Supercharger Running Lean

I have a 2015 FFV with the following:
TVS1900 Magnuson
DW650cc Injector
2.30” Griptec pulley
Doug Thorley headers + Mid pipes
Dirtydeeds 10” Exhaust
Walbro 450 fuel pump
Bypassed the oem switching valve to run directly to the fuel rails @ 60 psi

The back story: I originally had the regular TRD supercharger kit installed paired with the Walbro 450 fuel pump. Everything was fine, AFRs were 10:1-11:1 at WOT, idle and cruise stayed around 14.7:1. That was until I decided to upgrade to a smaller pulley, bigger injectors, and headers.

This is where the problems starts.. tuning the truck became a nightmare and went on for a ALOT of revisions trying to chase down the issue. I would be rich the first few 2 pulls but start seeing 12-13 afrs the next 2.


After adding more and more fuel via the tune (usually via maf table but then later with multipliers in Performance enrichment after maxing out the maf table)… however after maxing both maf and PE tables the scans continued to show similar and sometimes even more lean AFRs especially in the higher rpm.


The tune was scaled (increasing injectors flow and reducing the maf table) by 10, then 20, then even 30% in an attempt to get the fuel needed for 4500rpm + to be in the mid to high 11s AFR and repeatedly saw no significant lowering of AFR under high load.

I took it to a shop to have it diagnosed, they supposedly checked for all vacuum leaks, and replaced my fuel pump and strainer. The problem still persisted so I also changed my fuel pressure regulator yesterday. With all the things the shop did and me changing the fuel pressure regulator(not sure if it did anything) my AFRs seem to be more consistent now but still in the 12s even with a ridiculous amount of fuel added.

Sorry for the long read but I’m lost now and wondering if anyone has anything I can take a stab at

 

Simple questions to start...
Is your alcohol percentage 0 (reset)?
I'd confirm fuel pressure at the rail with a manual gauge
Fuel tank over 1/2

 

What’s a good way to check for fuel pressure? To my knowledge there isn’t an easy way right? Although the shop told me originally I was only seeing 45ish psi.

 

This should be in the Super Charger thread.


https://www.tundras.com/threads/general-supercharger-thread.85513/unread

 

I'm currently running 2650 with stock FFV FP, 60 psi jumper with boost referenced FPR, 76mm pulley and 750cc Prospeed injectors. With the 750 cc injectors im damn close to maxing Inj DC and I'm at 5000'. I also have been chasing from lean to extremely rich A/F's but found my MAF sensor to be fubared from an over oiled K/N filter. What's your Inj DC values look like up top?

 

Also keep in mind like @VWTim said, my eth content was in the 35/39% range. I had to use techstream to reset to 0. Also, in HP for FFV ECUs they're many alcohol Composition tables that will need changed and matched up through percentages to keep things consistent. A lot of these are found in your timing advanced and retard tables and throughout.

 

Check the SC thread, I just posted about the gauge and tap I use in the past couple days. Easy drop in.

 

What form of tuning are you running? If it's HP Tuners you can send it over and I'll check it out snivspeedshop@gmail.com

I didn't entirely follow your methodology for adjusting fueling by maxing out the MAF? That should've been done via power enrichment, though maybe I misunderstood.

 

I’m daddymgm on IG, we’ve been at it haha I’m the guy that keeps running lean!

 

Agreed that the ethanol content % is the first thing to check before pulling your hair out with further troubleshooting!

 

My ethanol content is 0%

 

INJ dc 92%

 

If eth is 0 and injDC is 92 then those are off the plate. Are all of your Alcohol Composition set the same throughout? What does your COTS tables look like?

 

Also just to throw it in there the headers that are installed are absolutely sealed up? I'm assuming so but any leaks will throw off A/F which I'm sure you're aware of.

 

Actually you're 92% Inj DC at what A/F ratio? 12's?

 

Yeah. And to your other reply, I don’t feel or hear any exhaust leaks. I know I have one after the o2 where the mid pipe and cat back connects but I don’t think that’s the issue.

 

What's your Inj DC when you're in the upper 10's?

 

What part # walbro 450 did you use? Is it the 274, or the 267 which retains the jet pump? If you did the 274, did you drill holes in the basket?

 

the 274, and I didn’t drill any holes

 

I don’t have an FFV, so going strictly off of what Matt Smith has said before on Facebook. That said this may be your problem. The 274 eliminates the jet pump as I’ve read, which fills the basket under normal circumstances. Some people drill holes in the basket with the 274 to help it fill back up with fuel fast enough, but this is supposedly not the best way to use a 450lph pump in an FFV basket. Matt Smith says the pump to use is the 267, which is a direct drop in into an FFV basket and retains the jet pump to keep the basket full of fuel. I’m guessing you’re emptying the basket in the first couple runs and it’s rich enough, and then it becomes a problem for subsequent runs.

 

At this point I’m totally down with buying another fuel pump hahah but I’ve talked to a couple guys that run the 274 with no problem…

 

Im running the 274 with the jet pump still.

 

Well, like I said I’m not actually familiar with the whole FFV canister/fuel pump situation but I was always under the impression the 274 has to eliminate the jet pump, and the 267 did not based on comments I had read. I’m just regurgitating info, but I don’t have first hand knowledge! @e30cabrio may be able to speak to the 274/267 and the jet pump, not sure which he had installed. I know @Mdl used the 267 in an FFV canister, perhaps he can also chime in.

 

Fuel pressure will diagnose if that is the issue, no need to throw parts at it. Aftermarket fuel system take your pick on part no matter what brand are hit and miss quality. You can watch AFR for what happens after fuel pressure drops, but…

 

I’ve replaced the pump already. I’m gonna hook up a fuel pressure gauge

 

100%

 

Don't love the 90%-100% either

 

That's your target. 100% in the upper 10's you want 10-10.5 for max per @Mdl, your running outta injector. I hit 97-98% when im in the low 9's and 80%@10-10.5 range when tuning MAF volt/PE

 

So the injectors doesn’t want to hit 100% all the time? What could be the problem?

 

I can not find it for the life of it for some reason