Not a Lexus, but I run a Lex AFM/550cc/S-AFC combo on my MK3 Supra. The car makes a little over 400 to the wheels and is just street tuned (by me). Under full boost, ~20psi, the car is running AFRs in the high 11-low 12 range. Ive been running this combo for a couple years now with no engine damage to report.

I think you'll be fine as long as you dont push it. Tune it a little rich and you'll be ok.

 

Well they are ****in idiots because it doesnt have anything to do with timing. All it does it trick your ECU into adding (or subtracting) fuel

 

You're wrong. Yes the AFC does trick the ecu into adding or subtracting fuel but a side effect is timing change.

When you pull fuel, the ecu automatically advances timing, and vise-versa.

 

Its what I am running. Not bad for now, but I plan on getting an AEM

 

yeah, WAY indirectly, Its not gonna add 70 degrees of advance or retard... youre talking about simple timing changes that the ECU does CONSTANTLY. Its not like you are gonna pull or add so much timing that youll break anything... NOT TO MENTION the 2jz isnt an interference engine. The way he makes it sound is that it adjusts timing. Anything your ECU does, even if tricked, is still safe for the car. If your car is capable of adding or subtracting the fuel, than the timing associated with it is fine as well. you should be fine. Itd be way easier to screw something up if you are on standalone, as you can change a lot more. Ive never personally heard of anyone blowing their engine because of an safc2 messing up their timing, ive built and boosted many cars with that setup... personal cars as well as customer cars. Thats just preposterous.

 

Oh of course it's not going to go as far as changing timing a ridiculous amount. I run an AFC in my car and no doubt it's okay. Timing change is definitely not a big side effect but I was just saying that that side effect is there, even if it's just a little one.

The only thing I would worry about is maxing out the AFC with plus or minus 50. Other than that you should never have any problems with it.

 

Thats what I thought you meant, just making sure.

 

So long as you stay with reasonable sized injectors and keep your AFC adjustments on the low side of things, the timing advance isn't a huge huge deal, however, it is still there... What most people end up doing and not even realizing they are doing it is compensating for the additional timing by adding even more fuel to prevent detonation...

Its not that it can't be done, its just a detriment to the AFC... if you go with a piggy back or standalone that can adjust timing independently, the engine will be a lot happier and healthier...

For those that don't understand the correlation, I'll give you a quick rundown...

When you install larger injectors, an AFC fools the computer in to thinking that there is less air going into the engine, so that it opens those injectors for a shorter period of time... Larger injectors, shorter open time... The reality of it is that you are going for more air for more power, but you don't want to go over the stock map or the stock injectors capabilities... The AFC and larger injectors combined allows this quite well... The side effect is that the ECU sees that not as much air is going in to the engine, because the amount of air going in to the engine (should be) proportionate to the load on the engine, the ecu advances timing thinking it has less load... timing advance can be a nasty cause of detonation, especially if you are running close on your AFR's...

just a related FYI... those resistor boxes that are sold on ebay that claim horsepower gains and such are usually just a potentiometer or a set resistor set that is wired in the intake air temp range... they fool the ecu by lowering the voltage on the intake air temp sensor, which has a side effect of raising advancing timing as well... just some food for thought to retard timing along the same route, if someone could wire up a voltage multiplier and do the opposite???

 

I know what youre saying, and im not saying youre wrong, but Im not saying Im wrong either. For simplicity sake, he isnt gonna do any harm to his car by running it. Stay sane and stay withing your cars capabilities to avoid breaking things, (within reason) if you start maxing any part on your car out... its time to upgrade. The people that run maxed out electronics or parts are the ones that break things.

 

okay great help everyone thanks. well ill have sometime to install the safc this week as im not driving my car, came home one night and decided to do some pulls, was doing good at around 9-12.5 psi until my final pull and the compressor side of my turbo blew off and destroyed my compressor wheel, so now i have to rebuild my turbo for the third time and buy a new compressor wheel and a proper snap ring to hold it.

oh man i get some ****ty luck....
but great on the timing issue, the safc is just temporary until i get a power fc. but should do the trick

 

sounds like you need a different turbo...

 

well it was burning alot of oil but i guess its also my fault for not fixing the oil drain issues. i have new bearings, housing, its basically brand new besides the ****ty oil and wheel issues

 

don't forget it will need to be balanced as well...

 

ya i had it balanced and rebuilt before i blew it. the balancing is only 50 bucks at the shop by my house