actech

just installed a new 83mm pulley from EC. i know what the pulley gap should be but my problem is my gap is way too big even without shims. my feeler gauge goes to .601 and that fits without touching. it is rather cool today in the dallas area, about 45, and my car has been sitting for several days so everything is cold. i dont know if this will be an issue as i cant get the pulley any closer. anyone run into this problem? i assume it may change once car is hot? im searching the forums as i post this but cant find anyone that had this big of a gap. thanks in advance for any input given.

w

05-E55

I recently installed UPD 83mm and have a similar issue. Have you been able to resolve it?

cnterline

BRH AMG

I think he means .6 mm or .024". I bought one of these and I had .039mm, so I contacted Shadul before I ran it and he told me to run it. He said after about 500 miles it would tighten up.
After 600 miles it was still .039" , so I contacted again and told him about and he said to send it back. I told him it was now used and he said it would not matter. Waited for over a month
expecting a new or repaired pulley but had not received anything so I contacted him again. He said he would handle it. So two weeks later I received my same pulley back and re installed
it with no shims and it measured .039.... Now all I have is a $400.00 paper weight. Good luck.

05-E55

This is not what I wanted to hear, but thanks for your input.

Here's mine.

BRH AMG

[QUOTE=BRH AMG;7642234]I think he means .6 mm or .024". I bought one of these and I had .039mm, so I contacted Shardul before I ran it and he told me to run it. He said after about 500 miles it would tighten up.
After 600 miles it was still .039" , so I contacted again and told him about and he said to send it back. I told him it was now used and he said it would not matter. Waited for over a month
expecting a new or repaired pulley but had not received anything so I contacted him again. He said he would handle it. So two weeks later I received my same pulley back and re installed
it with no shims and it measured .039".... Now all I have is a $400.00 paper weight. Good luck.

BRH AMG

Sorry double post... was trying to correct spelling. I ran my pulley that way. I had Anthony from Race IQ come up and dyno tune it that way and only saw 11.9 psi boost. I got another pulley from someone else and With .016" gap and made 13.8 psi boost. Both tests with the belt wrap kit and it picked up 25 RWHP. It will likely slip and lose boost if you run it that way

tw2

This is probably quite a common issue. Mine is just outside the range and I have been running it as is with no shims.

SICAMG

Running the pulley will not tighten itself up and If anything the gap will open up slightly over time.
The pulley can be fixed as I have done it before through my machine shop guy.

MSG 55G

How do go about finding a machine shop guy in my area? What do I search for?

tw2

I presume they take a fraction of a mm off the mating surface at the centre only at the back of the pulley?

SICAMG

Yes off the back side on the bearing. You only need 10-15 thousands to get where you need to be.

cnterline

SICAMG

Cnterline is right. Everyone thinks that if the gap is to wide that it will slip. If it did it would destroy the pulley/magnet surface under heavy load of engagement.
It is not good for the connecting straps and can cause them to fail prematurely.

actech

so been busy sorry i havent dropped in. so initial gap was .7mm which is supposedly to big. after driving it that way for a bit gap came closer to spec. now however the pulley is in almost constant contact with drum even when car has sat for a few days. spin pulley and it drags on drum and they both turn. i have zero shims and didnt have any before but i just ordered some on ebay for $20, four shims two different sizes .20 and .30 i think. i drove it today without the belt on sc since its basically always engaged. man was it slow. i assume the sc was still spinning due to vacuum?

05-E55

Genuine question; if it "doesn't matter", why is there a specified range stated, even in the included UPD install instruction sheet?

SICAMG

It does matter but for different reasons. Will it work with "off" end gaps that are to wide.....yes. But lets look at it this way.
Look at post # 5. and imagine that that feeler gauge in the picture is 1/4 inch thick and that's how far the back plate needs to travel to reach the magnet. Those 3 metal straps will now have a bent "twist" to them when engaged and have a much better chance at failing. If the travel was 15 thou. than they would be practically straight and the most strongest and that's what you want.

05-E55

Not being particularly mechanical, I think I understand what you're saying and it seems logical. Too much gap will place too much strain on the springs and potentially cause damage. Which is also why I'm concerned about the larger than spec gap in my pulley as the picture you referenced shows. That's the largest gauge I have, .889 and slides right in all around.

actech

so something else i just noticed that might make this even more confusing. i currently have two 83mm pulleys in my hand and noticed that on both pulleys the bearing is not 100% bottomed out within the pulley. i know there is a groove where the C clip locks into hold bearing in pulley but is there a lip at the bottom to stop the bearing from fully seating? if there isn't is there any chance that when the pulley and bearing heat up that the bearing actually moves slightly back and forth and this could be causing the erratic differences in gap size? i hope that makes since im on some meds that are making me a little fuzzy so sorry.