lex afm and hks super dragger 3in exhaust?
- Thread starter cjmkIII
- Start date
lexus afm tricks your car to run richer so if you get 550's you can push the fuel for them, this allows you to run higher boost without hitting fuel cut. But no you don't need them for your car to run right. But it may be running a bit rich as it sits without them.
well you can pick up a pair of used 550's for fairly cheap, i think their might be a trick to the resistor wire you need to change or add/on. I'm not too sure as I';m not a 7m guy just what I;ve read. but this way you can push a lot more then 10 lbs on your car. but your turbo/intercooler will be your next wall after 13-14lbs.
Beals;1930225 said:
Bigger AFM means you'll run lean. Lean = motor go KABOOM.
A bit of an over statement yes but it is very possible.
Pick up a set of 550cc injectors (expect to pay around $300 used) AND a new fuel pump.
^ plus one to that. More air and less fuel means LEAN!!! Not rich. If you want to put the that Lexus Maf on you will need. A safc, afrp, bigger intectors, afr gauge, and tuning. If you just slap that Lexus Maf on well let's say its not a good idea.
my bad, good thing he corrected me lol. but he means is a air/fuel pressure regulator to check if your running lean/rich with it. and a SAFCII is a tool to tune your car or piggyback. but it's definately a fair bit of work not for the feint of heart especially with the piggyback. I mean I replaced the turbos and swapped out my injectors but I have an aftermarket ecu and even my electronic boost controller was a pain in the ass and I'm an electrician. not to mention a front mount intercooler can be a nightmare if the piping isn't perfect trying to plumb it without any instructions.
The Lexus AFM/550 injector combo is a simple way to get more fuel.
The added fuel is matched with the increased air flow allowing the ECU to read as if everything was stock.
And the added fuel allows you to run around 25% more boost before hitting fuel cut.
You can then run a SAFC to further fine tune the air/fuel mixture but it is not required.
Now I'm curious.
If you were using a SAFC you could (in theory) run 550cc injectors without using the Lexus AFM, right?
How much adjustment does it have and how big of an injector could you run on the stock AFM?
But that is a topic for another thread.
The added fuel is matched with the increased air flow allowing the ECU to read as if everything was stock.
And the added fuel allows you to run around 25% more boost before hitting fuel cut.
You can then run a SAFC to further fine tune the air/fuel mixture but it is not required.
Now I'm curious.
If you were using a SAFC you could (in theory) run 550cc injectors without using the Lexus AFM, right?
How much adjustment does it have and how big of an injector could you run on the stock AFM?
But that is a topic for another thread.
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cjmkIII;1930283 said:
Lol no worries. Everyone has to start somewhere.
To start you will want:
550cc injectors -stay away from venom injectors
Lexus AFM (Air Flow Meter) out of a sc400 or similar -you really only need the housing as the sensor is interchangable
and a Walbro 255 Fuel Pump
Also, make sure to search the site. A LOT of this information is already out there, you just have to find it.
Good luck!
Alphabet soup translation:
SAFC: Apexi additional fuel controller. A piggyback computer for adjusting the AFM signal. (Yes, if you have this, you don't really need the Lexus AFM to run larger injectors, since it will alter the AFM signal by itself.) I don't think that this is needed in order to run the Lexus/550 mod myself, certainly not while you're still running a stock turbo. The whole point of the Lexus/550 mod in the first place it to raise fuel cut without the need for piggyback computers.
AFPR: Adjustable Fuel Pressure Regulator. Allows you to alter your mixture a little by changing base fuel pressure. Typical installs also eliminate the "J" tube restriction, thus allowing for higher fuel pressures at elevated boost. This is a good idea, but again, I don't think that this is needed in the range where the stock turbo operates.
AFR Gauge: Air/Fuel Ratio gauge. This pretty much has to be a wideband in order to be useful. Running lean is your enemy, which is why a wideband is recommended by most everyone. Myself, I don't think that you need one until you have something with which to tune the car. With the 550cc injectors, and Lexus AFM, you're running everything as if it were stock. The stock Toyota tuning is very conservative, and quite safe at anything that the stock turbo is going to push without grenading itself.
