Yes, ^^^, you have the wrong size rotors or the wrong calipers, it would not come from the factory that way.
Not sure on the rear speakers never looked at that on an '87
Yes, it could be timing.
The computer controls the spark advance and retard while engine is running, so to set base timing you need to disable computer control.
SPOUT(spark out) wire comes from the computer to the distributor(TFI module)
There will be a connector on this wire that you can unplug to disable computer control.
You can Google: SPOUT connector
But it is usually easy to find, it is near the distributor, follow wires coming out of TFI module, usually has Yellow wires and a Black or Grey plastic connector the slides out to disconnect the wires.
With SPOUT disconnected, set timing at 10deg BTDC
Plug in SPOUT and go for a test drive.
You can set base timing where YOU think it runs best, 8deg to 12deg BTDC, or whatever you like.
You 2.9l also uses a Speed Density fuel system, so you will have a MAP(manifold absolute pressure) Sensor that gives the computer engine load information.
MAP sensor will be on the firewall passenger side towards the center, usually behind wiring harness, it isn't big maybe 2"x2".
It will have an electrical connector and a Vacuum hose attached.
Vacuum hose runs directly to the intake manifold.
Unplug electrical connector and make sure it is clean and dry
Unhook vacuum hose, at both ends, and pull it out, make sure it is air tight and the ends are not hard or brittle.
MAP sensors rarely fail and a hesitation would be the least of your problems if it had failed, but a small air leak or dirty connector could cause issues.
A working Thermostat has nothing to do with overheating, simply doesn't work that way.
Thermostat sets the MINIMUM engine temp, so unless it is broken it can't cause over heating, i.e. MAX temp.
Correct thermostat for your engine would be a 192degF or 195degF.
This MINIMUM temp gives better MPG and cleaner oil, warmer temp burns off oil contaminants, i.e. water/moisture and fuel/blow-by.
S.A.E.(the oil lab guys) did a study years ago, and that is when auto makers switched thermostats to 190+ degF.
The 180degF was the choice before that knowledge was available.
If your engine was running too warm, above 1/2 on gauge, then it wasn't the thermostat unless it was broken.
Could be rad getting older and having more blocked tubes, water pump impellers could be worn down.
These would show up in warmer weather when more cooling is needed.
Computers sets idle matching engine temp, 1,100 cold, 700 warm(manual), 800(automatic).
Computer has its own 2 wire coolant temp Sensor(ECT), dash board gauge uses a 1 wire temp Sender, they are usually located near each other.
Cold engine needs a higher idle, just like choke cam did on a carb engine.
As engine warms up, computer lowers the idle based on that temp(from the ECT sensor)
Computer use the IAC(idle air control) Valve to change the RPMs for idle.
This valve can get dirty and stick, it is on the upper intake near the throttle plate, it is an electric stepper motor operating a valve that lets more or less air into the intake, a controlled vacuum leak, lol.
Remove it and clean it.
Unhook battery for at least 5 minutes while doing this, this will cause computer to reboot when started again and then relearn IAC Valve settings, it can take a day or two of driving.
Last edited by RonD; 02-14-2015 at 12:10 PM.