return fuel system help

thelonebean

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I'm thinking of doing a return system install myself instead of paying a shop for labor. Only problem is trailering it after install for a tune. I know coyote guys lock the fuel pressure regulator at 48 without boost reference, with the same injectors and don't need a tune to account for it. Can I do the same thing if I lock the regulator to 42.8 or whatever pressure it is for 2v's? If anyone knows if I can please let me know, thank you
 

365 Saleen

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If you drive it without going into boost you should have no problems. Just drive reasonably.
 

DSG2003Mach1

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My tuner told me where to set the regulator and sent a tune for it so I could do a test drive, get on the trailer etc… not a big deal
 

thelonebean

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My tuner told me where to set the regulator and sent a tune for it so I could do a test drive, get on the trailer etc… not a big deal
that may be a problem cause I don't have a tuner and the people I messaged for a tune said I needed to bring them the car with no plates on it and on a flat bed... can you tell I live in cali?
 

DSG2003Mach1

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that may be a problem cause I don't have a tuner and the people I messaged for a tune said I needed to bring them the car with no plates on it and on a flat bed... can you tell I live in cali?

ah, well ya that blows.

if its gotta be towed in then maybe you dont need a start up tune. Once a tuner is picked I would think it wouldnt be a big deal to get a start up tune, might want a deposit toward the tuning work for the start up tune
 

01yellercobra

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Depending on how nuts you're going it might be worth tuning yourself. It's nice not having to worry about how you're going to get it taken care of.
 

thelonebean

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Depending on how nuts you're going it might be worth tuning yourself. It's nice not having to worry about how you're going to get it taken care of.
I’ve been debating on just tuning the damn thing myself cause It’s just so much more simple and cost effective. You think hp tuners will do the job?


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01yellercobra

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I’ve been debating on just tuning the damn thing myself cause It’s just so much more simple and cost effective. You think hp tuners will do the job?


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I've never used HP Tuners. I've heard good things about it. But I'm not sure how well it supports our cars. I'd look into @decipha's set up personally.
 

thelonebean

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I've never used HP Tuners. I've heard good things about it. But I'm not sure how well it supports our cars. I'd look into @decipha's set up personally.

I’ve been looking for someone like him for a while to do remote tunes. Definitely something I’m going to look into. Are you or anyone on here tuned by him?


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decipha

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Why are you swapping to return?

hptuners doesnt correctly support the older ecus at this time, maybe one day. Regardless, hpt, sct or any of the commercial tuning options are not going to pass emissions, not to mention their support for those older vehicles is extremely limited.

coyote comes stock with a return style fuel system, the stock regulator is mounted in the tank (pprv) and should be 58psi-65psi on gen 1 and 2. Gen3 is dual system usually with 65psi on DI regulator and 40psi on regulator for rail injectors when people go aftermarket fuel system.

Coyotes infer manifold vacuum to compensate for changing vac and boost pressure. 2V doesnt since it has the fuel rail pres sensor that does it for it.

If your only swaping from returnless to return and leave the fuel rail pressure sensor intact and functioning then your tune wont be affected assuming it was tuned properly.

Keep in mind without a manifold reference line hooked up to the regulator you will loose 1 psi of injection pressure for every lb of boost keeping the injectors shut.

Also if you hadnt yet, you should use the original fuel pump output to trigger your new fp relay as well so it primes and shuts off correctly.
 

thelonebean

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Why are you swapping to return?

hptuners doesnt correctly support the older ecus at this time, maybe one day. Regardless, hpt, sct or any of the commercial tuning options are not going to pass emissions, not to mention their support for those older vehicles is extremely limited.

coyote comes stock with a return style fuel system, the stock regulator is mounted in the tank (pprv) and should be 58psi-65psi on gen 1 and 2. Gen3 is dual system usually with 65psi on DI regulator and 40psi on regulator for rail injectors when people go aftermarket fuel system.

Coyotes infer manifold vacuum to compensate for changing vac and boost pressure. 2V doesnt since it has the fuel rail pres sensor that does it for it.

If your only swaping from returnless to return and leave the fuel rail pressure sensor intact and functioning then your tune wont be affected assuming it was tuned properly.

Keep in mind without a manifold reference line hooked up to the regulator you will loose 1 psi of injection pressure for every lb of boost keeping the injectors shut.

Also if you hadnt yet, you should use the original fuel pump output to trigger your new fp relay as well so it primes and shuts off correctly.

I’m swapping to return because my stock fuel system is kinda maxing out the duty cycle with my procharger and I wanted room to grow for the future and be able to run e85. As you could probably tell I’m not very familiar with tuning software for my vehicle, I’m sure you know much much more than me but I was just throwing out an example of one without going balls to the wall and getting a Holley dominator and learning there. I was also planning on keeping the fuel rail pressure sensor in tact because that’s what I use to monitor fuel rail pressure on my x4. I kind of figured that locking the PSI wouldn’t be good because for the reasons you said above, just was an idea. You think I could hook up the reference line and be fine to start it then? Good advise to use the same trigger for the new pumps as well, probably would be the best method.


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decipha

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You can swap in two stock coyote fuel pumps and two stock fpdm's and support all you need to on E85. No need in downgrading to return.

If all your doing is swapping pumps and fuel systems then you can run perfectly fine on the tune you have no problem.
 

thelonebean

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You can swap in two stock coyote fuel pumps and two stock fpdm's and support all you need to on E85. No need in downgrading to return.

If all your doing is swapping pumps and fuel systems then you can run perfectly fine on the tune you have no problem.
thank you for the great info. much appreciated
 

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