7mge questions

[sas'd7mge]

im about to swap a 7mge into my 86 toyota 4x4. im unsure what year the motor is and the wiring harness has been hacked up. :nono: is there any way to find out what year the motor is? i dont know the VIN on the car it came from is...would the number on the block help? im going to do a full rebuild on the motor and dont want to get the wrong kit. who should i go with for the rebuild kit? RPM any good? not looking to spend over $700 for the kit if i can help it, and im planning on going with a metal head gasket and arp studs. also, whats the difference between the 86.5-88 and 89-92 7mge? the motor i have has green plugs for the coil pack, and distributor, and my injectors are yellow. would i be safe to just buy a 'green plug' wiring harness? what is the difference between the 'yellow plug' and 'green plug' wiring harness?
sorry for all the random questions, but im new to the 7mge scene. thanks for any help!!!

 

[bmoss85]

The wiring harness' are different, 86.5-88 are yellow plug and 89-92 are grey plug. They have different cranks also but its not really a big deal. You should check out www.supracharged.com. I'm doing a 7mgte swap into a friends 86 4X4 right now.

 

[sas'd7mge]

my plugs are green though for the distributor and coil pack. or are you talking about the 3 plugs that plug in to the ecu? cause those are yellow.

 

[bmoss85]

yes, Im talking about the plugs near the ecu sorry for the misunderstanding.

 

[sas'd7mge]

ok cool, just so i have this straight, the plugs that go into thre ecu are either yellow or grey. i might have a found a wiring harness and were just trying to figure out if his is compatable with mine, so as long the 3 plugs on his are yellow im good to go? also, does that narrow down what year my motor is?

 

[sas'd7mge]

anyone?

 

[shaeff]

It doesn't matter if you use a pre '89 (yellow plugs) or '89+ harness (gray plugs) if you're swapping the motor into the pickup. Supracharged.com covers the wiring for both harnesses.

The only differences on the motor are a few connectors that changed between sensors. They're all one-wire sensors, and easy to either A) swap out the connector via de-pinning it, or cut/crimp the proper connector on, or the better option is to replace the sensor with the proper one so you don't have to cut anything.

Either way, it's very simple to work around. Either harness will work for you, providing that you have the proper ECU to mate to it. (gray plug ECU's and yellow plug ECU's are not interchangeable between harnesses. If you have an ECU already, just get a wiring harness that matches the plug color and you'll be good to go.

 

[sas'd7mge]

sweet, thanks alot for the info....still trying to wrap my head around the cut-off years and whatnot with the 7mge. i actually got a pm from another member on the board and he has a yellow harness for me and am picking it up next weekend. thanks for the help

 

[sas'd7mge]

One more question...what are the differences between the yellow plug and grey plug ecu's? I've read something about an internal or external altitude meter? And one being digital and one analog? Is that correct or are there more or different things. I did search, but couldn't find any solid answers

 

[shaeff]

It's mainly just a wiring change. One isn't better than the other, they're just different. The 86.5-88 (yellow plug) ECU's have an external HAC (High Altitude Compensation) sensor, while the '89+ have it internal to the ECU.

 

[sas'd7mge]

ok cool. thanks for the info...sorry for all the newb questions. how about a rebuild kit? not looking to spend over $600-700. what are a few companys i should look at for a complete kit?

 

[bmoss85]

you can pistons and rings off of ebay for around $100, you can even get a complete gaskets set for like $70. then you will just need bearings and such, but i wouldn't get any bearings until i had the crank looked at.

 

[sas'd7mge]

any company to look for....good or bad? ive also seen a water pump & timing belt kit for $70 or so. but again, i dont want to buy crap parts so is there a brand i should look for?
how are topline, mizumo and npr?