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Is is me or does the firing order difference between the 302 and the 351w make the exhaust sound totally different [not tone, but pulses]? The 351 sounds more "thumpy" and intermittant than the 302/289 to me. Opinions on this?
 

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There's WAY too many factors involved, to even speculate on that - cam profiles, condition of the exhaust systems, exhaust pipe sizes, routing, mufflers, condition of the cats... there's more, but you get the idea
 

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Discussion Starter #3
I'm running stock motor, 30" glasspacks with less that 5 ft. total length. It doesn't sound anything like any 289/302 I've ever had. It blabbers all offbeat like a harley in comparison.
 

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I used to think the difference in sound had something to do with the firing order, but I can't see why. I sat down a while back and figured it, and if you look at each bank (left and right header), the exhaust pattern on both is still (every 90 crank degrees):

Psgr: fire wait wait fire wait fire fire wait
Drvr: wait fire fire wait fire wait wait fire

This is the same for both the old 302 (1-5-4-2-6-3-7-8) and 351/302HO (1-3-7-2-6-5-4-8) firing orders. The only difference is where in the cylinder sequence the pattern starts. On the passenger side header, the F-W-W-F part of the sequence starts with 3-7-8-1 on the 302 and 2-6-5-4 on the 351. Otherwise the pattern in each header is the same, and the two headers coordinate the same (i.e. not out of phase or anything).

I have to think the differences are mostly in cam timing. Most 351W's came with a more radical cam than the truck 302's, and are closer to the 302HO cam. I can almost always tell the difference audubly, but that's the only reason I can think why. I don't see any way it can be the firing order.
 

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Chuck said:
I used to think the difference in sound had something to do with the firing order, but I can't see why. I sat down a while back and figured it, and if you look at each bank (left and right header), the exhaust pattern on both is still (every 90 crank degrees):

Psgr: fire wait wait fire wait fire fire wait
Drvr: wait fire fire wait fire wait wait fire

This is the same for both the old 302 (1-5-4-2-6-3-7-8) and 351/302HO (1-3-7-2-6-5-4-8) firing orders. The only difference is where in the cylinder sequence the pattern starts. On the passenger side header, the F-W-W-F part of the sequence starts with 3-7-8-1 on the 302 and 2-6-5-4 on the 351. Otherwise the pattern in each header is the same, and the two headers coordinate the same (i.e. not out of phase or anything).

I have to think the differences are mostly in cam timing. Most 351W's came with a more radical cam than the truck 302's, and are closer to the 302HO cam. I can almost always tell the difference audubly, but that's the only reason I can think why. I don't see any way it can be the firing order.

You definatly had a lot of time on your hands that day.:popc1:
 

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Actually, I sat down and refigured it before I posted that just to make sure. Only takes about five minutes when you know the firing orders already. Maybe I should get out of the garage for a while, huh? :brownbag :toothless
 
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