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Just curious about this. I don't know what happens when the exhaust manifold bolts loosen up. I would think that it would just be an exhaust leak, and not harm the engine, but not sure. Anyone enlighten me??
 

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revspan said:
Just curious about this. I don't know what happens when the exhaust manifold bolts loosen up. I would think that it would just be an exhaust leak, and not harm the engine, but not sure. Anyone enlighten me??
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Nothing happens. I was wide open throttle in the middle of vermont when all of a sudden started getting real loud. Pulled over and notice all 4 bolts gone on one side of Y-pipe and gasket blown loose. Limped back 10 miles to trailer. Had the dealer put it back together just n case anything did go wrong. Still runs great.
 

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BuzzMXZ said:
revspan said:
Just curious about this. I don't know what happens when the exhaust manifold bolts loosen up. I would think that it would just be an exhaust leak, and not harm the engine, but not sure. Anyone enlighten me??
[snapback]685914[/snapback]​
Nothing happens. I was wide open throttle in the middle of vermont when all of a sudden started getting real loud. Pulled over and notice all 4 bolts gone on one side of Y-pipe and gasket blown loose. Limped back 10 miles to trailer. Had the dealer put it back together just n case anything did go wrong. Still runs great.

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I'm not sure if it would, mine went down last night, with the stock jetting the 05-06 is waay lean in the midrange, and any change in the backpressure negative or positive could have negative results. Mine went down in the midrange, approx 6700-7200. Wasn't ice.(Always run iso), not hot, Thing is I never had the check engine light come on at all. The only thing no stock is the head and can(SLP). I did shim the needle, so it was a little richer than stock, RKT head for 87-91 octane. Same comp ratio as stock. Mag piston is toast, head and pto fine. I havent checked my carb boots yet. Oh well, covered under warranty.
 

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lower back pressure is going to cause problems. The side that I had a missing bolt had a lot of carbon built up on the valve and carbs weren't as clean as they should be(wifes sled). Had a lot of crap blown all over the place and must of got into the airbox and into the carbs. Did the airbox fix and fixed the missing bolt.
 

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Lower back pressure means more airflow. The gas flow is still the same, resulting in a lean condition.
If it's really cold you could have big problems continuing to run it that way.
 

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Thats exactly why my 06 500ss burned down last weekend. The Y pipe came loose and the eng. leaned out and locked up tight. Dealer said all the bolts were in the belly pan and had to fish them out with a magnet. Got real loud seconds before she blew. By the time I let off it was toast.
Now it sits in the shop and all my buds are out in the UP. since last fri. having a fuking blast.
Thanks Doo!
Bolts have been holding exhaust manifolds on for many decades. You think Doo would of figured this issue out by now! SAFTEY WIRE?
 

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Ripcord said:
Thats exactly why my 06 500ss burned down last weekend. The Y pipe came loose and the eng. leaned out and locked up tight. Dealer said all the bolts were in the belly pan and had to fish them out with a magnet. Got real loud seconds before she blew. By the time I let off it was toast.
Now it sits in the shop and all my buds are out in the UP. since last fri. having a fuking blast.
Thanks Doo!
Bolts have been holding exhaust manifolds on for many decades. You think Doo would of figured this issue out by now! SAFTEY WIRE?
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Mine never got overly loud, just crusing down the lake playing with the throttle a little(no drastic changes) and down it went. The speedo and tach froze at 34 mph and 3500 or so rpm. The mag side is toast. I've blown many engines and this has to be one if the worst. Alot of aluminum in the cyl, I mean alot. Top of piston has alot of aluminum chunks on it. Plugs were nice darker tan color, 3/8 to 5/8 " wash all around. Lots of carbon. Almost looks like too much heat in the pipe ? Does the SLP can hold alot more backpressure than the suitcase ?
 

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I say bull"edit for bad language"!! Its just a lame dealers excuse when they dont know the real reason.. These sleds are jetted richer than needed anyway, especailly this season unless youre at the north pole on a clear night. Youd have to have the y pipe fall right off the sled to move enough extra airflow out to lean it enough to seize it and even then I think its questionable since you couldnt stand the sound long enough to stick the piston.
 

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I had one side of my y pipe loose all the bolts and dropped the gasket. I ended up just riding the pissout of it the rest of the day(I know, not too bright). It ran seemingly fine, just f'ing loud for a while. Then it started loosing top end. I replaced the bolts and gasket. Still having the same problem. Did a compression check. Both sides only 75#. Seems strange that it runs perfectly up to 3/4 throttle with that low compression. Think I toasted it?
 

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The reduced backpressure...

That means your raw air/fuel mix blows right out the exhaust instead of being held (for lack of better word) in the cylinder by the hot gasses from last cycles burn before the piston goes up enough to block the port.

So you end up running lean and kaboom!

Make sense?
 

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06MXZXRenegade800 said:
The reduced backpressure...

That means your raw air/fuel mix blows right out the exhaust instead of being held (for lack of better word) in the cylinder by the hot gasses from last cycles burn before the piston goes up enough to block the port.

So you end up running lean and kaboom!

Make sense?
[snapback]716610[/snapback]​
no
 

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t600horev said:
06MXZXRenegade800 said:
The reduced backpressure...

That means your raw air/fuel mix blows right out the exhaust instead of being held (for lack of better word) in the cylinder by the hot gasses from last cycles burn before the piston goes up enough to block the port.

So you end up running lean and kaboom!

Make sense?
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no
[snapback]716639[/snapback]​
Yes
 
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