with the one mac valve basically doing all the venting missing.
What is the benefit/reason for running a dome pressure sensor?
the dome pressure sensor is ran to an input so I can go into holley and set my my psi for boost. Mine is set exactly 1v1 so if I put 20 psi of dome pressure I will get 20 psi of boost. Its nice like that because i have alot of control over it. I have my transbrake set at 8 psi of dome so I know im leaving on exactly 8 pounds of boost and I have it ramping up to 20 psi in the dome pressure table so I know im not blowing the tires off when 20 psi kicks in. We just played around with the regulator on the vair tank until it matched exactly 1v1.
Joined: Apr 2006
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From: Grand Rapids, Michigan
Running with a compressor must be different than CO2? I was told you wanted to have significantly more pressure than target boost. I was running 50PSI at the regulator but targeting around 20PSI dome.
the dome pressure sensor is ran to an input so I can go into holley and set my my psi for boost. Mine is set exactly 1v1 so if I put 20 psi of dome pressure I will get 20 psi of boost. Its nice like that because i have alot of control over it. I have my transbrake set at 8 psi of dome so I know im leaving on exactly 8 pounds of boost and I have it ramping up to 20 psi in the dome pressure table so I know im not blowing the tires off when 20 psi kicks in. We just played around with the regulator on the vair tank until it matched exactly 1v1.
I would imagine back pressure plays a role as well, your setup will have more back pressure than mine so you may need the extra pressure.
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From: Louisiana
your misunderstanding what im saying, im saying when I go into holley at set my target dome pressure at 20 psi it gives me exactly 20 psi of boost. That is not what my regulator is set at, Id have to look at my regulator to see what its set at. I dont remember off the top of my head.
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From: Louisiana
or should I say ive never tried with the vair tank and dome pressure sensor. I initially had one mac valve but when we switched to holley and added the tank we added the second mac valve and dome pressure sensor.
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From: Louisiana
why would I lie about that? I assure you whatever I set my dome pressure at in holley thats what my boost level is. My tuner helped me set everything up and its on the money. Keep in mine i dont have exhaust, I have a 4 inch fender exist.
Joined: Apr 2006
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From: Grand Rapids, Michigan
Okay, I understand now. As a general rule (in a perfect world) your dome pressure would add to whatever your spring pressure is, but it never seems to work that way. I have a 6 lb. spring, but even with 23 PSI of dome, I only hit about 18 PSI of boost. And I likely do have significant backpressure. So in @Tommy42088 's case, his dome just happens to equal his boost, which is what he meant by the 1:1 ratio.
Okay, I understand now. As a general rule (in a perfect world) your dome pressure would add to whatever your spring pressure is, but it never seems to work that way. I have a 6 lb. spring, but even with 23 PSI of dome, I only hit about 18 PSI of boost. And I likely do have significant backpressure. So in @Tommy42088 's case, his dome just happens to equal his boost, which is what he meant by the 1:1 ratio.