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Discussion Starter #1
What is the difference in the JDM spec motor and the US spec motor? Injectors , turbos?? please explain

thanks
 
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Discussion Starter #3
so what would it take to make a JAP spec US spec.. Just the bigger injectors??
 
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Discussion Starter #4
SupaDupa said:
so what would it take to make a JAP spec US spec.. Just the bigger injectors??
If you wanted to make it exactly like a US spec one I think you would need to change out the turbos, injectors, and cam. And the jap spec injectors have a different impedence, so you would have to use a resitor pak for that. Not sure what other differences might exist.
 

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Sorry to change subjects a little bit but,

I have a US Supra with a J-spec motor and a t-78. Stock fuel by the way and the jap-spec fuel rail.
I didn't put the stuff in, I just bought it that way.

Is there anything I need to know as caution or any gains by using J-spc motor? I am keeping boost to 10psi.

Can I easily swap the J-spec fuel rail with the U.S. spec or just the injectors?
 

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Yeah, you should use the USDM injectors and rail for sure on the T78 at least... actually you should just upgrade the fuel system further than that anyway. A T78 isn't even trying at 10#s. In fact the waste gate shouldn't even let go until 14 or so... How are you keeping the boost that low?
 
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Discussion Starter #9
Probably just a different wastegate spring.
 
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Discussion Starter #10
so i found out the cam is differnt and the injectors... anything else?
 
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Discussion Starter #11
Usual R Suspex said:
Sorry to change subjects a little bit but,

I have a US Supra with a J-spec motor and a t-78. Stock fuel by the way and the jap-spec fuel rail.
I didn't put the stuff in, I just bought it that way.

Is there anything I need to know as caution or any gains by using J-spc motor? I am keeping boost to 10psi.

Can I easily swap the J-spec fuel rail with the U.S. spec or just the injectors?
I am pretty sure the rail is the same for both cars just the injectors are different.
 
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