I am about to get my car finally put together, and am getting ready to order injectors, but i have a few questions. I have heard mixed things that MAFT can only compinsate for certain size injectors. I plan on getting 720 denso's at least, but would like more to cover future mods.

I guess i just need to know if i need to socket and chip the ECU even though i have the complete MAFT set-up. I have a fully built motor with comp 200's, ferrea dual springs, 1mm + valves, EVOIII 16g, FMIC, etc.. I plan on running 20 - 22 psi. Looking for at least 400hp. Does this sound do-able on the stock chip, or do i need to chip it.

Also, if i donot need to chip the car, where is rev-limit, fuel cut, etc.. I was just thinking that all the nice valvetrain might nit be fun with a 6500 rev limit!

thanks for the help

I believe a AFC would take care of your problem. I think i read somewhere with the combination of AFC and MAF-T you can run larger injectors.

screw the maft. get the maftpro: www.maftpro.com

rowlex said:

screw the maft. get the maftpro: www.maftpro.com

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sounds like a great idea, but i already have the MAFT, and i haven't even used it. Besides, id rather the PRO be out for a little while.

Ive been reading more posts, and it seems like people seem to agree that 650's or so are the limit of the SAFC and the MAFT. And as i think about it, i believe i would get a more accurate A/F with the chip and then the MAFT. Can anybody confirm / deny this?

Yes, it is going to be much more difficult to tune 720cc and larger injectors without a programmed EPROM chip. The AFC and MAF-T both alter the airflow signal to change the amount of fuel the ECU delivers. With 720's, you are running approximately 38% larger injectors, which means you are probably going to end up telling the ECU it is seeing around 38% less airflow.

Unfortunately, timing and airflow are related. When you tell the car it is flowing less air, the ECU goes ahead and bumps up the timing advance. This means that more likely than not you are going to end up with a timing curve that is overly aggressive, which is going to make tuning very hard. If you get larger injectors than 720's, you are going to have to tell the ECU there is even less airflow, making the timing even more aggressive.

The EPROM chip will make a global adjustment inside the ECU, so it thinks that 720cc/min (or whatever you end up getting) is the stock injector size. The EPROM chip will also adjust for the different injector dead time of the 720's, which makes it easier to get the fuel trims in line. And, of course, the stock fuel cut will be gone, making it even easier to tune.


Chris

OK, so im going to chip it then. I kinda wish i had looked into this part more when i bought everything. Id probably gone standalone or somthing just because having the MAFT, Eprom, and Dataloger (i havent bought yet) i probably would have came out about the same.

The limit for MAF/MAFT will be 550cc. If you went with MAF/MAFT/SAFC then the limit will be 650cc injectors.

DGajre777 said:

The limit for MAF/MAFT will be 550cc. If you went with MAF/MAFT/SAFC then the limit will be 650cc injectors.

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How is it any different with or with out the AFC ... the AFC and the Translator does the same thing (talking about tricking the ECU into seeing less airflow)

The limit for MAF/MAFT will be 550cc. If you went with MAF/MAFT/SAFC then the limit will be 650cc injectors.

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Are we talking about "limit" as far as tunability based on the corresponding timing curve that results due to the airflow compensation that is made or just "limit" as far as the size of injector you can run? I run the MAFT v2 with 550cc injectors (chipped EPROM) and I can assure you that you can run much higher than 550cc injectors. How is tunability with larger injectors? That I couldn't say as it depends on how aggressive that timing curve gets. I remember pulling airflow to compensate for the 550cc injectors when I had just an AFC and the resulting timing curve was excellent. I haven't tuned with the MAFT recently so I cannot share my thoughts on it yet.

TurboChrged93 said:

How is it any different with or with out the AFC ... the AFC and the Translator does the same thing (talking about tricking the ECU into seeing less airflow)

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Yes it does the same thing, except that the MAFT only adjusts on idle, mid throttle and WOT after you set your base.

chris90gsx said:

Are we talking about "limit" as far as tunability based on the corresponding timing curve that results due to the airflow compensation that is made or just "limit" as far as the size of injector you can run? I run the MAFT v2 with 550cc injectors (chipped EPROM) and I can assure you that you can run much higher than 550cc injectors. How is tunability with larger injectors? That I couldn't say as it depends on how aggressive that timing curve gets. I remember pulling airflow to compensate for the 550cc injectors when I had just an AFC and the resulting timing curve was excellent. I haven't tuned with the MAFT recently so I cannot share my thoughts on it yet.

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My "limit" above meant the ability to tune correctly based on the injectors and the bare minimum (MAFT or MAFT+SAFC), not the limit of the size of injectors that you can run. I apologize if I caused any confusion.

I don't mean to Hyjack by any means but I've ran into the same concerns with my set up that I hope to have by the end of the year. So which takes precidence when you have a chip, maft and safc? When it's chipped what do you set the Maft to for injector settings?

I skimmed over the tuning guide for the maft last night. It shows the maft has the ability to handle 9xx cc injectors. I doubt it could do it correctly though. Since with injectors that large dead time becomes a factor.

cdale said:

I don't mean to Hyjack by any means but I've ran into the same concerns with my set up that I hope to have by the end of the year. So which takes precidence when you have a chip, maft and safc? When it's chipped what do you set the Maft to for injector settings?

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A chip is programmed for your new injectors, timing, air fuel ratio/etc is compensated for in the chip. You set the maft/safc to 0. You do however do your fine tuning with the maft or safc. You do not need both devices in combination with eachother (Maft & safc) they do the same exact thing.

rowlex said:

A chip is programmed for your new injectors, timing, air fuel ratio/etc is compensated for in the chip. You set the maft/safc to 0. You do however do your fine tuning with the maft or safc. You do not need both devices in combination with eachother (Maft & safc) they do the same exact thing.

