S-AFC and boost, but whatabout timing?
 

I have a 89 T2, cant decide what ecu-path to go....
If i have larger secondaries (720cc) and a S-AFC, plus set boost to say 10,5 psi, what will i have to do with timing? A computerupgrade normaly alter the timing as well, but the S-AFC only alters the A/F, correct?
So how raise boost safe?

I have upgraded hybrid turbo (T04B S-trim), stock IC, FD pump, Greddy 720cc´s sec and ported wastegate. Dont have FCD yet, dont even now if i will need it with my wastegate ported......
Cars not running for the moment, so it is hard to find out. Here in Sweden it is winter!

////The Swede guy

Um i would stay away from timing. First you really should use a dyno if you are going to tamper with that. Second, you should really get aN FCD or make sure that the AFC compensates for the lack of fuel above 10psi. ( that's when the Fuel cut kicks in for a 89-91) Fuel cut has nothing to do with you wastegate being ported. That's a boost spike issue. If you're looking for a chip, then you might want to consider a G- Force. I got one and it's great.

Hmmm........
 

Thanks for replaying. What do you mean stay away from timing? I mean, all the chips are lowering the timing during high boost, right?
So, if i dont do anything, would´nt i be closer to spiking?

I thought wastegate had to do with fuelcut since the boost will be lower.... but, if I set the boostcontroller to 10 psi, i guess that will be 10 psi, no matter what i´ve done to the WG?

The G-force is out of business and btw we have 98 octane premiun here in Europe so i cant use any US market ecuupgrades.


///Kelimutu

I don't think you need to worry about timming all that much. But you do with out a doubt need an FCD. To my knowledge the SAFC can not alter or control the fuel cut function of the ecu. Do you have the proper gauges?ie)real boost gauge, A/F.

I have.......
 

boost and EGT, and i now i need the FCD, i just havent bought it yet, since i did so much at the same time when i upgraded my turbo it is a little hard to know what i need to do next....

I did all this: Bigger turbo, ported WG, , Blitz SSBC, FD pump, 2,5" DP and Highflocat, and all gaskets and stuff OC........

Before that i´ve been running for 2,5 years with just intake and 3" MazdaSpeed catback, with stock cats, and even that felt like 30 bhp, so i did not "need" more until now....

Maybe i buy HKS F-CON used, or a new S-AFC, or Unichip the hole thing (piggyback that is very good, the only thing that is available here in Sweden for T2...)

Re: S-AFC and boost, but whatabout timing?
 

I am not real familure with the T04B S-Trim turbo, I have a stock turbo on mine at the moment. pushing right at 13psi. I hit full boost at 3500-3800 rpm. I would say that you don't have to mess with timing, but i would make sure depending on when you are hitting full boost, that you make sure that you have enough fuel. I started off with just 720's in the secondaries, and because of when i was hitting full boost, I was maxing out the primary injectors and getting dangerously lean. Once the secondaries came on at 4000rpm everything was cool. So i had to put in 720's in the primaries and tune them down and everything was great after that. just something to think about, 2 720 secondaries may not be enough fuel with an upgraded turbo and a stock ecu with an SAFC. I would also make sure that you have an upgraded fuel pump too.

You may get some boost creep even w/ ported waste gate. I ported mine huge and put in a new larger disc seal for it and still when it was cold out or above 5000 rpms in 5th it would creep up above normal 7psi. I only noticed this after doing the TID mod though, which really helps the turbo breathe at high rpms. Boost controler can only raise boost from what the wastegate is regulating it at, not lower!

Your boost controller regulates the amount of pressure in your System, by bleeding the exhaust gas out of the way of the turbine. Fuel cut is a computer controlled, action that reduces fuel to the rear rotor at 8psi for the 87-88TII and 10 psi for the 89-91 TII. The fuel cut defensor "TRICKS" the computer into thinking it's always running less boost than it really is. Hence the computer never thinks that it's running over 10 psi for your car. That is why you need the bigger injectors and the S-AFC. To get rid of fuel cut you could : #1 get haltech or similar system. #2 get a FCD and tune it with an AFC or similar system. or get an aftermarket chip with that feature removed. check www.uprd.com for G-force chip info. I believe that they bought them out.

ok, Timming is just as important as fuel. with higher boost levels timming SHOULD be lowered. however there are only 2 ways to do this. either a ecu chip like g-force, or a haltech. many people manage to not have problems by just running richer instead. that is just a band aid. if you're running over 12psi or so on a stock ecu you should retard your base timming by 2-3 degrees. however this will lower you power thoughout the whole rpm range, but give you the safty up top. once again a band aid to not having a chip or standalone.

if you port your wastegate and run at stock boost levels you will not need the FCD. you will probably want the 720's and afc to give more fuel for the bigger turbo. highly recommand getting someone who knows how to tune to do it for you.

if you want to run 10psi you'll need the fcd, timming should be fine at that boost level the way it is. just make sure the fuel is ok.