lexus afm and 550cc inj's

[ma67 lover]

So i have been reading on doing this on my 7mgte and what I have seen is that if you use the lexus afm you have to use 550cc injectors to match so that your ecu will take this in right and this can be run on a stock ecu no tuning required. thats pretty awesome but question is why? is there a power gain in this at stock psi? or is it just nice for future tune-ability? oh and happy 4th of july everyone!

[discoelk]

I'm pretty sure there are no gains with this mod on stock boost. Also, as I understand it, you need an SAFC or your car is going to run rich as hell.

[Wolfgang]

From what I remember on this, with 550's and the matching AFM, you dont get more power stock, but you do get the ability to boost higher before hitting fuel cut.. I could be wrong though. I thought the lexus AFM let you run the larger injectors with out ecu issues/needing a AFC..

[ma67 lover]

IF-you dont want to spend the money on an AFC, and retain stock ECU, you have to retain 440/stock afm, or 55o/lexus afm combos, as stock computer cant adjust outside of its programmed learning curve. Whatever you do, you will need a good wideband to "tune" with. Unless everything else was given to you free, no reason at all not to have one already....

according to carfreak it does work with stock ecu

[discoelk]

Good to hear. I must've been thinking of something else. I'm pretty sure theres tons of threads on this subject on supramania.

[ma67 lover]

humm shall check that out.....

[4SFED]

the afm for the Lexus v8 is larger diameter but otherwise a Karman vortex unit like the 7mgte stock afm so it's a cheap easy way to get some better breathing into your 7mgte and keep it relatively stock. Increasing injector size from 440 to 550 correspondingly increases the fuel delivery

[CarFreek]

It does two things. First, you increase fuel and air delivery by 25%, so even at stock boost, you will see a power increase, figure 15-20% with stock ECUs "tuning" ability. Second, the larger diameter means a given volume of air moves slower past sensor, allowing more air to flow for a given sensor output. This means you can run higher boost levels before fuel cut sets in. On stock AFM, Fuel cut happened at 12 psi with my car. I still havent seen it at 18 psi with same turbo. Heres a very old link.http://www.suprasonic.org/public_htm...exusnotes.html

[ma67 lover]

yeah im really wanting to do this little upgrade just still lookin for some good injectors. Im hoping by now everyone knows about venoms so thats out, I have seen alot of deschworks (sp) injectors around but to be honest i havent heard much about them, im probably just going to spend the money and get some rc ones soon cause they are reputable company.

[83restomod]

denso or RC injectors. done