Belt slip common
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Instructor
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From: evansville in
Belt slip common
I was on the dyno yesterday for the first time and I was getting what i think is belt slip above 4800. It hit 8lbs at 4800 and then slammed hard back to 4-5lbs and stayed there untill redline. I have an Ecs novi kit and the tensioner is bottom out. Are the belts they send too long? The tuner said that the belt was slipping.
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I was on the dyno yesterday for the first time and I was getting what i think is belt slip above 4800. It hit 8lbs at 4800 and then slammed hard back to 4-5lbs and stayed there untill redline. I have an Ecs novi kit and the tensioner is bottom out. Are the belts they send too long? The tuner said that the belt was slipping.
Melting Slicks
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From: Macomb MI
St. Jude Contributor
Funny this topic should be posted, my belt just fell off this morning. Went out to get the paper and decided to check how much boost I was registering ( Just added Alky ) Dam it didn't make it past 8lb and it sound like it back fired, pulled over and the belt was off, not broke just fell off? WTF I hope this isn't the beginning of what's to come. I don't have 2000 miles on this Novi system since it was installed. Does it sound like the belt stretched and just fell off?
Le Mans Master
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Do you have the ECS idler on the driver's side? If so you probably need to move the bolt over one hole. The middle hole worked fine for my install. I have roughly 500 miles on it and have seen 10 lbs boost a few times. It will be on the dyno tomorrow so we'll see how it holds up there.
Melting Slicks
Joined: Nov 2003
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From: Macomb MI
St. Jude Contributor
Not sure, don't know all the particulars. I did have a local tuner who has installed a few of these systems. Not sure what happen, belt stretched, something out of alignment. Perhaps I need to update a part, just hope he has time to get me up and running. This sucks big time.
Le Mans Master
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From: Metro Detroit Michigan
Geez, you guys are freakin' me out! 
buddah98, I had a sudden drop of 4 pounds in boost yesterday, but it was because I blew off a charge hose. I'd just had it apart, and didn't tighten something enough I guess.
Is it possible to route the belt incorrectly and wind up with the wrong tension? In any case, the tensioner shouldn't be bottomed out. I just replaced the belt and an idler yesterday (bearings on the idler were fine, the aluminum belt surface had worn) and had about 1/2 inch between the stops on the spring tensioner when I got done, and there was further tightening available on the head unit idler. With the year-old belt, I had about 1/4 gap at the spring tensioner.
I'm just taking wild guesses, because my system's been on for three years without significant problems, and there may have been some changes in the interim which will make yours work differently.
Sponge Vette, don't get discouraged. These systems can work!
buddah98, I had a sudden drop of 4 pounds in boost yesterday, but it was because I blew off a charge hose. I'd just had it apart, and didn't tighten something enough I guess.
Is it possible to route the belt incorrectly and wind up with the wrong tension? In any case, the tensioner shouldn't be bottomed out. I just replaced the belt and an idler yesterday (bearings on the idler were fine, the aluminum belt surface had worn) and had about 1/2 inch between the stops on the spring tensioner when I got done, and there was further tightening available on the head unit idler. With the year-old belt, I had about 1/4 gap at the spring tensioner.
I'm just taking wild guesses, because my system's been on for three years without significant problems, and there may have been some changes in the interim which will make yours work differently.
Sponge Vette, don't get discouraged. These systems can work!
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From: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
We only use one belt size on every kit, including the ones that just went 10.0's at the nationals. Something is not adjusted right, make sure you have the tensioner opened to almost 12 o'clock.
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From: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
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Instructor
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From: evansville in
The tensioner was at the 2 o'clock position, so thats probably it. What is the best way to get it back to 12. Do i need to take the belt back off? Should I loosen the head unit tensioner all the way back up?
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Feel free to send me pics if that helps.
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Le Mans Master
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Doug, since the mounting holes behind that PS idler are hard to see, can you give us the correct distance between the idler and the straight section of belt running above it if the idler is mounted in the correct hole?
For instance, mine has a gap of about 3/4 inch. Is that about right?
Also, is there a difference in spring tensioners used on the Paxton kit?
Mine (3 1/2 years old) works fine at 1 or 2 o'clock. Is it the same piece as the one you'd like to see at 12 o'clock?
For instance, mine has a gap of about 3/4 inch. Is that about right?
Also, is there a difference in spring tensioners used on the Paxton kit?
Mine (3 1/2 years old) works fine at 1 or 2 o'clock. Is it the same piece as the one you'd like to see at 12 o'clock?
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From: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
Doug, since the mounting holes behind that PS idler are hard to see, can you give us the correct distance between the idler and the straight section of belt running above it if the idler is mounted in the correct hole?
For instance, mine has a gap of about 3/4 inch. Is that about right?
Also, is there a difference in spring tensioners used on the Paxton kit?
Mine (3 1/2 years old) works fine at 1 or 2 o'clock. Is it the same piece as the one you'd like to see at 12 o'clock?
For instance, mine has a gap of about 3/4 inch. Is that about right?
Also, is there a difference in spring tensioners used on the Paxton kit?
Mine (3 1/2 years old) works fine at 1 or 2 o'clock. Is it the same piece as the one you'd like to see at 12 o'clock?
The tensioner has not changed in 6-7 years, actually they do not go to exactly to`12 o'clock, so twelve thirty- one oclock is fine.
The easiest way to see if it was placed in the highest point is to look at the W.P. bolts and see if the idler has enough room to go up another hole or not. If it is a 1/4" away then your good.