What's the difference between an N374 and N370 ECU?

 

Not much. I believe it's the Jspec version of the n370 and the difference between the two is only emissions related. You can swap afm and boost sensor between n37x ecu.

 

N370 ECU's came in 1989 TII's only. Most 89 TII won't even run right without that ECU. The N374's came in 1990- 1991's. They are interchangeable though.

 

You my friend are incorrect! All U.S. S5 t2 came with n370 ecu. N374 is japan,other countrys. The n374 will not for with U.S harness. Secondary injectors will not fire. Some people have had luck chipping them.
Thanks Robert

 

then what about a N380? My friend Tenchi has one in his 89 J-spec?

 

So If I install a JDM T2 Into a 90 NA T2 with the NA harness, would I use a N370 or N374 ECU. I notice that when you buy a JDM engine, it generally comes with an ECU.

 

n370 that will work fine for th e t2