TRD/ Magnuson 4.0 Supercharger Tips, Tricks, and Mods

Do you know what the max reading on the stock MAF is?
I just captured a couple logs. Hit 46.68lb/min, 5.00V at 5700RPMs. It had already peaked by 5500RPMs. Assuming 5V is the top of the scale.
It's around 20F, hit 9.19psi.

 

42.843 lb/min is factory MAF mass airflow with the OE airbox @ 5 volts.

5 volts is you maxing out the MAF/housing.

I’d recommend using the Subaru MAF (with proper rescaling) before going to a larger diameter housing.

 

OK, thanks for the facts. Do you expect additional gains if I also swapped to the 70 or 76mm T.B.? I know there was some measurable gains on the Dyno with the NA application.
And what type of set up would you recommend if I were to add a Meth system in regards to tuning?

 

With the long restrictive inlet to the compressor on the TRD/Maggy blower, I'm sure their would be some gains for the larger TB, but I don't know that going much larger than 70mm will net you much unless you address the restriction between the TB and compressor.

With these trucks (and them being trucks) I'm not a fan of creating a tune specifically for use with Meth. What happens if you have an issue with the system or simply run out? I'd prefer to keep the tune configured for the base fuel you intend to run and then use the Meth as a safety net. If you want dyno numbers for a pretty sheet to brag about, that's one thing. But for daily/general use, I'd personally advise against a dedicated Meth tune unless you always have the laptop with you and are monitoring data to verify your system is functioning properly.

 

100% tuning with meth needed 24/7 is asking for trouble. However on that note I was recently setting up a Megasquirt on my buddies supercharged GTI. He had bought an Innovate dual wideband/boost gauge for it. It came with an extra relay that runs off the gauge that you can program as a safety circuit based on AFR and Boost pressure readings. You could use that trigger meth spray if things started going bad under load? AFAIK the meth kits are only lookin at boost level? Never looked that close at them myself tbh.. Kind of got my wheels turning though, since the majority of SC/Turbo folks are still running on the OE ECM you could probably use such a device to push the limit a little more safely?

 

Well boys and girls…

 

I have the innovate PSB-1 and you can wire it to a solenoid that will open and release all boost if boost/afr go outside of the set parameters. On a previous build I used a FailSafe on my Snow Performance water methanol to open a solenoid if the flow dropped off.

I’m with JustDSM on my FJ Cruiser though, I have his tune and added water methanol afterwards for added safety, cooling effects, and keeping the valves clean over time! My Stage 3 water methanol is progressive based off boost and pulse width at the injectors.

 

I like this idea. How are you intercepting the Inj duty cycle?

 

The controller has two wires that run through the firewall and are connected to one injector using two PosiTaps.

 

What are everyone's suggestions for reviewing the drop in MPG on my truck? I finally got my axle replaced. While I was at it, I had a new steering setup installed and the AEM 320 Fuel pump.

I have been used to lousy MPG, but I am getting maybe 50-70mpg on half a tank on the street, which is very bad. 7-8 mpg I could see aired down in the dessert but not just driving around. I did see some evap issues recently but haven't seen them since. I had the shop who helped me with some work, and they noted they pulled the tank but did not see any issues. Assuming they did, putting it all back up may have fixed that without knowing.

@SUMOTNK and I changed out the Plugs and added some RIPP coil packs not that long ago (Mileage). This was before all the RIPP issues. If I pull them, I'll probably replace them back to stock. I did put the Ruth Plugs in then, but I had no issues running those.

I haven't been driving the truck as much with continued issues and itching to take it on some longer trips soon but not with this kind of mpg.

 

any other weird running conditions? High idle?
I know me and a few others are running the ruthenium plugs without this symptom…

Do you have a specific date or mileage this started happening? Anything changed just prior?
Maf cleaned?
Fresh air filter?
No leaks in the fuel stystem up to the in the injectors themselves?
You just replaced an axle — front? All four wheel hubs spin free and not binding or super stiff? (More likely just loose and sloppy)
O2 sensors good?
Possibly even a tune that’s running wonky.

