help me ID my motor

[svtpower]

Ok, so I bought an 87 SD LX 5.0 with 3.73s an offroad H and flowmasters. It is gutless for low end torque and backfires sometimes at under 2,000 rpms under load but pulls pretty darn good once I get moving. Runs great on the highway but stalls out sometimes when coming up to a light. No codes though.

I went to put on a set of underdrive pulleys last night because I had them laying around from my last 5.0 and the water pump pulley 4 holes wont line up with the 4 holes on the pump shaft. It's like it's not a Mustang water pump or something.

So then I started wondering if maybe it's not a Mustang engine or something. It has the normal upper intake with the 5.0 HO plate on top but maybe somebody just slapped that on a different motor.

The casting on the lower intake is RF-E6SE-9K461-D3A which if I am not mistaken means it's from an 86 Tbird?! Which would be non-HO. Which would mean a different firing order too I think. Anyone else have input on this?

This was all last night at like 2am and I didnt have the pulleys back on it to give it a try moving the plug wires.

The alternator also doesnt have the usual spikey fins on the front, instead it has a plastic disk that kind of looks like a vented brake rotor instead, I forgot to get the part number off it, but it's definately a ford part.

Anything else I can look at to help me know for sure what kind of motor this is?

 

[Mikey1968]

http://www.wrljet.com/fordv8/

 

[jrichker]

This doesn’t prove that the block is a HO block. Some trucks evidently use a HO firing order
with a low lift cam. However, it will definitely prove that a block can’t be HO because the firing order is wrong.

Remove the #1 & #3 spark plugs. Put your finger in #1 spark plug hole. Crank the engine over until you feel compression on #1 cylinder. Slowly turn the engine until the TDC mark and the timing pointer line up. Mark TDC on the balancer with chalk or paint. Put your finger in #3 spark plug hole and crank the engine 90 degrees. You should feel pressure trying to blow past your finger. If you do not feel pressure, repeat the process again. If you feel pressure, it is a HO engine.

No pressure the second time, remove spark plug #5. Put your finger in #1 spark plug hole. Crank the engine over until you feel compression on #1 cylinder. Put your finger in #5 spark plug hole and crank the engine 90 degrees. If you feel pressure now, the engine is not a HO model, no matter what it says on the engine.

Using a small carpenter or machinist square to mark the harmonic balancer off into 90 degree sections may be helpful here.

A 15/16 deep socket & breaker bar or ratchet may be used to turn the engine.

The HO firing order is 1-3-7-2-6-5-4-8.
Non HO firing order is 1-5-4-2-6-3-7-8

 

[v8only]

is it an auto or stick???? auto car's blow chunks in stock form, and are gutless wonders.