mine used to fit right over the inlet, but not any more

big bos, i don't think it's slipping, could just be breaking in dust fromthe belt, or even dust from the groove.
oh, and your cover is totally different than mine, it sticks out farther on your idler. it even seems that the idler is bigger in diameter ( but not really sure on that).

 

Chris and I were talking about your belt tension Brian, his is very tight. So what might be happening is when you blip the gas the belt might be skipping and jumping off. I know his earliest setup would do something like that when he was runnign a stock spring loaded tensioner that was not keeping sufficient belt tension... But I'm repeating what I recall from two years ago, best thing is to double check with him.

 

Its more dust then just breaking it, its slipping dust because it was on the stand off's coated pretty much...

I spaced the idler out different today and moved it slightly close in towards the bracket.......that helped get it away from that dust cover, but the tightest I could get the belt underneath the car was a little under a 1/2" of tension.....I drove it around like this for about 20mins, then blipped the throttle a few times and it still gave the same feeling......

Also, I ran out of gas as I pulled into my garage...........******* great......

I put A LOT of fuel in my car and didn't think the gauge would be this off......fuel pump started making a lot of noise and the regualtor was making a whirling noise, as I was PARKING THE CAR in the garage fuel pressure dropped to 45psi and stayed there, so I shut off the car right away.......my 420L single sounded different till I primed it a few times......car didn't have any problems started up and idling, should it be oK?

 

All I know is mine is pretty loose and I haven't had the belt skip. I did some testing on the freeway today while testing out the digital boost gauge and there was no funny noises or vibrations when I got in it, just threw me back in the seat when the boost comes on.?? Call lee tomorrow, ask him how tight the belt should be. Having a cog belt very tight goes against what everyone told me about them. Lee told me to have the cog belt hand tight when I first bought my kit. The dynoguy told me if I ran it too tight, the belt would be toasted very quickly.
J

 

forcefed, i am only passing on fragments of comments that Chris aka Z8s said so I don't want to be incorrect, but he does have a cogged 4th gen and not a cogged Barracuda or other app.

 

I am going to put the car up on the lift monday if possible.....

If the belts are jumping teeth at a 1/2" tension, wouldn't it be worse even more loose?

I can get more tension on the belt and get it possibly down to 1/4" tension if I put it up on the lift and really get at it.....

Any suggestions.....

 

**** I am just as confused as you guys, I really wouldn't second guess Z8's advice at all, I am just really confused at what i've been told. My belt has been check by three different people(stang guys who know cog set ups) and after the inital adjustment they told me it was good. I definately don't know at this point??? I do know that my boost didn't drop at all on the dyno which leads me to believe that my tension is right, the only wear on the belt was on the edge that was hanging off the s/c cog???
J-time for one of these

 

I'm confused as well about the situation..........need to figure it out though, If all else fails and I can't tweak it, I'll wait for sikora, and let him do the rest........I think everything is alinged, just can't figure out why its jumping......

Anyone think if I loosen the belt to 3/4" it could get better or no?


It seemed like it was somewhat better today slipping wise, but nothing progressivly further with the situation, Its got to be jumping for some reason, and I can't for see it holding better w/less tension....

My mototrons will be here this week.........

Just need to get these COGS straightened out.....

 

Too add more to the confusion here is an email from a guy who makes custom cog set ups for LT1 cars with Vortech or ATI's

Hello Jeremy
Regardings your cog belt you should tension it too tight but not super
tight. 3/4 to 1" are fine. The only way you will loose a belt is that when
you go WOT and have a backfire that where you will loose a belt (striped the
cog teeths) So make sure your car is tuned.

Bruce

So I am going to stick with the amount of tension I have now for the time being. I will go tighter if the car shreads the belt.
J

 

UPDATE:

Took the car out this morning, fuel system seems to be fine, put another 5 gallons of 100 in the tank....so thats A ok......

When I was at the gas station I was reving the motor by hand under the hood.....and I was watching the whole COG setup while doing this.....as the motor torques to the side I can see the belt elevate from the blower pulley, its not slipping on the crank, just on the blower pulley........when the motor dives to one side it jumps off the blower pulley, then as soon as I let the throttle body go its back on again.......the belt is wearing fine just driving it around town.......but I was doing little throttle revs to 3K real fast and that seemed to make it jump off.........

It almost seemed as if the blower was moving somewhat and this could be possibly throwing the alingment off.........not exactly sure though....

I'll measure the tension when I have it on the lift tonight, see if I can make it any tighter......

I talked to Sikora on the phone, he might be able to get me in sooner than I thought, but if the alingment of these pulleys is off by 20 thousandths it could make it a problem...

