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By oldguy - 14 Years Ago
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I have been reading lots of info on the web over the last several months.... maybe too much.I thought I ran across an artical about a reground camshaft that was used to change the firing order of the yblock, and now cannot find it. Does anyone have any info on this? Or was I dreaming and haveing a bad nighmare thanks
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By mctim64 - 14 Years Ago
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Why change it? That is one of the things that give it it's appeal. Besides the scrub guys are coming over to it now with the 4-7 swap cam. 
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By GREENBIRD56 - 14 Years Ago
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Oldguy - Before you get totally freaked out by Tim's revelation - be advised the the cylinder swap he refers to.....is being described by the bogus GM cylinder numbers - not their proper Ford equivalents...... When you get that sorted out (re-label everything to the correct Ford numbers) then you discover that all of the GM race motors eventually get converted to the early Ford V8 set-up. The Y-block shares its firing order with the Ford flathead - which only has 3 main bearings and had to have a nice "smooth" torsional loading sequence to survive. Our Y's have five bearings and benefit from the same beneficial firing order. Has to do with which cylinders are making power - and which ones are compressing air, and where they are relative to the flywheel flange....... I learned this from Ted - who is the keeper and understander of this wisdom.......
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By mctim64 - 14 Years Ago
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Steve has explained it very well, I guess I should have gone into more detail but at the time I just couldn't believe anyone would want to get away from the firing order that has become the "go to" for performance. I kept my reply short to refrain from a rant. 
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By Pete 55Tbird - 14 Years Ago
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While we are on the subject of firing order in a Yblock, can some tell me the firing order of a reverse rotation marine engine? Just curious. Pete
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By yalincoln - 14 Years Ago
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it should be the same only in the other direction.
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By yalincoln - 14 Years Ago
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sorry, that's wrong. it would be reverse fireing order with the valves opening oposite, intake first.
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By Ted - 14 Years Ago
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The Argentina Phase II Y-Blocks used the 289 SBF/ 390-428 FE firing order. This was to accommodate using cylinder heads that mimicked the SBF heads in valve layout. As Steve & Tim mention, the hot setup for the scrub engines is the 4-7 cylinder swap which effectively makes those engines having the same firing order as the Ford Y-Block and the Flathead Ford V8. The new Mustang 412HP Coyote 5.0L V8 (normally aspirated, non direct injection) also uses the Y-Block firing order so it looks like the firing order has now made the full circle.
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By oldguy - 14 Years Ago
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Thanks for the input on the firing order post. As I was saying, my reasoning behind the change was that it improved the performance of the yblock. I cannot for the life of me remember the details, but at the time I thought it sounded like a good idea. Maybe it was a bad dream. As for the exhaust sound of a yblock, yes, it is unique compared to other engines, to say the least. For me, not better, not worse, just different. Hope I am not stomping on toes on that thought.
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By Y block Billy - 14 Years Ago
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I beleive John Mummert did an article on the firing orders in the Y block mag back some time ago. The Y block firing order produced the most horsepower, the SBF was the smoothest, The Scrub order it was baffling as to why it come about because it wasn't good for anything. Thats why the Nascar scrubs were making the swap to the Y order. Michael Waltrip got caught and fined for it a few years ago. As you mention it may have been a bad dream because the Y is best as it is, its the other brand that needs help.
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By Pete 55Tbird - 14 Years Ago
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I will ask again. Can anyone give the firing order of a reverse rotation marine Y block. And please, not just the standard one backwards. REAL NUMBERS of real cylinders. Thanks Pete
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By MoonShadow - 14 Years Ago
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For some reason I thought they were the same as normal rotation. I had one of them but didn't think to check the firing order. If my understanding is correct its got a solid timing gear that turns the cam and distributor in reverse. Thats the best I can do, sorry! Chuck in NH
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By YellowWing - 14 Years Ago
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Y-Bock reverse rotation firing order is 12736845. Hope this helps. Link to answer http://www.marineengine.com/boat-forum/showthread.php?386813-312-reverse-rotation-firing-order
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By Hoosier Hurricane - 14 Years Ago
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So if you read the marine firing order backwards it IS the same as the regular Y. Interesting.
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