MAF: Mass Air Flow. Take as a synonym with AFM (Air Flow Meter). There are technical differences between the two, but in the case of these cars, we're talking about the same thing.
For the purposes of my opinions, the stock turbo isn't helping things past about 13, MAYBE 14 PSI positive manifold pressure. At this level of boost, just make sure that you have good 550cc injectors (reputable new buy and/or cleaned and flow tested injectors) and that your fuel pump is healthy. This will get you past the stock fuel cut restrictions, and I believe that this can be done without the need for additional fuel control or monitoring safely. Naturally, you will be increasing the stresses on the engine, so if there are any below-the-surface issues with your 20+ year old 7M-GTE, expect them to come to light in short order.
As soon as you are dealing with an upgraded turbo, things start to change. Increased boost levels now will require better fuel supply, so that means fuel pump and fuel pressure regulator. Actually, even the same 13PSI at the manifold might require this, since it's likely that there will actually be more air at the same pressure. I still maintain that the wideband AFR is something that should come with a method of actually tuning the AFRs, and the Lexus AFM itself isn't it.
Making power combined with ignorance is a short trip to having a boat anchor under your hood. For now, the list that AbsoluteSpeed gave you is a good place to start, and will probably get you another 50 ponies to the ground on cheap boost control.
SAFC: Apexi additional fuel controller. A piggyback computer for adjusting the AFM signal. (Yes, if you have this, you don't really need the Lexus AFM to run larger injectors, since it will alter the AFM signal by itself.) I don't think that this is needed in order to run the Lexus/550 mod myself, certainly not while you're still running a stock turbo. The whole point of the Lexus/550 mod in the first place it to raise fuel cut without the need for piggyback computers.
AFPR: Adjustable Fuel Pressure Regulator. Allows you to alter your mixture a little by changing base fuel pressure. Typical installs also eliminate the "J" tube restriction, thus allowing for higher fuel pressures at elevated boost. This is a good idea, but again, I don't think that this is needed in the range where the stock turbo operates.
AFR Gauge: Air/Fuel Ratio gauge. This pretty much has to be a wideband in order to be useful. Running lean is your enemy, which is why a wideband is recommended by most everyone. Myself, I don't think that you need one until you have something with which to tune the car. With the 550cc injectors, and Lexus AFM, you're running everything as if it were stock. The stock Toyota tuning is very conservative, and quite safe at anything that the stock turbo is going to push without grenading itself.
MAF: Mass Air Flow. Take as a synonym with AFM (Air Flow Meter). There are technical differences between the two, but in the case of these cars, we're talking about the same thing.
For the purposes of my opinions, the stock turbo isn't helping things past about 13, MAYBE 14 PSI positive manifold pressure. At this level of boost, just make sure that you have good 550cc injectors (reputable new buy and/or cleaned and flow tested injectors) and that your fuel pump is healthy. This will get you past the stock fuel cut restrictions, and I believe that this can be done without the need for additional fuel control or monitoring safely. Naturally, you will be increasing the stresses on the engine, so if there are any below-the-surface issues with your 20+ year old 7M-GTE, expect them to come to light in short order.
As soon as you are dealing with an upgraded turbo, things start to change. Increased boost levels now will require better fuel supply, so that means fuel pump and fuel pressure regulator. Actually, even the same 13PSI at the manifold might require this, since it's likely that there will actually be more air at the same pressure. I still maintain that the wideband AFR is something that should come with a method of actually tuning the AFRs, and the Lexus AFM itself isn't it.
Making power combined with ignorance is a short trip to having a boat anchor under your hood. For now, the list that AbsoluteSpeed gave you is a good place to start, and will probably get you another 50 ponies to the ground on cheap boost control.
Beals;1930225 said:
Yet more BS in the tech section from people who have NFI what they're talking about. Might want to read the rules.
wow thanks for all the knowledge guys very helpful.! ill let you know when the mods are all done how she runs. i bought the car with the lex afm allready installed. didnt know how much it entails when it comes to the upgrade but i cant wait till its all done! to all have a good one and drive smart!