Gen3 swaps and fuel pressure

[lxmodguy]

Hey Folks,

It seems like at least 5-6 times a month I have someone approach me about tuning their swap because it surging or sputtering. These are almost always the folks with the corvette regulators. First off, fuel pressure is very important when tuning an EFI setup. You can't just grab a regulator from something else because it is cheap and expect it to work with your stock ECM tuning. Second, if you aren't extremely familiar with EFI either buy a self tuning EFI setup or buy a crate motor with an ECM pre-tuned......then leave it alone. Third, if that isn't an option message me and I will give you the name of a qualified gen3 hemi tuner in your area. Don't take it to a chevy shop.....it is not an LS motor and you will be sorely disappointed with your results if you do.

Sorry for the rant/commercial, but I thought it was important to share this as it is becoming a more than weekly occurrence that I get an email asking for tech support. I don't mind helping member, I think that is what the community is all about. I am just not on here as much lately and wanted to make sure to squash this one issue in particular.

 

[Sixpactogo]

Hey Folks,

It seems like at least 5-6 times a month I have someone approach me about tuning their swap because it surging or sputtering. These are almost always the folks with the corvette regulators. First off, fuel pressure is very important when tuning an EFI setup. You can't just grab a regulator from something else because it is cheap and expect it to work with your stock ECM tuning. Second, if you aren't extremely familiar with EFI either buy a self tuning EFI setup or buy a crate motor with an ECM pre-tuned......then leave it alone. Third, if that isn't an option message me and I will give you the name of a qualified gen3 hemi tuner in your area. Don't take it to a chevy shop.....it is not an LS motor and you will be sorely disappointed with your results if you do.

Sorry for the rant/commercial, but I thought it was important to share this as it is becoming a more than weekly occurrence that I get an email asking for tech support. I don't mind helping member, I think that is what the community is all about. I am just not on here as much lately and wanted to make sure to squash this one issue in particular.

I guess I'm one of the guys pissing you off by asking questions. I bought my complete kit from Bouchillon Performance and the Corvette style fuel regulator was part of the kit. I was assured that they are Mopar people and know what they are doing. Since I didn't know what the hell I was doing, I bought into it. I have since found out that they don't have all the answers either and so now I'm left holding the bag of ****. Sorry for asking questions. I will figure it out on my own.

 

[5.7 hemi]

I do believe that if you run a stock programming, the vette filter/reg is fine. I've done/used it without issue on a stock programmed ecu. Now what lxmodguy is talking about, is the custom tuning side of the equation. You need to dead nuts on your pressure and the vette filter/reg isn't up to the task. I will defer all custom tuning and builds to lxmodguy, he does know his ****! So any member on here should not take what he posted in the wrong way, rather another piece of info to help.

 

[5.7 hemi]

Why disagree with what I posted?

 

[Sixpactogo]

I have the stock ECU with stock programming. I shouldn't need custom tuning. I've had issues with my computer from the git go and all I get from these so called engineers that think they know it all is everything but the correct answer. I admit that I know next to nothing about computers and so I'm at their mercy. What pisses me off is every one I quiz about something comes up with "Why did you use that? That is no good! You need this or something else" when they have no clue. I've had five engineers tell me that my high voltage issue was in my wiring or the battery or the ignition switch or the alternator. Everywhere but where I thought it was. In the computer where the regulation is created. Turns out, it was a battery temperature sensor that should have been defeated. Now I have surging issues at light throttle. I get everything from "your injectors are bad to your fuel pressure is low to your fuel pressure is too high. If that is not the problem, then it is in your throttle body or your spark plugs are mis firing". The thing runs like a scalded dog at full throttle! How can it be fuel pressure or bad plugs? Since I am computer illiterate, I have to dwell on common sense and asking questions. I suspect it is in the communication between the computer and the fly by wire because it feels like the butterfly is opening and closing at light throttle. Of course, I'm told by all these people that know their ****, to do everything but re-balance the wheels. It is probably all good info with good intentions but like I said, I will figure it out on my own or I will ask the question to the right person that has the correct answer. Now my rant is over too.

 

[5.7 hemi]

Wow! Sorry to hear you have problems with your set up. Can you give details on what you have, harness, computer year, engine year, etc?

 

[Sixpactogo]

Why disagree with what I posted?

I may have bumped the red X. Didn't do it on purpose. Sorry. He did say though, that you can't take a regulator from something else and expect it to work with a stock ECM tuning. Maybe that is the case but like I said before, I was told by Bouchillon that it was the way to go.
Guess I will find whether that is fact or fiction too.