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And if you are "un-chipped", you can tune with the MAFT and fine tune with the SAFC.

rowlex said:

I skimmed over the tuning guide for the maft last night. It shows the maft has the ability to handle 9xx cc injectors. I doubt it could do it correctly though. Since with injectors that large dead time becomes a factor.





A chip is programmed for your new injectors, timing, air fuel ratio/etc is compensated for in the chip. You set the maft/safc to 0. You do however do your fine tuning with the maft or safc. You do not need both devices in combination with eachother (Maft & safc) they do the same exact thing.

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Well I'm thinking of getting chipped and I have the Maft for my blow throw setup and going to get an SAFC for fine tuning.

cdale said:

Well I'm thinking of getting chipped and I have the Maft for my blow throw setup and going to get an SAFC for fine tuning.

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Don't waste your money. The combination of all those will end up being MORE then to just purchase dsmlink, if it's not more it's definently close. You will also need a logger if you dont have one already. And you will still have a hard time tuning the car.

I really don't understand the concept of using a MAFT + SAFC combo. They do the exact same thing. A MAFT can also do fine tuning.

Here is how I see it-
MAFT: 200$+
SAFCII: 180+
CHIP: 125$
Pocketlogger: 150$

now that total comes to 655$. Dsmlink is $545. So you will be paying more or the same for an inferior setup. I have a friend looking to sell his dsmlink. Let me know if you want me to hook you up with him.

rowlex said:

Don't waste your money. The combination of all those will end up being MORE then to just purchase dsmlink, if it's not more it's definently close. You will also need a logger if you dont have one already. And you will still have a hard time tuning the car.

I really don't understand the concept of using a MAFT + SAFC combo. They do the exact same thing. A MAFT can also do fine tuning.

Here is how I see it-
MAFT: 200$+
SAFCII: 180+
CHIP: 125$
Pocketlogger: 150$

now that total comes to 655$. Dsmlink is $545. So you will be paying more or the same for an inferior setup. I have a friend looking to sell his dsmlink. Let me know if you want me to hook you up with him.

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I would like to pick up DSMlink but I have the MAF and MAFT, and a logger I just want something to tune more closely. I will be installing a 6bolt by the end of the year with a Frankenstien 19c, but I don't plan on going to much bigger than that, although that's what I thought when I bought the car and now I'm addicted to boost. If you're friend really wants to sell it within the next month I'm very much interested. Have him PM me if it's really an option.

I'll let him know. Don't know why your going with a 19c, but another buddy of mine is trying to sell his 50 trim that put his car in the 11's. (asking 600 obo for it --might come with additional goodies i dunno) I can get you in touch with him as well if your interested.

rowlex said:

screw the maft. get the maftpro: www.maftpro.com

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i want (need) that setup.. since i cant use pockettlogger or dsm link or any ecu specif tool (my obd port is pinned to eurospecs and its differentm, also i cant override the stock immobiliser because mitsu refuses to give out infos on it-no you guys dont got it in your 4g63s)

so, hows the maftpro work.. can i use any gm AIT and 3bar mapsensors?(can get em cheap from work
)

so im thinking it has a maf adapter plug for the 2g maf and all,or does one have to wire it to the ecu?

and who has the MAFT pro and how do you like it?

im tuning with an AFC and Wideband right now.

edit: if i stick on any other ecu other than the one that came with the car)ie its vin matched to the cars vin and immobiliser and to the chip inside the ignition switch and to the chip inside the cars keys) the car wont start.. so getting an 95 ecu isnt an option uneless i build it out of a 95 eurospec car,and use its ecu, its ignition key,switch and immobiliser control unit)

would it be possible to socket my ecu fo a chip ? to use with larger injectors? my car started out as an 4g63 nt with 340 cc injectors..

so....is the car a 1G or 2G non-turbo (with turbo kit installed)? Your car info shows a 98 n/t. But in your post said it started out 4g63.

rowlex said:

so....is the car a 1G or 2G non-turbo (with turbo kit installed)? Your car info shows a 98 n/t. But in your post said it started out 4g63.

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the handful of dsms that made it over here were all 4g63 nt or turbos..1g and 2g.. no 420a engines and no 1.8l

the nts had 150hp and the turbos had 210 hp..

so basically i took a 4g63 nt, and turboed it (by buying stuff and piecing it together.. 1/2 stock 2g and 1/2 aftermarket)

there is no "4g63 to turbo conversion" option in the vehicle profiles so most people think its a turboed 420a ..which it is not ,and they think im crazy running 12psi on 9.5 compression..


yes i know,why not swap everything.. couldnt find a donor car..

so you see my situation? everything thats plug and play for you guys may not work for me

check my galerry for some pics

OK...well i am not incredibly knoweldgeable with this stuff but I know a little bit, maybe someone with more experience can chime in.

I know Mavisky has a lot of experience with turboing the 4g63, drop him a msg im sure he will help you out more then I can.

To answer some of your first questions, I dont think you will be able to chip your stock ECU, as the only first gens with the chipping abilities are in the 90-91's, and 95's.

The same concept applies to you that applies to 2G n/t's you need a SFMU or some type of adjustable fuel pressure regulator. I am fairly certain the 1G NT does not use a MAS type air counter so you may be unable to make use of the MAFT. (mainly because you dont have the wiring for it).

That I think is the extent of my knowledge sorry I couldnt be of more help. Their are some guides in the Tech Articles area for turboing the 420a which is just like turboing your car just on a different engine, you will need the same basic parts.