1JZ Discussion

[Brown Duckz]

Just a few questions that have actually never been specifically answered for me.

[1]What amount of boost is safe for the stock twins. [pump gas]
[2]What's the deal with the boost creep?
[3]What kind of power can one expect with a full exhaust and increased boost?

[got_trd]

Just a few questions that have actually never been specifically answered for me.

[1]What amount of boost is safe for the stock twins. [pump gas]
[2]What's the deal with the boost creep?
[3]What kind of power can one expect with a full exhaust and increased boost?


[1]What amount of boost is safe for the stock twins. [pump gas]
- I boost between 1.07-1.10 bar daily on pump
[2]What's the deal with the boost creep?
- Never really experienced that
[3]What kind of power can one expect with a full exhaust and increased boost?
-1000hp to the wheels :thumbup:

[Arizona]

Ive havent noticed any common boost creep issues with 1jzs on forums. SO i wouldnt worry about because no one else is. With I/E and upping the boost people have netted over 300whp. With other BPU+++ stuff ie Intercooler hard Pipes BOV and some tuning 350 and possibly 400 with a good tune and upping the boost.
Just go single :D

[Brown Duckz]

Just go single :DI'm doing everything in stages. I want the motor to be completely stock when it first fires, that way I can rule out aftermarket being any issue. Then I'm going to go BPU.. which really only consist of a full exhaust and boost controller, I might throw a front-mount in the mix on stock twins, don't know yet. I'll go single when it's time...... I'm waiting around for a good manifold to come out. ;)

[got_trd]

Ive havent noticed any common boost creep issues with 1jzs on forums. SO i wouldnt worry about because no one else is. With I/E and upping the boost people have netted over 300whp. With other BPU+++ stuff ie Intercooler hard Pipes BOV and some tuning 350 and possibly 400 with a good tune and upping the boost.
Just go single :D

you cant really go over about 370hp on stock injectors....

[Bean]

yeah, the JDM 2jz 440s and MKIV (JDM or USDM) 1.3 bar map sensor will fix that quickly :)

[Brown Duckz]

yeah, the JDM 2jz 440s and MKIV (JDM or USDM) 1.3 bar map sensor will fix that quickly :)You say 1.3 bar map, does the map automatically change the boost level?

[Last5Spd]

you cant really go over about 370hp on stock injectors....


wat other injectors should we be running?

[Bean]

You say 1.3 bar map, does the map automatically change the boost level?

no, its just a sensor? it just senses the pressure... the map-based 1jz uses a 1bar map sensor, and the map-based 2jz (the USDM motor has this sensor still even tho it uses a MAF) is 1.3bar

the increase in size with the 1.3 map sensor coincides with the increase in size of the injectors (going to the JDM 440s or USDM 550s -- which both bolt in-- 550s need a resistor pack)... a la LS400 AFM for the 2jz-GE guys

[Brown Duckz]

no, its just a sensor? it just senses the pressure... the map-based 1jz uses a 1bar map sensor, and the map-based 2jz (the USDM motor has this sensor still even tho it uses a MAF) is 1.3bar

the increase in size with the 1.3 map sensor coincides with the increase in size of the injectors (going to the JDM 440s or USDM 550s -- which both bolt in-- 550s need a resistor pack)... a la LS400 AFM for the 2jz-GE guysThanks for clearing that up. I'm guessing the 440s will take on all the power the stock twins will make. Is a walbro neccessary to start with? Also do you think SAFC2 will be sufficient in adding fuel on the stock twins?

[Bean]

Thanks for clearing that up. I'm guessing the 440s will take on all the power the stock twins will make. Is a walbro neccessary to start with? Also do you think SAFC2 will be sufficient in adding fuel on the stock twins?

I would assume it isnt, the stock fuel pump can flow pretty decent BUT I'd run a GS341, stock SupraTT pump, or a SoarerTT pump anyways. Its not expensive, easy to install (can do it before you swap the motor), and its good insurance :)

Yeah SAFC2 will be fine for fuel tuning.