 

Well I got it as tight as possible tonight, less than 1/2" for sure, I saw 4psi on the gauge and I felt the belt skip once or twice tonight w/some testing......but all depending on how I throttle it the belt acts different...if I stab it it slips, if I get into it it grabs......

I can't got WOT because I don't know if I currently have the fuel to support that, and the car isn't tuned.......so I don't want to take any chances.........

 

Brian I was talking to Chris and he said he suggested you run the belt differently around your idle, what did he mean?

Again, when I read these cog threads I think that nobody seems to have the best handle on it yet until we see some numbers.

 

He is talking about running the belt under the tensioner how it is supposed to be ran.....

I'm running it over like Jeremy....I have not yet tried running it under, but I think I will run out of room to tension the belt......me and chris were talking about opening up some more space in the bracket for the idler cog pulley to have more room to move either up or down.......what ever we decide on....

Either way I know we can get it to work.......just needs some tweaking....

 

Yeah I can see that working the best, but with the way ATI mounted it. The tensioner for the cog, hits the stock idler pulley when trying to push it up and out of the way to get the cog belt ran underneath it. I ordered a new belt, and when it comes(tomorrow,hopefully) in I am going to add about two more spacers to the standoffs to push the bracket out even further to clear the stock idler and be able to push the ATI/cog tensioner out of the way. This is where the limited belt lengths come into play, we need one that is just 1/2 to 1 inch longer than this one but there is nothing available between the size we have 960 and the next size 1040. I am sure I will get it figured out soon. I already elongated the tensioner slot on my bracket to lift the tensioner higher(clint had to do this to his) and Boss might need to do that too.

There is such a small distance from the s/c cog and the crank cog(10.5 inches) that running the belt on top of the tensioner even though it works, doesn't provide the belt wrap needed to keep it from lifting on the s/c on a quick rev. I haven't expirenced this but Bos has. So getting it to run normally is the best way, I'll have it figured out tomorrow.
J

 

I was looking at it when it was up on the lift, I know I can run the belt underneath, but it involved slipping the belt off the crank pulley..........now with some force I was able to get it back on w/out taking the blower off........

I wasn't excited about taking the blower off to put the belt back on when I had accomplished nothing......I tried pushing as hard as I could to get the tensioner to the top of the slot, I don't think I can push it any farther up, I can't tell for sure though if there is room left to move......I can only go so far before I hit that stock idler...

Like you said, having the belt under would provide more wrap and no worries w/the damn idler.....

 

So you were able to get the belt off by slipping off the crank cog, that rocks. I gotta try that. Hopefully I then will be able to run it normally. I'm with you I hate taking the s/c down everytime I need to mess with the belt. It just sucks.
J

 

Yea, you just really got to stretch that belt to try and get it back on, I used the backend of screwdriver.....

 

Nope it isn't going to work, I got the belt off like you did and even ran it under the tensioner. Then I ran the tensioner up the slot to the highest it would go(I even have it lengthened) and I could not get the belt back over the crank cog at all.

I got it up as far as I could with the handle of a 1 inch ratchet(fits better between my trannylines and crankcog). Then tried to turn the engine over to force the belt on that way. NO DEAL things got tight in a hurry and started to put some stress on things. So I backed it off and put it back on the way I had it.

BUT the solution is pretty easy, open up the tensioner slot even more. I thought I had it opened quite a bit but it has to be opened even further.
I have plenty of space between the tensioner and idler
You have to look close...


That looks to be the ticket.
J

 

Yea, I'm right there too, if I take my ONE washer out that I have spacing the idler now it will bring the idler too close to the bracket and that will cause the belt to hang off the crank pulley...it hangs off now, but its not a problem......

I might have to have that one side of the cog idler machined down to clear the stock idler.....doing that and adding space in the bracket to move that idler up even more should give me more tension....

Jeremy, was the original problem w/running the belt under the tensioner is that the belt wouldn't fit or was it that there wasn't enough tension? I e-mailed lee on my side of the story, he hasn't gotten back to me yet......

 

The original reason why it wouldn't fit was that the belt is too short. If it was 1/2 or and inch longer the tensioner would work like it was suppose to=perfect.

Now if I wanted to get more space between the idler and tensioner thats an easy fix too, I just have to add one more washer to the standoffs, to open it up more than what I show in the pics.

If you lengthened the slot and added a washer or two to each stand off you will get the space between the tensioner and idler that you are looking for. You will also be able to run the belt like it was supposed to-under the tensioner.
Hope that helps. The real question is how much more do I need to lengthen that slot, I am thinkin about a lil more than .5 inch.
J