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302 or 351W

I have purchased a 70 mustang with a 351w out of a ford torino. The car starts up and moves but was back firing out the carb as well as falling on its face after a short distance. The car smells like its running rich I was thinking that the car was loading up and that the timing was off. After messing with the car some more I found that the spark plug fire order was off. So I changed the order to what a 351W was calling for and yes I went counter clockwise on the cap. Although that didnt do a thing for me. after I changed it it would not start at all... So I thought Maybe I have a 302. So I tryed the fire order for the 302 and It fires over. although it hasnt back fired since out the carb, it still smells like its running rich or possibly running to much fuel. I investigated further and looked up the part number on the Intake manifold and it came up as 351 exclusively.... so my next question would be WTF! how does a 351 fire on a 302 fireing order, and if it is a 302 why or how did someone put a 351 intake manifold on it? I am about to loose my mind..

As of now with the 302 fireing order, I place the car in gear and it basically loads up... looses power

Any suggestions?

Reply to
justineverything
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A 351 intake will not fit a 302. Assuming it is a 351W, the firing order should be 1-3-7-2-6-5-4-8 - I assume you understand how Ford numbers the cylinders (1 2 3 4 front to rear on passenger's side, 5 6

7 8 front to rear on driver's side).
Reply to
C. E. White

Dont know about the 302/351 distinction, but a friend did a valve job on a Bronco 351 . When he put it back together he did the firing order as labeled on the intake. It backfired, etc. A mobile mechanic came over and said the firing order on the intake was incorrect. He redid the wires and it ran fine.

I always wondered about that.

G
Reply to
Gene Wagenbreth

Ford changed the firing order of the 302 to the 351W firing order. Really all they did was change the camshaft and it only changed the order between two cylinders. I've been told they did it because over the years a lot of engines were ruined because of crossfiring between the plug wiring that would cause preignition on the firing order of the old 302s. Can't say for sure that it is true though.

The OP has me puzzled unless somebody actually put an older 302 camshaft into a 351.

Reply to
Kruse

There's no real differance between a 302 cam and a 351 cam - except the firing order. Other than that, they are interchangable. In some years, it's the same. In other years, it's not. Whoever swapped the motor may have installed a differant cam for some reason. You have to try and figure out the proper firing order. Here's how to do it:

Remove the spark plugs, and the valve covers. Place a marker (blue masking tape) on each intake valve rocker arm. Place the engine at TDC, with cylinder #1on the compression stroke. Use a socket and ratchet to turn the engine over two full rotations. As the engine turns over, watch the intake rocker arms. As they start to open, write down the number That's your firing order.

Who ever had the car before you, may have been using the incorrect firing order. You can make the car run, but not well. They may have compensated by putting in the wrong jets, or placing the base timing at some wierd setting. Once you set the correct timing order, then you can check everything else.

-------- .boB

2006 FXDI hot rod 2008 Mustang Coupe 2001 Dodge Dakota QC 5.9/4x4/3.92 1966 Mustang Coupe - Daily Driver 1965 FFR Cobra - 427W EFI, Damn Fast.
Reply to
.boB

Reply to
scott

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