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The machine shop put a 351 Windsor cam in my 289 engine. Do I need to change the firing order of my engine to that of a 351? If so, what is the firing order? Thanks!
 

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If the W cam has the traditional W firing order, the correct order is 1 3 7 2 6 5 4 8

You can verify it by cranking the engine and watching the order in which the
valve sets come up on compression.
 

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While we are on this subject, I have a question also.

What, if any, advantage is there to using a 351W cam in a 302 to change the firing order? I have read of people doing this to specifically avoid #7 and #8 cylinder firing consecutively in the 302 firing order. Is this an issue of any importance? Is there any other reason for using the W cam in a 302?
 
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I discovered by accident that my engine (289) has a 351 w cam in it as well. Yes you defenitely have to change the firing order...the car will run like it's on 2 cylinders otherwise! Pop, bang, shutter...is about all you'll hear. Greater lift and duration, so more power in that 289. I've heard from some friends that putting a 351 cam in a 289 is a cheap effective way to get some more power without having a big crazy cam! That about exhausts my knowledge, and as you can see...it's not much!
Dave
 

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I asked a similar question a while back. Read it here with responses.

The guys changing just to avoid cylinder 7 & 8 crossfire are kidding themselves. With the "new" firing order, 5 & 6 now fire in sequence, so you have the same problem.

The real reason for changing is that under the "old" firing order, 1 & 5 fired in sequence, placing a lot of torsional stress on the crank, which were transmitted over the entire length. With the "new" sequence, 4 & 8 fire in sequence instead, which reduces the torsional stress, since they are located closer to the output point.

Clear as mud? /forums/images/icons/wink.gif
 

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Great! Thanks for the link.

The theories all seem sound. It's something to consider for sure.

Another decision to be made for my 331. Just what I needed.*G*
 

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Good point on the crossfire, but I gave it some thought. The 7-8 combo is nearly twice as far away from the distributor. The longer wires needed to reach would contribute to the crossfire moreso than the 5-6 which are right up front. I would agree though that it was probably a seconary effect, and that the engineers were concentrating on the torsional loading effects.
 

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I gave your thoughts some thought too /forums/images/icons/crazy.gif, and in many Ford installations, #5 & #8 would be nearly identical in length (as would #6 & #7)...since they go thru a clip in the center of the valvecover, then either forward or rearward.

Now, if you came off the distributor, along the front of the head, then rearward, there would definitely be a length difference.
 

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Good point. I forgot that's how the wires are routed from the factory.
 

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What, if any, advantage is there to using a 351W cam in a 302 to change the firing order? I have read of people doing this to specifically avoid #7 and #8 cylinder firing consecutively in the 302 firing order. Is this an issue of any importance? Is there any other reason for using the W cam in a 302?

IME, six of one, half dozen of another...I always ran traditional FO's on the 289/302 engines in the race car and never had a bit of trouble with stock cranks, even with outputs of over 400hp. Conversely, the current W is running its stock FO with equal results. Theories abound, but, at least in my experience racing at my level, it's not a big deal. 2HP/ci+? Possibly...

Contact Alex Denysenko (M&M moderator and SS racer) and ask him about it...he'll give you some straight advice if it already isn't in the archives on the M&M boards...
 

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Pat,
Kind of what I thought too. Much ado about not too much.

If the torsional thing was impacted by one or the other, it would seem less of an effect with the 289/302 FO. Less distance.

Anyway, kind of a moot point for my application I would think. The steady high rpms of a race car would probably make it noticeable at some point. Like maybe the next generation. *G*

I did drop Alex a quick note just for giggles. I saw a fleeting mention in the archives. But nothing about torsional stress. More of a cross-fire type thread. By the way, his Moneymaker certainly launches impressively. No?

It's always fun to learn something new and get other's views and thoughts.

Later.
 

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I figure one can always teach this old dog new tricks but I just never thought things like this were holding me back performance-wise or reliability-wise. I was always satisfied with both in the combinations I built over the years.

Alex's car is quite impressive, both in appearance and numbers...I have a lot of respect for class racers. Before I adjusted the instant center with my four link, my car used to do the same thing (with an 8" converter)...I got tired of cracking shock towers so I altered the four link and put struts on the car. Not nearly as impressive but, for me, a heck of a lot less work and more consistent. Kinda like driving a grocery getter, except exceedingly fast..*G*

Next problem?? *G*
 

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I would think that with your setup, that wasted (but visually impressive) motion would translate to quicker et.

I'm kinda glad I didn't get the racing bug 20 years ago. Aside from having fun and spending $, I would probably have missed out on a great wife and two beautiful urchins. I suspect that my son may one day want to do something along these lines (cars) and I hope to be able to be some help to him.

Later.
 

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You're right, the ET's were marginally quicker (less than .05 seconds consistently) but my RT's were all over the place and I would often red light from lifting the tires out of the beams before moving forward. I just didn't have the time or patience to dial everything in like Alex has. In bracket racing, consistency is more important than speed/ET so I've always built my combinations with that in mind. I operated the race car as a business for many years and I guess one is supposed to make money with a business, eh?? *G*

BTW, I was single until getting married 2 years ago for the first time....I figured 20 years of playing was enough..hehehe...

Hope your son gets the bug....it's a great way to learn about life..
 
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