On Fuel Rail Pressure...

stripSHO

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If you know the risk you also know what to look for when using meth heavy. Torrie was so good when I was trying out things with the car being not confident with it and changing things up on the meth setup. Luis knows the time and money I have invested and that is part of the reason I haven't done much with it because the hours have burnt me out on the car.. most tuners just say go and do this and don't explain to the new kids, things to watch. Things to monitor, and lastly common sense of the system.. with all these videos of people wanting follows maybe make one on meth and Maintenence.
Meth is great for cooling/cleaning, not a fan for aux fueling however. Too many variables that Matt outlined.
That is the difference in my mind. A normal kit for cooling/cleaning and a bump in power is cool. I should probably have one on my car.

However, when you are adding direct port or more nozzles in a attempt to make up for lack of traditional fueling (which isn't you) I don't feel comfortable about it. I know that was common place back in the day because we didn't have upgraded injectors, HPFP, and LPFP. However there really isn't an excuse anymore. If you cant afford at least the upgraded fuel pumps then you shouldn't be wanting to make bigger power. That is when I draw the line. Using a meth kit as a band aid as a aux fuel system is exactly that, a band aid.

Meth is like nitrous to me. There are many variables on how the systems work. Lose a fuel/meth pump, a fuel solenoid fails, ect bad things happen when the tune is completely dependent on that extra fuel to perform correctly. 9 times out of 10 the upgraded fuel pumps will be less expensive then a melted motor when a aux fuel system component fails. I mean I see used pumps going for a grand on FB groups. I was lucky when I got mine for a extremely fair price with extremely low mileage.

However Andrew you are not the average owner. You are different and your goals are different then the average Joe that wants to save some coin and be completely dependent on meth kit.
Plus side though like how Brad set up my non dependent AO tune is when the meth hits I get probably a easy 30hp bump, but even with meth off or failure, which I had once, the car reacts instantaneous, no concerns this tune will fail my engine. I have the HPFP and the Deatschwerks DW300C LPFP, and I'm keeping the meth. Cleaning and easy HP with no downside. I'm with you on being dependent, to much of a worry for me. but to each their own.

I don't see how the potential failures of a meth system are any different or worse than the myriad of potential failures in a conventional fuel system. If you get a single clogged or stuck injector the results are going to be much, much worse than a meth pump failure.

The opportunity to have a failsafe heavily meth "dependent" tune exists. It just requires a small amount of outside the box thinking to utilize the ECU's functions properly.
 

stripSHO

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Yeah I noticed the same thing with cold days. The air density, when it's cold, really works over the turbos.
I believe we're talking about different things. It is normal to see less boost in colder weather. The ECU is aiming for specific air loads, and as air density increases in cold weather it takes less pressure to move the same air mass, so the ECU requests less boost. You will see lower WGDC% and/or throttle angle in lower DA.

What I was referring to is that I see significantly less boost (roughly 1.5 psi less IIRC), even at lower DA and higher WGDC%, when I'm running 27 degrees of timing vs 15 degrees or whatever. The higher timing is more efficient and lowers EGTs, resulting in less energy available to drive the turbines.
 

SHOthyme

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I believe we're talking about different things. It is normal to see less boost in colder weather. The ECU is aiming for specific air loads, and as air density increases in cold weather it takes less pressure to move the same air mass, so the ECU requests less boost. You will see lower WGDC% and/or throttle angle in lower DA.

What I was referring to is that I see significantly less boost (roughly 1.5 psi less IIRC), even at lower DA and higher WGDC%, when I'm running 27 degrees of timing vs 15 degrees or whatever. The higher timing is more efficient and lowers EGTs, resulting in less energy available to drive the turbines.

Does that mean running more timing vs. higher boost is better, or is it more of a statement, that as you add spark you will see less boost?
 

stripSHO

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Does that mean running more timing vs. higher boost is better, or is it more of a statement, that as you add spark you will see less boost?
Well ideally you want both if you're trying to make the most power. In my case it wasn't really a conscious trade-off decision as I was already working at the limits of the fuel system. It's just something I noticed after-the-fact. On pump gas you will definitely find a point where raising the boost provides no benefit because you then have to remove timing to prevent knock. In that situation it's better to back off the boost and keep the timing.

For longevity, it should be noted that extremely advanced timing is more stressful to the top end of the engine. For a given BMEP, more boost/less timing will generate a softer and broader pressure curve in the combustion chamber. Less boost/more timing causes higher peak pressure but for a shorter period of time. Picture giving your piston a gentle tap with the momentum of a 5 lb sledge hammer, vs swinging a 5 oz tack hammer at it with all of your might. But on the opposite end of the spectrum (all the boost no timing) you have extreme amounts of waste heat that can melt cats, burn valves, cause overheating, pre-ignition, etc.
 

Bluezone

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I believe we're talking about different things. It is normal to see less boost in colder weather. The ECU is aiming for specific air loads, and as air density increases in cold weather it takes less pressure to move the same air mass, so the ECU requests less boost. You will see lower WGDC% and/or throttle angle in lower DA.

What I was referring to is that I see significantly less boost (roughly 1.5 psi less IIRC), even at lower DA and higher WGDC%, when I'm running 27 degrees of timing vs 15 degrees or whatever. The higher timing is more efficient and lowers EGTs, resulting in less energy available to drive the turbines.
Gotcha. I was just simply referring to the fact that colder air is denser, so more weight, more work. So yes you need less boost pressure to achieve the same air volume Target. Definitely talking about two different things. Similar but quite definitely different. LOL. Apparently after rereading this I had it wrong. Thanks.
 
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DadMobile

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Yeah sure, you can open a log and say "whoa that's ****** up" but saying it doesn't make it so. Show me where the car leans out, show us in the MPH trend where it stops accelerating, or show us any sign of misfires. Then tell us all the troubleshooting steps you and mystery owner went through to rule out mechanical deficiencies. I went to great lengths to show precisely why what you showed means nothing at all. I'm educating the wrong guy, but only because you are unable to learn.

As far as a race goes, probably not. Let me know what event you're talking about and maybe I can make it but my schedule is quite lacking in spare time. I was gonna do it if you were coming all the way to Milan, not because I think I can win but because I wanted to see if you're really so sissy that racing a bone stock SHO is your idea of a challenge. You've sufficiently proven my suspicion, so no need to go out of my way for it.
How am I sissy? I’m willing tune to my car and meet every condition you asked for a race. You can have back tire, hit, the entire 60’. I don’t care if I win or lose ‍♂️.

If I’m willing to drive 13 hours you won’t drive a couple to meet up and race?

Keep rolling the personal insults at me they will never work.
 

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