I don't understand why but,

[mcammarn]

I've got basic performance upgrades on my 7m but I'm still hitting fu cut. Why is this?
I thought with bpu, you should be fine without tuning.
I've got spearco I/c, hard pipe upper kit, fpr, 320lph fuel pump? 560 inj, Lexus afm., full 3in back, and 57trim ct26.
I've got a safc2 just havnt installed it yet along with a wideband.
But like I said this is just bpu so I shouldn't need to tune it right?

 

[jake8790]

Boost level? Checked for boost leaks?

 

[mcammarn]

Mbc is seat around 10 I wanna say. I didn't turn the dial at all. There are no boost leaks

 

[jake8790]

It shouldn't hit fuel cut until 18-19 psi with that setup. Are you sure it's fuel cut? Does the CEL come on when it happens?

 

[Supra mn]

Have you messed with the Lex Afm adjustment screw at all?
I have the same setup as you, but with a 60-1. Have yet to hit fuel cut, running 18 psi.
Just tuned it by adjusting fuel pressure and that adjustment screw on the afm.

I think there's an old thread by Reg Riemer explaining the whole 550/lex mod, and how far you should back that screw out. Just search on google.

 

[mcammarn]

Yea the cel hits when it happens.
I'll check out my afm

 

[mcammarn]

So I been reading up on the Lexus adj screw, if mine is stock, then all I need to do is fit a longer screw?

 

[seoul4korea]

why not just clamp down the voltage and be done with it lol FCD or Emange blue can do it.

 

[Supra mn]

You don't have to buy a new screw, just drill out the aluminum cap on the AFM and dremel a slot on the existing screw. Then just grab a flathead and adjust it.

 

[mcammarn]

I don't get it?

 

[Supra mn]

Here's a very detailed thread about how the lex/550 upgrade works. Interesting, but basically all you need to know is that it works..
http://suprasonic.org/lexusriemer/lexusnotes.html

Anyways, take a drill bit and drill this out. Don't worry about drilling too far, as you're just drilling out the cap. You'll feel it actually drill through.


After you drill through the cap, get something in there to pry it out. Once you get the cap removed, get out your dremel and grind a slot into the now exposed screw. It should look like this:


And anything else, here's a full install guide of the lex afm and all supporting mods:
http://www.mk3supra.org/topic/82-guide-installing-lexus-afm-550s-and-afpr/

 

[Nick M]

I think there's an old thread by Reg Riemer explaining the whole 550/lex mod, and how far you should back that screw out. Just search on google.

A better idea is go to a dyno with a four gas analyzer and see what happens going in and out in small increments. You don't need a five gas, but it is fine if they do. And they do have one, or they could not tell you A/F.

 

[7M4EVR]

There is a screw already in your afm underneath that little metal cap looking thing but u have to drill out to get to it. I used the biggest drill bit i could find and drilled in the middle. You wont damage the screw when u drill through because u will feel the bit get through the cap before it hits the screw. Theres about a half inch gap inbetween the two. You dont need to dremel as my screw already had an indentation for a flathead. Now, all that being said, you should do none of it lol. Leave it where it is and get a proper way to tune, safc, maft, etc. adjusting that screw and the fuel pressure in conjunction with a wideband is a very limited way of tuning. I couldnt get fuel cut to raise much at all or really any change in my AFR's no matter how much i played with it.

Sorry just noticed i was beat to the punch on this post (didnt refresh the page after coming back to it from putting the kids to bed.) Nicks post is a good suggestion.

 

[Poodles]

I've got basic performance upgrades on my 7m but I'm still hitting fu cut. Why is this?
I thought with bpu, you should be fine without tuning.
I've got spearco I/c, hard pipe upper kit, fpr, 320lph fuel pump? 560 inj, Lexus afm., full 3in back, and 57trim ct26.
I've got a safc2 just havnt installed it yet along with a wideband.
But like I said this is just bpu so I shouldn't need to tune it right?

Bigger turbo flows more air at lower PSI, but it's still too low. Still sounds like a boost leak...

why not just clamp down the voltage and be done with it lol FCD or Emange blue can do it.

Not unless he wants to build a grenade.