96 5vz xcab 4x4 TACO TURBO BUILD

The stock FPR should always be enough to handle 4 psi when the hose going to it is introduced to boost pressure on the manifold. If your WOT AFRs are anywhere over 13 at 4 psi then I would guess that your fuel pump is on its last leg.

 

At one psi or so (less) AFR's are around the 13 range, so maybe you're right.

 

So your turbo is all hooked up, but you don't use it? If your wastegate spring is 4 psi and your FPR is hooked up to a boost source, then WOT pulls for you assuming your injectors, FPR and fuel pump are all healthy WILL be below 12 AFR. I suggest getting on the highway and putting that pedal to the floor. It doesn't matter how much pressure your FPR is putting out, your ECU will trim your injector pulse width to satisfy a 14.7:1 burn in closed loop. Open loop only occurs in WOT

 

No I have used it, but open loop does not occur till somewhere after 1psi. Is that normal? Also will yours die after hard accel or boost? When coasting it has a tendency to die randomly...

 

No, open loop should occure the second you stomp on the gas regardless of what gear or boost level you're at. If it doesn't, then I suspect one or more sensors need to be replaced on your truck. A bad front o2 sensor mixed with dirty or bad MAF will cause the truck to die randomly. Where exactly do you have your MAF, and does the air make any drastic turns right before it travels through it?

 

Nope
And the MAF is brand new

 

Does it die right after accelerating and putting it in neutral? If so, then it's because you've pressurized your charge pipes (even if the boost gauge reads 0psi) and the air travels backwards when you close the throttle blade, causing your MAF to say "WTF?" and your truck stall. I've been there done that. Your o2 looks pretty new, but that doesn't mean it's not bad. Same with the MAF. Did you solder those wire splice spots? Are you getting any engine codes... even pending ones (no light)? Like throttle position codes or anything?
Do you normally have a filter on that MAF?

 

Are you running pure methanol or wiper fluid? And aren't you in Colorado? Ambient pressure is like 13 psi here so keep that in mind when you say methanol is enough to suppress detonation at 8 psi boost (not saying it isn't).

Glad to hear it's so fun though. I'll be running an 8 psi waste gate, no boost controller and a cooling mist progressive meth kit. I ran -25 F wiper fluid on my s/c for a bit and it was quite helpful. Not sure on nozzle size. I might try to use a much smaller nozzle and run pure meth though to increase my refil intervals as I tended to burn through 1 gallon in as little as 50 miles.

 

My intake manifold feels like I just took it out of the refrigerator after a long and hard pull... It is safe to say that detonation would be pretty much non-existent assuming you're using high octane gas and your WOT AFRs are in the 11s even at sea level at 7-8 psi. Many professional tuners will ADVANCE timing without methanol to increase the power of a stock setup that is already at or above 8 psi from the factory.
I'm using 20- washer fluid because the water vapor alone adds octane and knock suppression while maintaining a superior flash point from a safety standpoint that pure meth will not do for you.
I plan on adding 2 more nozzles and going no bigger than 2gph on each to ensure finest possible atomization and even delivery to each intake runner

 

Solder yes. No codes not even pending. and yes It has a filter. I drove today and it Really only dies with abrupt throttle close-age, probably due to the lack of a BOV and the fact that that turbo has antisurge ports (which would throw air into the back of the MAF, I think If I move it farther away from the turbo inlet I can get it to not die...

 

Either that or you could just bite the bullet and put it post-turbo. You would need at least a couple feet of tubing for the backwards air to equalize flow... and even then I doubt you could resist having it die 100% of the time. Been there done that, and I finally ended up putting the MAF post-turbo because I had to pump the gas pedal after almost every time I let off the gas. You should hook up a smart scanner with the engine off on ACC and see how smooth the TP goes up in relation to how far your foot goes down... as that is what triggers open loop.
And you've been in pedal to the floor boost?

 

yeah I've floored it . It accel's super fast even off boost. I'll try that TP thing, good idea. I may need to adjust my throttle cable. WOT AFR is like 12:1 or so. It does seem to be doing much better with the MAF pre-turbo, but youre saying post turbo works for you? Mind sending me a pick of you MAF setup? Also, yours never wants to die after boost the way you have it?

 

12 is not that bad for 4-5 psi. If you invest in meth injection, that will successfully be the "make up" fuel for that anyway. Post turbo MAF even though pre is better (in my opinion) will for sure get rid of your dying issue. Our MAFs weren't meant to see boost, so naturally pre turbo driving will be more consistent... but post turbo is ok. At least it won't die.

 

That's what I've heard too, pre is better, but I'll set mine back up post and see. I'm also gonna move the MAF farther away pre turbo and see if that does anything. Thanks.

 

Sweet dude! You're spraying intake and tb. That's cool. Is that special to your aem kit? I'd like to try this too. It must cool the impeller a bit too.....

 

I thought we covered this

When you close your TB suddenly and the air has no where to go, it flows back over your MAF and gets measured twice. The MAF is telling the ECU that the engine is getting air but the TB is closed so its really not. ECU doesn't know any better and keeps adding fuel to the motor causing it to go way too rich and stalling. You have the MAF positioned poorly as it will measure ALL the charged air from your entire intake runner while my MAF is close to the TB and will only measure the charged air in that short run (it will still go way rich though).

You MAF is positioned very good if you had a BOV close to the turbo as it will make sure most of the air in the charged pipe is vented before it reaches the MAF, but it will have to be tuned/adjusted for best results.

The best thing to do is get a standalone and tune it with a MAP. The next best thing is get an AEM FIC, measure your MAF voltage right before you start to get into boost and cap it there. That way your ECU never sees the extra air flow. Then, start to adjust your ECU injector signals with your AEM FIC and tune your fuel tables using the built in AEM MAP sensor. Make sure the MAP is reading manifold pressure POST TB and when you close your TB and the intake manifold goes to vacuum, the AME FIC will make sure the fuel is adjusted accordingly.

 

I only have the stall issue when im post turbo with the MAF, with it pre turbo it only stalls at high speed. Also my AFR gauge reads the engine is going lean when Its stalling and then blanks out. Im assuming your maf is right before the 90 degree bend into the intake? Regardless of me being pre or post turbo I still stall, although it happens much more post turbo, I would say no bov may be contributing but I don't see other non BOV guys having this problem.

 

So it goes lean? Weird. Maybe your IAC not opening fast enough when you shut your throttle? I still think its the MAF; a tuner that can cap the voltage and allow MAP tuning should go a long way either way.

 

I had assumed the IAC thing before aswell, may clean it. But I agree the AEM will definitely go along way.

 

Mine was way dirty. Cleaning that thing goes a long way. And not running your PCV shit through your intake should keep it clean as well.