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TheFlyer100
07-08-2008, 09:19 PM
I have 87 351 ( i believe) and like a bone head i pulled off all of the wires and did not trace them back. I have found that there are 2 firing orders for this RH engine.
IF i miss wire the engine, will it cause immeadiate damage?

I tried to give a tune up by new plugs and wire, cap & button b/c it ran "rough" above 3500RPMs and was only pushing 39 mph. After installing new gear, now it will not run above 2000 RPMs. I check the timing b/c it was 20deg BTDC and now runs worse.

Can any one help me straighten out this mess? Firing Order and Correct timing.

JimN
07-08-2008, 10:20 PM
Look on the intake manifold for a series of numbers. That should be your firing order. Otherwise, try the other order. You didn't say if you got it to TDC on #1, so do that first. remember, the crank turns twice for every revolution of the cam. Also, remember that you have 1-2-3-4 on one bank anad 5-6-7-8 on the other with #1 being the farthest forward. Does it backfire? Verify the rotation direction of the rotor, too.

6°-10°BTDC is your timing. If you have a sticker on one valve cover, it should have your tune up specs on it.

kah68
07-09-2008, 09:02 AM
Look on the intake manifold for a series of numbers. That should be your firing order. Otherwise, try the other order. You didn't say if you got it to TDC on #1, so do that first. remember, the crank turns twice for every revolution of the cam. Also, remember that you have 1-2-3-4 on one bank anad 5-6-7-8 on the other with #1 being the farthest forward. Does it backfire? Verify the rotation direction of the rotor, too.

6-10BTDC is your timing. If you have a sticker on one valve cover, it should have your tune up specs on it.

At what RPM should 6-10 degrees be seen?

JimN
07-09-2008, 11:00 AM
I have always seen Fords timed at idle, so about 650-700RPM. GM injected motors are timed at 1000RPM.

denverd1
07-09-2008, 12:55 PM
Isn't there just one firing order for 351?

TMCNo1
07-09-2008, 01:00 PM
Isn't there just one firing order for 351?

That may be covered in some of these threads, http://www.google.com/cse?cx=partner-pub-1573311577903577%3Aculy35-3701&ie=ISO-8859-1&q=351+firing+order&sa=Search

denverd1
07-09-2008, 01:26 PM
That may be covered in some of these threads, http://www.google.com/cse?cx=partner-pub-1573311577903577%3Aculy35-3701&ie=ISO-8859-1&q=351+firing+order&sa=Search

uh.... yea, i guess it would.

At any rate, my '86 351W is 1-3-7-2-6-5-4-8. IIRC 302s used two different firing orders, depending on the year. peace.