General Supercharger Thread

Thank you for sharing this information! Very useful.

 

They hide the good stuff deep in the TIS.

I was able to replicate the signals and “create” fuel info displayed on my bench top cluster.

The cluster has to be programmed to the stock injector flow rate and calculates fuel burned per cycle using RPM value if I remember correctly.

Bigger injector with more flow would definitely cause a false reading


Edit I take this back, my notes show the ECM calculates a fuel flow rate from the injector pulse, the ECM then passes the flow rate to the cluster to do the MPG calculations.

As mentioned tire sizes and throwing off actual distance travelled creates a problem also

 

In essence, we're unlikely to be able to correct this, at least easily. Oh darn, we'll forever be forced to use simple math if we wish to determine accurate MPGs.

 

Well I actually applied a linear scale to the data to run the 18 cluster in my 2007 truck. The new cluster is using a different math algorithm, so using my Arduino can gateway I add in a multiplier to the raw data from the ECU and then send it to the new cluster. I tweaked the adjustment factor to get it pretty close to my hand calculations.

I would say it’s as “accurate” as it was from the factory

 

That's just brilliant! Blows my mind...

 

Could be as simple as “the new injectors are 20% larger than stock” so add a 20% correction to the stock fuel flow data from the ECM before it gets to the cluster.

Make the cluster think it’s using more fuel than what the engine ecu reports because in reality it is.

Obviously this involves a man in the middle to interpret and modify the CAN message.

 

Totally logical, but figuring out the MITM part; understanding the communications, figuring out what's required to manipulate it, and coming up with a way in implement it. Excellent!

 

Question for the group! Having had the SC for all of 2 days now….am I missing out having the stock magnuson tune? I do have a mvi3 on the way, but am a bit scared to start messing with is seeing’s as another member almost bricked his ecu….

seems to hunt gears with the cruise control on but other than that seems good to me….guess my FOMO is kicking in? Will changing the tire size in the go tuner software help?

sorry for all the noob questions!
any info as always is appreciated!

 

Do you have ANY tune at all? Or are you running the stock tune, still? The latter could be very bad...

 

Sounds like he has the canned magnuson tune.

 

Have @snivilous or @JustDSM tune it and call it a day

 

Maybe I should learn how to read good...

 

Agreed.

 

We’re one of, if not the only ones who can provide custom Toyota calibrations for the RTD devices. Saving a ton on having to buy additional equipment and licensing. Just something to keep in mind.

 

Thanks for the replies. Yes it has the canned magnuson tune that “was included” with the kit

 

Definitely a lot of room for improvement over what Magnuson gives you.

 

Has anyone tried modifying the oem fuel rails? I was looking at a video Viktor made about pressure drops. He added a test port to the OEM rails for reading pressure. In this video he mentioned a drop in pressure after the fitting that feeds one rail to the next one. Would it be possible to have a larger fitting welded/or threaded to the rail in place of the skinny oem ones?

 

You can significantly enlarge the factory fuel rail inlets/outlets by removing the chamfer at the end of them.

 

Hey @ViktorG (or anyone else) what are your thoughts on adjusting shift line pressure for firmer shifts and less clutch wear? The TRD tune lowers the pressure, which seems counterintuitive, and I've seen some other people recommend bumping pressure up a little.

 

Keep in mind, you cannot modify the Magnuson tune you already flashed. You cannot download the Magnuson tune to adjust it. The tune you will "read" off the truck is the original OEM tune. This means if you change the tire size value and flash that tune you modified, you didn't tweak the tune you're currently running but reset back to the factory (non Magnuson) tune and changed the tire size. If you want to change away from the Magnuson tune you'll need an entirely new tune since you cannot tweak the Magnuson tune you're already running. When you "read" the ECU it won't give you the Magnuson file, HPT will give you the OEM file your ECU originally had instead.

 

Good info.

I see I need to do a bunch more tuning research so I can understand this^. I couldn't presently follow what you wrote.

 

I am not a full time professional tuner, but I max out the line pressure only at full throttle on my truck tune.

 

A little background from my end:

I picked up this '21 at auction. It has a salvage title. I rebuild all my daily drivers.

This truck is to replace my present 2008 as my primarily RV towing rig.

I have the green light from the war department to buy and install a M2650.

It takes me 2 years to put together a project-a little longer this time because of supply chain issues.

I know enough that I need a tune after the install. Beyond that, I'm a babe in the woods.

I appreciate all the tuning banter, but am not gathering everything that many if you are writing.

I short, please excuse my ignorance.

All I want is a little more HP for dragging the RV up the random steep mountain grades.

 

When you plug the MPVI into your truck and open the VCM Editor program, at the top is a button "read vehicle". If you click that, you'll download a tune. Even though it's called "read" you're not actually reading from the ECU. The tune you'll download is from the HPT servers, and not actually from your ECU. It doesn't matter what tune your ECU has on it, it will always "read", ie download, the same file your ECU came with from the factory. What this means is if you get a locked tune, such as the Magnuson tune you currently are running, you do not have access to modifying/editing that tune because you cannot access the file currently on the ECU (since you can't TRULY read the ECU, you just end up downloading a file from HPT based on your ECU identification).

So when you were saying, can you just update the tire size in the tune... yes you can, but the tune you're changing is the factory OEM tune, so none of the other tweaks for the supercharger will be part of that tune. The Magnuson tune is inaccessible from being modified. All you can modify is the stock tune or if a tuner sends you an unlocked tune. The Magnuson tune is locked, so you it's not as simple as "update the tire size on my current tune" since you can't modify your current Magnuson tune.

 

In short, Your tune is a file, without that file, you can't make modifications. As Snivilous said, the device reads your ECU calibration ID and downloads a compatible tune file for you to begin editing, if you write that file you overwrite the previous tune.

 

Also nice shop setup, I have an Atlas lift too but it's the floor mounted cables not the overhead. Best $2k I ever spent!

 

Before and after removing chamfer.

 

No shit!

About the same cost as a set of high end tires and wheels.

We ain't 20 anymore.

 

That's also where the IPT valve body or Transgo kits come into play. Your removing the shift overlap and increasing pressure for direct engagement. You are eliminating clutch slippage for certain gears. Most are 2-3-4 and you'll hear people talk about the whiplash from engagement. The overlap gives you the ease of entering each gear whereas the kits remove that so get directly intovthe gear with no clutch slippage, saving you clutch packs.
I'll be doing the Transgo kit this summer. Basically an IPT valve body but doing the work myself.

 

Is this enough balance out the “imbalance” in fuel pressure at the passenger side rail?