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*I see you*
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Discussion Starter #1
I know they're good.. everyone has one it seems. I was wondering how much they help out? Ok, I have int. and exh...not a lot. If i were to get an AFC and have it tuned would the car run noticeably better? Or would I be better off waiting till I get bigger injectrs and whatnot? What, if anything, would I nothice different in my car?
 

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You would but it wouldnt be much. You'll notice a lot more difference with some bigger injectors, a lexus afm and maybe a better fuel pump. I know I did, I had everything but put the safc on first without supporting fuel and didn't notice to much of a difference.
 

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when this baby hits 88mph
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the more mods you have the more it will help to get everything running correctly.
there was a magazine (import tuner or turbo) that dyno'd w/ int and exh then tuned w/ an afc. they picked up ~15rwhp.

edit: it was import tuner and was a 91t w/ a blitz intake and blitz exh
 

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if you mostly leaned it out, it will help gas mileage where it was leaned. I have done some research and have found people claiming from 20 rwhp to 45 rwhp (dynod) from tuning alone. These had stuff like intake, full exhaust, stock injectors and CT, the usual...

How much can fuel cut be eaked out to if you tune to 11.8 - 12? anyone know?
 

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I wouldn't do an AFC until you have done the basic mods along with a fuel system and a larger turbo. The only reason you would need a bigger fuel system is for a bigger turbo anyway.

If you only put a larger fuel system on and not a turbo, you are just tuning it back to what it would be with a stock fuel system, so why not do a turbo?

I didn't use an AFC until I had done just about everything I wanted to do. At 18psi on pump before the tune, I was making only 340rwhp or so. By the time the tuning was done, I was almost 420rwhp. I gained almost 80rwhp from just tuning. It makes a huge difference when you have that much on the car. I don't think it would make much of a difference at all in your car and definitely not worth the money it would cost to have to pay someone to tune it only to have to turn around and re-tune it later when more stuff goes on.
 

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Madd Tyte JDM yo ®
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you dont realize how much you need an SAFC untill you already have it

it can benefit people with as few mods as Intake filter, DP and exhaust... trust me, ive seen it done. Ideal Supra and Psifactor are 2 people who's cars ive tuned personally.

once you open up the 7MGTE and 1JZGTE, the conservative Toyota tuning really shows. the 1JZ hits 10:1 AFR's and richer after 5400rpm. the 7MGTE hits 10:1 AFR's and richer after 4500rpm.

if you had an SAFC, you could remove ~15% fuel to bring the AFR's to a sane 12.3-12.5:1... and this would also put off fuel cut a little bit more and allow you to run a few more psi of boost, via shimming or what have you.

when you have one and get it tuned, youll be much happier with it. the car DOES feel different between "BPU" untuned and "BPU" tuned. the car feels alot stronger, alot more crisp and the exhaust note is definitly more well defined. you can feel and hear the difference before and after tuning.

besides, Everyone is going to need one at some point, generally speaking. might as well get it now
 

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*I see you*
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Discussion Starter #9
well, the safc i could do fairly soon. as far as bigger turbo and fuel.. that's a ways down the road. I was also readin on the map ecu. I din't get enough info yet, so I won't be getting an afc just yet. If I like the map ecu after reading more I may wait and go that route.
 

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Madd Tyte JDM yo ®
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map ecu is too much for the fwe things it does do. plus its tedious to tune. my friend has it on his MKIV and it sucks to tune with it. im sure someone will chime in and defend it. but IMO, its not worth the money. all that money and its STILL running on the stock ECU and maps. all its doing is allowing you to run a MAP sensor and convert it into Karman... youre STILL scaling AFM input which is going to alter your timing curves. if you scale it down too much, your timing is giong to be more aggressive cuz the ECU thinks there is less boost... and this will just cause headaches with knock and such.

the SAFC is alot more User friendly, cheaper and does the same job. the MAP ecu requires that you input fuel tables for ever 1.2psi in manifold pressure change. this means you could be sitting at a lap top for 5 minutes making ONE single adjustment... and if you are only running 14psi and only insert fuel corrections up to 15psi and then have a boost spike, youll have NO fuel correction over 15psi and youll melt your pistons. its a VERY real problem with the MAP ecu. when you could have youre whole car tuned with the SAFC, corrected and adjusted several times.

the map ecu is a glorified VPC thats harder to use and has more pitfalls... in the end, youre still scaling AFM signal... save $600 and multiple headaches and possible blown engines and get the SAFC.
 