 

[5.7 hemi]

They work just fine with stock programming, no issues with that. Where do you have it located?

 

[Sixpactogo]

I bought a complete kit from Bouchillon that was put together by them to run my 6.1 Hemi / 5R45RFE in my 68 Charger. Everything fit just fine and worked as it should except the damn computer. They use Hotwire's harness and they provided a computer I believe from an 05 Ram and have a Motorola guy re flash the computer to make it work with these kind of installs. According to them, they have never had a problem until me. Guess it is just my luck but now they won't answer any of my emails or return my calls.

 

[Sixpactogo]

They work just fine with stock programming, no issues with that. Where do you have it located?

Right frame rail just below the engine compartment.

 

[5.7 hemi]

I think you got s crap computer and Randy has a chip on his shoulder, kinda like little dog syndrome. Have you thought of getting another computer off eBay, 100 bucks. Then have stuff deleted.

 

[Sixpactogo]

It has crossed my mind many times. I have been trying to find someone that can re-flash the one I have. The Dodge dealers can't do anything with it. Maybe I will try Chris at Hotwire if I can't find someone locally that knows something about them. Like I said, I will get it dealt with sooner or later. Thanks for your help.

 

[5.7 hemi]

Chris can do it, hands down. The dealers won't mess with cause it isn't in a vehicle. Spend the 100 bucks or so, and send it to Chris. You won't be disappointed.

 

[kb67mopar]

Chris re-flashed mine for a good price. I run a 2004 Ram ECM but I am also running the manual transmission tune. My only issue is a surge after deceleration...I think it has to do with me not providing a vehicle speed signal to the computer. I think the computer uses that to determine where the throttle should be under light/no load conditions. I've yet to prove it as my give a crap level over it is pretty minimal...doesn't really bother me and doesn't affect much.

 

[Sixpactogo]

I spoke with Chris a couple weeks ago about sending him an ECM for re-flash. He told me before I spend the money on another unit, I should have someone with a good code reader get into the ECM and do a "electronic throttle control re-learn"
I have yet to find someone that can do that. The tech guy at my local dealership told me the the Mopar unit does not have adaptive strategy and that it uses initial voltage at closed throttle for a starting point and goes from there when dealing with the throttle control. I don't know if Chris knows something these guys don't or what but I am thinking about spending the money just for my own satisfaction since all the problems I have had with the ECM I now have. If a different unit makes no improvement I guess I will have look at the fuel pressure and or whatever else comes to light. It costs a lot of money to be stupid and that is what I am when it comes to all this new technology.

 

[Dreamcatcher]

So how much fuel pressure does it need and what then is the preferable pump to run. I was ready to pull the trigger and get all this stuff from Randy but now I am on hold. I want to do it right the first time.

 

[kb67mopar]

I was also told that if you turn the key on, (do not start) then slowly push the pedal to wide open and release, then key off, it will re-learn the throttle settings. Its worth a try...

 

[5.7 hemi]

Any pump that can do 58psi will be fine. An intank is preferable but not mandatory. Also use a return in the system as it will help the pump and your fuel will be cooler.

 

[Sixpactogo]

Before I pissed off lxmodguy, he told me the Hemi needs 58psi. I am not sure what the GM filter/regulator runs as I don't have a pressure gauge on it. According to Randy @ Bouchillon, it is what they use so that is what they supply. As far as I know it works fine but like I said, The jury is still out since I have a slight surging issue that I still believe is in the computer strategy but have not yet confirmed it for sure. The pump they supply is in the steel tank they provide. I forgot what the GPM is on it but it is supposed to be enough for up to 800 HP. It fits and works fine. If you get one from them though, the first thing I would do is replace that damm Chinese lock ring with a OEM lock ring. The China one is about 1/2 as thick and mine leaked.
Their tank has a 3/8 fuel line and a 5/16" return.

 

[kb67mopar]

Before I pissed off lxmodguy, he told me the Hemi needs 58psi. I am not sure what the GM filter/regulator runs as I don't have a pressure gauge on it. According to Randy @ Bouchillon, it is what they use so that is what they supply. As far as I know it works fine but like I said, The jury is still out since I have a slight surging issue that I still believe is in the computer strategy but have not yet confirmed it for sure. The pump they supply is in the steel tank they provide. I forgot what the GPM is on it but it is supposed to be enough for up to 800 HP. It fits and works fine. If you get one from them though, the first thing I would do is replace that damm Chinese lock ring with a OEM lock ring. The China one is about 1/2 as thick and mine leaked.

The service manual I have says 58 psi as well.