85 long block in 87 . how?

[next_level]

when using an 85 block in a 87 what is the procedure....are the crank/cam sensors the same? i know you need to tap a hole in the pan for a return line from the turbo...is that all...

 

[Jerryl]

Is your 85 block a 20 bolt block?
I blief that the 20 bolt block was introduced mid 85 but I am not sure.
If you have a 20 bolt block, the sensors, timing cover etc should fit on the block.

 

[Dwayne]

the block will fit..no problem...but 84/85's had a different crank sensor, I'm assuming that you are using an 86/87 wiring harness so you would have to change the sensor...cam sensor is the same.....also, the 84/85 blocks had a taller deck height so keep that in mind if and when you change headgaskets...good luck

 

[Jerryl]

...but 84/85's had a different crank sensor, I'm assuming that you are using an 86/87 wiring harness so you would have to change the sensor...

BigDaddy,
Learn something new each day!
Not to pirate this thread but ...... Guess I have 2 concerns – Physical installation and compatibility on the wiring/ECM side.

So, the 85 crank sensor does not physically fit on a IC block?
Thought the crank sensor would fit if you use the hot air “fly wheel”?

Is the 87 crank sensor interchangeable on the wiring side of the installation when installed on a hot air?

 

[next_level]

hell i need to know the same stuff as you just un the reverse order...


so as long as i swap the 87 crank sensor onto the 85 block ill be ok...im going to use all the others from the 87 i would just like to avoid any that require setting (ie. cam sensor, crank sensor) trying to make this as easy and fast as possible...

and tapping a hole into the pan is an acceptable way to run the return line?

 

[turbodave231]

The 86-87 sensor should bolt up just fine regardless of which oil pan and front cover are used.

For the turbo oil return: You can drill and tap the block into the valley just like the 86-87 engine, or you can run a return line to the pan, or you can run a return line over and around the cam sensor and dump the turbo return into the fuel pump block off plate (that's what I'm currently doing).

 

[next_level]

ok so other then the return line, and the crank sensor....all it should be is swap all the 87 parts onto the block and turn the key right?

any recommendation on a head gasket? i figure while it's not in the car might as well put new headgaskets on it, i'd like something a little more durable then the stock type, unless everyone thinks that will be addequate for say around 20-21psi (with proper fuel/octane/alchohol)

 

[turbodave231]

Yup,

Use a steel shim head gasket (that's what 84-85's where built with). Bolt the intake and accessory items on........ and go. The bottom end of the 84-85 motor is vitually identical and should handle the HP. The only real difference between the two engines are in the head bolts (not TTY), head gaskets and a slightly higher deck height piston.

DR

 

[Dwayne]

...if you get studs, be sure and order them for an 84/85 block. They are a different length than the later blocks. The 86/87 blocks have a recess of about 1/2" before the threads begin whereas the 84/85 blocks were tapped all the way to the deck.....if you are using a 6/7 harness then use the 6/7 crank sensor.....good luck

 

[next_level]

alright, thanks everyone for the info...i think i got everything i need....

till i break it or blow it up again.....


thanks again
brian

 

[Lee Thompson]

Crank sensor

Just to be clear on the crank sensor.
The aluminum bracket is the same and both sensors will fit into the bracket and setting is no different. The difference is the plug on the wiring harness. An 87 sensor will not mate to an 84-85 harness as the other way around.
Build it RIGHT and run 27 PSI.

 

[next_level]

alright, thanks, i have the 87 harness, and sensor so ill just put that on the 85 block....

and once i get the old motor out, that'll be the one built to run the fun boost levels....this one just has to get me to work.....faster then most people