I am no expert on the intricacies of Tacoma’s, or even Toyota, but this is everything I could think of.
I do techline for a motorcycle company, most of the poor MPG issues we see involve leaky injectors, poorly set up throttle bodies (ecm and the butterfly valves don’t know where they really are at), and sometimes even a corrupt flash onto the ECU.
Most cases exhibit Rich running conditions like high idle and boggy throttle response too.

 

It seems to drive normally for the most part.

Main things recently changed:
1. Rear Axle - swapped stock for a Tundra Diamond Axle
2. JD Howe Steering Kit installed.
3. AEM 320 FP installed (only thing technically that touched the fuel system)
4. Front Diff was also replaced since I had to re-gear the truck.
5. Front Engine has small spacers added to the engine mounts to clear the Tundra Rack.

I think that's the main things. Other things were structure related like box rear frame.

Before that was done, I only swapped out the AFE Dry filter for a Stock 4runner paper filter (as I was getting too much silt getting through).

I ran Ruth's 5k miles without issues, so I don't think that would be it.

It's possible the O2s. I haven't really looked into those, but the O2 for my Wideband def is toast as it's not reading correctly. I haven't checked my regular ones, but I am getting reading ones that are in line with what I have always gotten.

I am overdue to have @JustDSM review my tune, but I wanted to get more things resolved before consulting there. I have had the same tune on the truck for the past few years minus some back and forth for smog checks.

My initial thoughts are: tires, changing the oil (only as it was sitting for a bit), and getting my wideband O2 replaced. I was debating taking the Ruths out, but they were fine. I also debated swapping my FIC back to the S/C TRD injectors, but I haven't had issues before. When I swapped the Ruths, my seal inside the S/C (orange deal) was toast, so I removed that. Maybe add that back.

I was really thinking the Fuel pump as that was the only thing related to fuel that was updated but chimed in here before and folks didn't think so (was related to getting evap codes) but that hasn't popped up recently.

But honestly, I'm just guessing. Personally, I have not run into fuelling issues or MPG issues like this before, but it's a game to test.

What should I test or look for to test the Factory 02's?

Is there any other way to test leaks in the fuel system beside a smoke test? I did have some hunches that I could be leaking fuel.

I did notice this today on the edge of the S/C. It could be nothing, but it seems like some type of residue.

Game for any suggestions or tests to run or see if I can run them.

This week, I plan to:
Swap oil/filter
clean MAF
Check Airfilter (should be spotless)
Update Wideband O2

 

@nudavinci64 , don’t overthink it. If this happened right after you made changes, something you did is likely the cause.
Other things to consider:
Take it for a drive with a scanner. This will quickly rule out issues with MAF & O2’s. Also, if it is staying in open loop. Faulty temp sensors sometimes cause this by reading cool, and thus rich mixture.

 

Didn't you re-gear to 4.88s?

 

Hypertech or any speedo calibrator? @nudavinci64

 

Don't forget it's the season for the gas blend to change. I would also check for small vacuum leaks.

 

Could be a nothing burger but this jumped out at me:

2. JD Howe Steering Kit installed.

Doesn't the new steering pump run full pressure all the time? This would be a parasitic loss on the engine all the time, vs the stock one that only ramped pressure when needed, including the factory bump in engine rpms when steering input is at idle. Again, I could be totally wrong in concept.

The other thing that was mentioned, gearing - regear helps when the truck is undergeared - removes the lost fuel due to overtaxing the throttle just to get the truck rolling. but overgeared for the power will also just spin the engine faster which I think could in some scenarios result in reduced milage depending on the load the engine sees.

 

Yes front diff and axle but were talking single digits here.

Yes def thinking related but with my luck its something else that popped up the same time.

 

I'm unsure about the steering kit. Havent heard anyone having issues with it.

Regear I was running 4.56 for years without much issue and only had to regear again since the tundra axle could only be in 4.3 or 4.88, but I would not expect single-digit mpg on DD driving.

 

MPG started well in the summer time, so I don't expect seasonal gas to be any factor here. Yah curious of any leak that could cause it but stuck where to look.