2nd gen 7mgte motors

[mk3_7m]

Hey guys im trying to find out more info on the 2nd gen 7mgte motors compared to the 1st gen 7mgte motors. Now as far as im aware from information from "Google" and other supra forums everything is almost the same but the crank is diff on the 1st gen 7m that uses a 6m crank which revs 400 to 600 rpm higher then the 2nd gen 7m and the 2nd gen 7m motor is 2hp higher.

At the moment i have a 1st gen motor with the 7mgte 87-88 ecu yellow plugs & loom , motor is basically getting old and rings are worn. before i buy this 7mgte 92 2nd gen motor (jdm imprted) can i just use my existing loom and ecu or would the 7mgte 87-88 ecu would have negative affect to the 2nd gen 7mgte motor

thanks guys

regards,

 

[NewWestSupras]

Aside from small differences in the head & block casting, "more" counterbalanced crank, motor mounts, slightly different sensor config, and tb, it's basically the same engine. As long as you use the sensors, tb, and water neck from the old one you should be good to go. Jdm has some different smog stuff, too. gl.

 

[IJ.]

Block differences are far from "small"

 

[NewWestSupras]

I'll defer to you on that Ian, I meant more like nothing fundamentally changed with config. I know they are "beefier". But all the parts fit still, is what I was referring to.

 

[IJ.]

Ahhh got ya!

Yes the layout is identical but they added a huge amount of Iron into them they're +2mm just about everywhere.

 

[super.secret.supra.club]

wait, i thought the 7m is more counter balanced allowing it to rev higher more then the 6m crank while the 6m crank is able to produce more torque per rotation.

 

[NewWestSupras]

I believe the extra counterweights caused it to redline 500 rpm slower stock, but be "smoother" ... of course you could have the best of both worlds if you shaved the 7m crank like Ian! I don't think too many 7M owners have the resources & savvy he does, though.

 

[IJ.]

7M is heavier so they limited it lower in the ECU it's happy to rev higher if you can get around the limiter.

 

[gaboonviper85]

wait, i thought the 7m is more counter balanced allowing it to rev higher more then the 6m crank while the 6m crank is able to produce more torque per rotation.

Naaa...6m crank 7m's redline at 6500....the 6m crank is much lighter than the 7m...but the 7m is fully counter balanced giving it much more potential for high rpms...the 6m would rattle the piss out the motor at high rpms...if two motors were stock never to be modded then I'd chose the 6m....but for high rpm builds the 7m crank will be much better at reduceing vibrations.

 

[IJ.]

Over 8000 they both felt much the same

 

[gaboonviper85]

I believe the extra counterweights caused it to redline 500 rpm slower stock, but be "smoother" ... of course you could have the best of both worlds if you shaved the 7m crank like Ian! I don't think too many 7M owners have the resources & savvy he does, though.

As badass as that old shit IJ is, knife edgeing a crank is not a product of his personal brilliance...it's pretty common!

 

[IJ.]

Ahhh but it's knowing where and how much material you can remove before you affect the inherent balance of an I-6 crank that takes some brilliance
(not mine but the computer programs)

 

[gaboonviper85]

Over 8000 they both felt much the same

yeah I'm sure...it's like running off balance parts in the cnc lathe....once you get above a certain rpm you don't feel the vibration but it's still there...off balance is off balance

 

[IJ.]

Yep up to 7>7500 the 6M was quite a bit harsher and both my cranks had identical prep and balance and were run within 2 weeks of each other.

 

[mk3_7m]

Thanks guys for the help much appreciated

 

[paradox616]

i noticed on my 6m crank block it has no oil squirters...where as my 7m block did, both 7mgte's....

intresting...

the 6m cranked block i have is no 1173 built.... where as my 7m crank is 123,343 or something.. maybe it was a early block before they decided to do any squirters????