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So after weeks of dealing with leaking AN lines and whatever else could go wrong I've finally be able to start beating on the car/working on the tune. I'm a newbie when it comes to tuning and turbo troubleshooting.
So the car hauls the mail until around 2.9lbs of boost then it falls off. I did a boost leak test and found a couple fittings that didn't get thread sealant. A couple of theories i've came up with are,
1. Since I'm using the compressor to feed the dual mac valves instead of C02, i'm commanding 5lbs on the dome but I'm not even making 5lbs and by the time I have psi to put on the dome the wastegate is already opening (not sure if that all equals out haha)
Another thing what should my timing table look like? At 0psi i'm at 27* and pulls .75 - 1* per psi. Is that too high? I'm eventually gonna have it professionally tuned before it gets turned up but just for now on low boost.
Gen 3 5.3
7675 precision turbo
Terminator X Max
Pump 93
Without a log, mostly all we can do is guess, but unless you got some of the counterfeit spark plugs (there are tons out there and they look almost identical) there is no way you are blowing out spark. If your timing is correct with what the computer thinks you have, that is not the current issue. That leaves fuel and actual boost. You need to verify fuel pressure under load and AFR, and if those are good then start looking for boost leaks or wastegate problems.
Has a Magnafuel 1:1 Regulator with base pressure at 60psi roughly so fuel pressure should be correct if im seeing that right. Afr was a little off from what I was commanding but not something super high.
By falls off do you mean you lose the 2.9 lbs or it just doesnt make anymore?
Are your mac valves plumbed right? Dual valves without co2 just seems overly complicated...
what boost does it make without any boost control in the way?
It will hit around that 2.9lbs and then lose power with my foot to the floor. Yeah I was setting myself up for getting a co2 setup just haven't gotten to it yet. Had the same issue with the boost control turned off.
3 lbs. on a 4.5 lb spring doesn't sound too far off, it's not a 1:1 ratio with waste gate springs.
A 5.3L on 3 lbs. isn't going to set the world on fire my friend, the turbo is barely even working at this point.
Keep the timing NA until 1-2 lbs. then start pulling it out, get it making 10 lbs. w/ 16 degrees and it'll wake up.
3 lbs. on a 4.5 lb spring doesn't sound too far off, it's not a 1:1 ratio with waste gate springs.
A 5.3L on 3 lbs. isn't going to set the world on fire my friend, the turbo is barely even working at this point.
Keep the timing NA until 1-2 lbs. then start pulling it out, get it making 10 lbs. w/ 16 degrees and it'll wake up.
Yeah I knew it wasnt like an exact number, so basically just throw some stiffer springs in and stop worrying so much haha
Plumb it with a single solenoid for now and see if you can make more boost until you get your co2 setup. Or add spring.
When I got my first turbo setup goin I only had enough spring for a few pounds then the wastegate opened and the car got loud and didnt really go fast...same kinda feeling as what youre describing
Plumb it with a single solenoid for now and see if you can make more boost until you get your co2 setup. Or add spring.
When I got my first turbo setup goin I only had enough spring for a few pounds then the wastegate opened and the car got loud and didnt really go fast...same kinda feeling as what youre describing
Yeah that's what is happening you can hear the dump tube start screaming haha. I have enough springs for 25lbs supposedly so i'll try bumping the spring up a see how it goes
Using compressor "charge air" is not ideal for a Mac valve deal. Pressure to desired boost isn't linear. Very little chance your experiencing spark blowout a 3psi, like zero.
No i'm using the turbo to feed a dual mac for the time being. Switching to co2 when i get everything worked out
compressor discharge should be running to the bottom of your wastegate, your pressure source(intake manifold and/or compressed air should be running to one side of the mac valves and the t in the middle runs back to the top of the wastegate with the other side of mac valve to vented air. If your wastegate has a second point on the top that is where I would install a dome pressure sensor since your only holley and can easily control it. Get a sensor from low dollar motorsports.
compressor discharge should be running to the bottom of your wastegate, your pressure source(intake manifold and/or compressed air should be running to one side of the mac valves and the t in the middle runs back to the top of the wastegate with the other side of mac valve to vented air. If your wastegate has a second point on the top that is where I would install a dome pressure sensor since your only holley and can easily control it. Get a sensor from low dollar motorsports.
Currently off my turbo it hits a T one to bottom of wastegate and one to feed the mac. Yeah I have a lowdollar dome sensor but it is remote mounted. It's looking like a co2 bottle with a auto shutoff valve is the move
Currently off my turbo it hits a T one to bottom of wastegate and one to feed the mac. Yeah I have a lowdollar dome sensor but it is remote mounted. It's looking like a co2 bottle with a auto shutoff valve is the move
Or an air compressor, I run a Viair setup in my car currently and it works fantastic.
Plus, I can always air up my tires at the track if needed and it never needs filling.
Currently off my turbo it hits a T one to bottom of wastegate and one to feed the mac. Yeah I have a lowdollar dome sensor but it is remote mounted. It's looking like a co2 bottle with a auto shutoff valve is the move
I have a Viair tank, my boost levels never stayed level before this, depending on weather conditions I would always see different levels of boost. Your setup isn't that hard to change, if you dont have a port on your intake manifold to use as a pressure source then get a distribution block and run your brake booster hose in/out and then use one of the ports on the bottom as your pressure source. Look on holley page and they show you images of how to do it. The show you best, ok, and bad. Mine is setup like the one that says best.
When I was first sorting out my car, my power tuner noticed I had put 3 lb springs in the WG. Since I didn't give him the other springs he just took off the WG reference to see what it would make boost wise with RPM. Mine would make 14 psi at 7100.
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Turbo 5.3 Boost Falling Off 
