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Not ur jizz, not ur bizz
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Discussion Starter #1
tho I hear alot of people talk about what they READ or HEARD from others that putting a lex afm on a stock rich pig fuckin mk3 turbo is bad news.

however, i havent really heard from anyone that has first handedly suffered the consequence of running a lex afm with stock fuel.

anybody encounter first hand experience theyd like to share?
 

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1/2 Na-T Project
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chevyeater-on-sf said:
I didn't but a friend melted some pistons with a Lex and 440s.

Go for it, let us know how you make out.
How much boost was he running? Did he have a wideband and egt gauge? There are many factors that would go into play when someone melts some pistons. The lex and 440s are only two of those factors. I demand more info. :D
 

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Not ur jizz, not ur bizz
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Discussion Starter #5
chevyeater-on-sf said:
I didn't but a friend melted some pistons with a Lex and 440s.

Go for it, let us know how you make out.
you know, ive owned 3 supras...my first two have never EVER EVER ran near as rich as the one i have now.

everything works in the car perfectly...just runs so incredibly rich as if there was a walbro fuel pump in there with the 12v mod.
after a couple days worth of normal driving..my rear bumper, taillights etc. has darkened from the rich exhaust gasses. You can smell the fuel once u get to a stop light.

the only thing i havent done is check the tank to see if there is an aftermarket fuel pump..but like i said, this car runs rich like its had something added to it.

on my first 2 supras..ran normal, got great gas milage, no richness, no fumes, no black smoke at [email protected] boost, no soot or whatever on my entire rear of my car. So, no i wouldnt put a lex on it, it would have never been an option without fuel modifications..it ran great.

on my current one..the lex is becoming more and more of an option to see how much change there is.

i tried it today..car ran great..ran a bit rich on boost...ran normal under boost and normal driving..and went to normal lean when i was at idle or in deceleration.

heard no pinging..car ran fine..gas milage increased, car didnt backfire all the time. SO i just dont know. wish i had someone with a wideband i can use for a day *shrugs*

i just wanted to hear personal testamonials on the whole topic.
 

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wastegate hose is pulled
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JT87NA said:
How much boost was he running? Did he have a wideband and egt gauge? There are many factors that would go into play when someone melts some pistons. The lex and 440s are only two of those factors. I demand more info. :D
Since I didn't do it, I don't know all the specifics, sorry. A Lex and 440s will let you melt the pistons though, unlike a stock AFM and 440s (assuming everything else is good). If you think you are smart enough to handle it safely, don't let anyone stop you. But, if you need to ask....
 

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Turbonetics..faggot asses
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As long as you put an ADJ fuel regulator on to compensate for the fuel the LEX will pull out you shouldn't have any probs running stock injectors
 
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TO START IF YOU ARE GOING TO USE THE LEX AFM UPGRADE YOU SHOULD DO SOME REAL DYNO TUNING TO MAKE SURE EVERYTHING IS IN THE CORRECT OPERATING RANGE. THE PROBLEM WITH THE LEX AFM AND 440CC INJECTORS IS THE LEX AFM IS CALIBRATED TO RUN A V8 SO THE SCALE IT OPERATES AT IS HIGHER THAN A 440 CC INJECTOR CAN HANDLE NOT TO MENTION THE ENGINE IS UNDER BOOST WICH REQUIRES MORE FUEL AT A CERTAIN POINT. ALSO TOYOTA ECU'S , AND MASS AIR FLOW SYSTEMS HAVE A LITTLE BIT OF ROOM TO ALLOW MODS SUCH AS INCREASED VOLUMETRIC EFFENCY THAT WHY THEY TEND TO RUN ON THE RICH SIDE AND HAVE SOMEWHAT LARGE INJECTORS STOCK . SO WHEN YOU INCREASE THE SIZE OF THE MAFS AND YOU dont CHANGE THE INJECTOR SIZE TO CORRESPOND WITH THE SIGNAL BEING SENT TO THE ECU BY THE MAF THE SYSTEM NOW HAS AN IMBALANCE ITS REPORTING MORE AIR THAN THE STOCK FUEL SYSTEM CAN DELEIVER SO YOU RUN LEAN AND GUES WHAT THATS WHEN THINGS START TO MELT
 

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Turbonetics..faggot asses
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ADJ fuel pressure regulator
 

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90Legend said:
Last post hurt my eyes.

You can't know if your running rich or lean without a WB.

Period.

Dan

Edit- the one before Fried Rice
Agreed.

I had tons of black smoke out my exhaust usually, and soot on the rear bumper (damn white cars). As well as the smell of fuel. Indication of running rich.

Upon removal of the exhaust/turbo there was white residue around the flange. Indication of running lean.
 
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THATS WHY YOU NEED TO DYNO TUNE TO SEE WHERE YOUR AT AFTER THE UPGRADE. AND A PRESSUR REGULATOR ALONE IS NOT GONNA DO IT
 

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Moderator, l337 M0d3r4t0r
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my buddy bobby just blew his engine from this...he had 440's, lex, walbro, stock fuel pressure and made piston 6 break... well not only break but crumble.... Who knows what went on there... I told him he was running lean for sure especially since he was running like 16 PSI on a upgraded stock turbo.
 

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Not ur jizz, not ur bizz
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Discussion Starter #18
ZaZZn said:
my buddy bobby just blew his engine from this...he had 440's, lex, walbro, stock fuel pressure and made piston 6 break... well not only break but crumble.... Who knows what went on there... I told him he was running lean for sure especially since he was running like 16 PSI on a upgraded stock turbo.
stock FPR, upgraded tock turbo @ 16psi, lex and 440's seem like a recipe for disaster indeed.

i guess what im shooting for it for those who get teh lex on stock fuel and keep the boost under 12psi on a stock turbo on a car that does run exceedingly rich in stock form.

i mean ive been asking this question around...heard both sides of the story "i heard is blows motors like a mothafucka"

then i hear "bro, we did that on my friends car and strapped a wideband on the dyno and it was fine, just keep it under 14psi."

though i hear both sides...im just curious as to how many have actual personal experience from the specific scenario provided. that being full exhaust, stock fuel, lex, 12 psi, stock turbo, car ran super duper rich before hand.
 
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when you dyno tune for real or at a good dyno facility there should be a wideband o2 to use that will tell every thing the motor is doing. or if tou really want to tune it to the max put a egt probe on each cyl and tune each cyl but that would require stnd alone (motec)
 
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