i've got a 1jz w/ a small t4(58mm) turbo, 440cc injectors and a 2j map sensor w/ a stock ecu.. has anyone ran a similar setup like this w/out leaning out?
is this a safe setup to hit 17psi in?
- Thread starter slidingsidewayz
- Start date
I wouldn't risk it if I were you. Do the necessary upgrades to be sure you can do it. What happens if you overboost... you'd be kicking yourself.
C
cnewingham
Guest
wideband will be your best friend in this case. if you are already at the single stage then you should already have a w/b installed
go to the dyno and for usually 50-80$ you can find out HP Torque and A/F.. not a bad deal if you ask me..
^^ agree... don't risk it get it tuned, spending a few buck is better than buying a another engine
if i'm mistaken i heard with a 2jz map sensor it's suppose to up the fuel cut from 1bar to 16-17psi, is this correct?? because i've tried boosting 15 psi and it start backfiring kind of like a boost cut..
lack of fuel? but i've got 440s on w/ the stock ecu.. correct me if i'm wrong but doesn't the stock ecu always run towards the rich side?
The different MAP will cause your A/F to change as well. The 25% increase (2.0 bar abs -> 2.5 bar abs) in MAP reading means it will be set for about 462.5cc injectors, assuming the relationship is linear.
You could also be running too rich at that PSI and experiencing spark blowout. I ran the same setup for a while and was way rich up top.
Bottom line: get it tuned.
You could also be running too rich at that PSI and experiencing spark blowout. I ran the same setup for a while and was way rich up top.
Bottom line: get it tuned.
ohh i c.. i was assuming that it was running way too rich up top so i'm going to hook up my wibeband and safc2 when i get home from work later. but what's a spark blowout exactly?mobes said:
Basically with increased cylinder pressures or excessively rich fuel mixture, the resistance between the spark plug electrodes increases to the point that it doesn't fire. Aftermarket ignitions like the HKS Twin-Power are usually the fix for high boost motors. However, the cause can be as simple as running too rich or too wide of a gap.slidingsidewayz said:
i just found out that im still hitting fuel cut around 14-15psi.. so i don't think it was a spark blowout.
can anyone confirm if the 2jz map sensor/440cc injectors will illiminate the stock fuel cut from 1bar to 16-17psi?
can anyone confirm if the 2jz map sensor/440cc injectors will illiminate the stock fuel cut from 1bar to 16-17psi?
ic.. you're the first person to ever say that about the 2j map sensor.. i've been hearing people say that it raises the fuet cut up to 16-17psi.. thanks for your input bro..tissimo said:
Fuelcut is not based only on pressure. Let go of the pressure idea and start thinking in air mass.
Fuelcut is based on a certain air mass, which is pressure AND air temp. Change one of the two and the air mass changes.
For example: you could boost the stock twins to 18psi and not hit fuel cut with a 2jz map sensor, but slap on a big single and you could hit fuel cut at say 13psi, just because a big single will move a bigger mass of air at a much lower air temp.
So, it's not at a fixed number of psi where fuelcut occurs, but it's a fixed amount of air mass.
Fuelcut is based on a certain air mass, which is pressure AND air temp. Change one of the two and the air mass changes.
For example: you could boost the stock twins to 18psi and not hit fuel cut with a 2jz map sensor, but slap on a big single and you could hit fuel cut at say 13psi, just because a big single will move a bigger mass of air at a much lower air temp.
So, it's not at a fixed number of psi where fuelcut occurs, but it's a fixed amount of air mass.
slidingsidewayz said:
the stock 1jzgte ecu is mapped for the stock 370cc injectors..... by dropping in the 440cc injectors it throws the factory fuel map off.... the ecu can compensate to an extent but it wont be a 100% recalibration, thus you may have some lean and rich spots.