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Discussion Starter #1
I first put my blower on about a year and a half ago, and when i did the whine from it was LOUD! And I loved it. While putting the engine back together a friend didn't put 2 spark plug wires on all the way and shortly after the rings in those 2 cylinders blew. I needed to replace the bottom end with with stronger pistons, rods, and rings anyway so it really wasn't that bad. Fast forward a little over a year and i have everything done and put the it all back together and the whine is NO WHERE near as loud as it was. Before, when the engine was idling you could hear the whine over the engine. Now, the only time you can really hear it is when the car is decelerating from a high RPM. Its the same blower and same belt. Does anyone have any idea why this would happen?
 

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I've always heard that allot of the whine in a roots type is from the belt and pulleys. The pulleys with holes drilled in the root of the belt contact are supposed to run quieter. My guess is that the internal gears that drive the lobes also play a part and that straight cut would run louder than helical cut.
Is it possible that the motor is louder since the rebuild and covering up the supercharger? Some flex fans, most gear drives, and quick change rear difs will make similar noise to a blower.
 

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Belt tension has alot to do with the whine. The belt may of been way to tight before causing all the noise. If you want the whine back add more tension. Just be warned, its not good to have that much tension on the belt. It'll cause undue stress on the blower drive and crankshaft hubs.
 

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On the straight part of the belt you should have between 3/4 and 1 inch of movement. Take a straight edge and hold onto the belt and push the belt in and messure it. Any tighter than that it will put a lot of stress on to the bearings in the blower. Any looser than that the belt has a chance of flying off or bumping teeth.
 

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While putting the engine back together a friend didn't put 2 spark plug wires on all the way and shortly after the rings in those 2 cylinders blew
Plug wires causing ring issues..........hmmmm.
 

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Discussion Starter #7
Plug wires causing ring issues..........hmmmm.
i just know that when we went to pull the the plugs to check the compression in each cylinder when it started not to run right, those two plug wires werent on all the way.. and the rings in those two cylinders blew..
 

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Discussion Starter #8
Belt tension has alot to do with the whine. The belt may of been way to tight before causing all the noise. If you want the whine back add more tension. Just be warned, its not good to have that much tension on the belt. It'll cause undue stress on the blower drive and crankshaft hubs.
ive tightened and loosened the belt over and over..
 

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Discussion Starter #9
On the straight part of the belt you should have between 3/4 and 1 inch of movement. Take a straight edge and hold onto the belt and push the belt in and messure it. Any tighter than that it will put a lot of stress on to the bearings in the blower. Any looser than that the belt has a chance of flying off or bumping teeth.

yea, its right where it needs to be..
 

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those two plug wires werent on all the way.. and the rings in those two cylinders blew..
You could hold the plug wire away from the plug and it should still fire just fine; having them not quite jammed into place isn't going to cause a problem.
And what exactly is a "blown ring"? Can't say I've ever seen one. I've seen worn rings, and worn out cylinder walls, rings that have broken in multiple pieces,.........
 

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Discussion Starter #11
You could hold the plug wire away from the plug and it should still fire just fine; having them not quite jammed into place isn't going to cause a problem.
And what exactly is a "blown ring"? Can't say I've ever seen one. I've seen worn rings, and worn out cylinder walls, rings that have broken in multiple pieces,.........
there was enough damage to the ring to compromise the seal and allow blow-by.. thats kinda beside the point really..
 

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Hi, just curious:rolleyes:, what's your engine set up, type of pistons, rods, heads, compression ratio etc? I want to put a blower on my engine one day but think compression ratio is too high:( 9.6:1 at the moment.
 

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Discussion Starter #13
Hi, just curious:rolleyes:, what's your engine set up, type of pistons, rods, heads, compression ratio etc? I want to put a blower on my engine one day but think compression ratio is too high:( 9.6:1 at the moment.
i cant find the paper that lists all of my internals, but i will look around and let you know if i find it.. but i do know that we used the heads off of my dads 81 corvette with 76 or 74 cc cumbustion chambers and my engine guy put in (i think JE pistions) that dropped my compression ration to about 8.1 to 1.. my compression was about yours before and he was tellin me with the compression that high you can barely run any boost.. im not a super mechanic or anything but my engine guy has built thousands of motors and used to drag race professionally.. i also installed a comp cams nitrous cam with 507/525 intake/exhaust lift which allows more exhaust to exit and is better for nitrous or forced induction engines.. all of my internals are forged though.. and thats about all i can remember, like i said if i can find my paper i will give u better details.. hoped i helped a little..
 
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