I have a 1JZ in my mk3, currently on the stock twins, only think done is front mount, 3 inch all the way back, and other little things. I would like to go small single and reach 350 whp. I would like to stay on stock injectors, stock ecu, and was thinking of getting something like a GT35 or a BW s257 or something around those sizes.
So 10 psi on the twins is not going to be the same as 10 psi on a single, there will be more air coming in at 10 psi on the single at 10 psi vs the small twins. Because the 1jz are MAP, it goes by the pressure, so here's my question:
1. Does the ecu only use the map as its only way to determine how much fuel to give?
2. Because there will be more air coming in at 10 psi on the single, will the engine lean out a bit more? My guess is because it's still sensing only 10 psi on the single, it will give out the same amount of fuel as if it was 10 psi on the stock twins, but because 10 psi on the single will be getting more air, the engine will lean out because it's still giving the same amount of fuel, so it's not really compensating.
3. Should I get a fuel cut defender, my boost cut is at around 13 psi and I'm sure I'd need to be at 13 psi or so to reach 350whp.
4. How do you think the car will run if I do this?
I've read people saying they've ran setups like what i am going for as long as i stay under boost cut. Most people get an AFC but i would like to avoid that route if possible. Also, I have a AEM wideband and boost gauge, since I know people will tell me to get that first.