Lexus AFM question?

[ddmcse]

you remove the wiring (black box)off the lexus afm and put the supra's afm block box onto it .
you'll need to get the 25% larger diameter afm inside the accordin hose that connects to the turbo.
--sounds easy

you really shouldn't add a lexus afm without knowing exactly what you are doing .

you should have an air/fuel gauge installed
you should have larger injectors installed

[rnoswal]

Wait a minute, I was always under the assumption that it is a plug and play item. I have never heard of anyone having to swap out the black box from one to the other. I am pretty sure they both have the same plugs and then yes the upgrade for the injectors.

Anyone outhere that has this mod? Besides shoving the larger afm into the smaller bellows, that should be if for that.

Russ

[djalkyd]

that is what i am saying i did. i just plugged it in and it works great. better than stock even.

i took my a/f today on the smog dyno at school and the stock injectors are fine at 5psi boost, which i am running right now.

so for the record, the 94 LS400 afm with the lexus sensor does work with stock injectors and low boost. no need to swap sensors in my book just use the one that comes on it.

[ddmcse]

it made sense to me to use the stock box .it probably doesn't matter it just eliminates wondering if they are different if you have a problem .
i really wouldn't recommend using the lexus afm with stock injectors .
i'm sure it will work but the question is for how long and if you don't have an a/f meter and you don't get on a school smog dyno every day how will you know if you've slipped into lean .
or at how many lbs does the mixture get too leaned
i guess once you've poured some blood, sweat and tears on the block you have more respect for the car

[rnoswal]

Well, I think he has respect for his car just as you do. I also think the the Lexus afm does of course allow for more boost but I also think that up to the limits that the original let the car boost, is also a safe limit for the larger Lexus afm. Sure it will allow more air, but 10lbs boost is still the same now matter how big the afm is. But because it will allow much more boost than stock you have to limit your boost to a safe level, but bigger injectors and fuel pump are still the way to go to be safe I realize.


Correct me if I am wrong though.

Russ

[ddmcse]

i didn't mean he has no respect for his car .
i mean that once you have to taken the sucker (engine) completely apart and gone through the agony and cost of rebuilding , you are left way more cautious and less tempted to beat the crap out of it .

[ddmcse]

extreme heat is the enemy
lean = heat

[lethalwithasupra]

Nice site, ddmcse. And the car sounds awesome

Sooo ... afm + injectors from a Lexus ls400 v8 ? Any designation about the engine ... told it's " the 5.0L, " but others say they use a MAP sensor ...

[djalkyd]

Originally Posted by ddmcse

i didn't mean he has no respect for his car .
i mean that once you have to taken the sucker (engine) completely apart and gone through the agony and cost of rebuilding , you are left way more cautious and less tempted to beat the crap out of it .

i totally agree with you but what i am saying is that i lowered my boost to make up for the amount of air going in. stock boost is 8psi and i went down to 5psi. i ran on the dyno with a wide band under full load in all gears and the leanest it got was 14.9 to 1, when 14.7 to 1 is most desirable.

this week i am adding the injectors and the adjustable fpr with the s-afc so i can crank the boost up.

but i totally agree on the blood sweat and tears. i have been building my other car for years and have built many other peoples cars in the past so i know what you mean when you grenade or melt down internals.

i also thought you would have to use the stock sensor but i found out that the car responds better with the lexus sensor. for some reason unknown to me but it works.