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With only intake, exhaust and fuel pump upgrade I was able to make 240 rwhp with a few shims behind the waste gate and the EVC and SAFC II turned off. At 14 psi (EVC and SAFC II turned on) I made 302 rwhp. These were back to back runs.
To me, the SAFC II gives you about the same horsepower on warmer days as you feel on colder days. The only problem I've noticed is that now on colder days, it leans out. I guess I'll have to have it tuned twice a year (warm temp and cold temp) to get good performance year round.
Anyone know of an easy way to increase fuel across all 12 setting by making just one adjustment?
 

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DAMN u a big one lady
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I'm in the same boat as a few ppl right now. I just sent out the turbo last week for a rebuild (60 trim) and I figured I'd get some fuel mods as well. 550's, AFPR, Bigger pump, some sort of AFC, WB o2, and a few other things. When ever you play around with fuel, it's always a good idea to get some electronics to back it up. Supras run mad rich to begin with, so whenever you're going to be dropping more fuel into her, you'll need something to lean it out.
 

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Matthew 6:33
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Is the SAFC II all that is needed with the Walbro, Lexus AFM, and injectors to tune for smooth idle and ensure richness up top? I was told the Emanage would be required. Is the Emanage overkill? Goal is 350 RWHP as a daily driver.
 

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You wouldn't need the e-manage for that...

I plan on trying to tune completely with my afpr/lex afm before even turning on my s-afc to see what type of a/f's I can get with that..

Shit, I bet I could reach 340 no problem if I could pull 12.6-12.8 a/fs.
 

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when this baby hits 88mph
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Disced said:
You wouldn't need the e-manage for that...

I plan on trying to tune completely with my afpr/lex afm before even turning on my s-afc to see what type of a/f's I can get with that..

Shit, I bet I could reach 340 no problem if I could pull 12.6-12.8 a/fs.
yikes! id say not. that is a lot more lean than i would run and on top of that i played around w/ a/f and found anything leaner than 12.2 it would start to drop power due to the engine starting to pull timing, and this was on race gas.

as far as better mpg no, thats really idependant of an afc. most of your driving is during closed loop operation which the 02 will take care of a/f. you can adjust the afc all day long and under closed loop the 02 will fight against it. perhaps during open loop you will get better mpg since it wont be dumping as much fuel, but if you spend a lot of time wot it will suck anyway.

im w/ flubyu on this one, it can really help at the early stages since they run so rich from the factory from 4.5k up. of course as was said once you get fuel upgrades it will help even more. but you cant deny the power increase from a tuned car, no matter the mods.

dave
 

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*I see you*
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Discussion Starter #16 (Edited)
dbsupra said:
i played around w/ a/f and found anything leaner than 12.2 it would start to drop power due to the engine starting to pull timing, and this was on race gas.
Is that tuning on a dyno? Isn't a little different than on the street with real loads on the motor? Does the SAFC only move fuel cut when lex afm and 550's are there?
 

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Madd Tyte JDM yo ®
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dyno tuning is really close to street tuning. the only difference is that all the variables are constant.

rather than having a colder intercooler the faster you go, the intercooler stays one temperature as the airflow over it stays the same. the dyno places a load on the engine as it is, not very different than just driving.

since you wont be trying to correct for constantly changing variables like on street tuning, you will be able to compensate for all the "consistant" variables while on the dyno. the nice thing about the stock ECU is that it uses various sensors to trim the fuel tables as it senses changing conditions, like altitude and temperatures and such. on a dyno, the temps and altitude and baromter and such all stay the same... driving all up and down the free way can yeild different conditions which you will be trying to tune out when adjusting your AFC.
 
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