once again another question. anyone running the 928m impeller with the 2.87 pulley. to my understanding this is overspinning the bearings. where can one buy the abec7 or 9 bearings other then ebay? only place ive seen them

 

I will be... There are also some on here running the 928 w/ 2.87, 2.67 and 2.75 ... Not sure if they are using stock bearings, 928's bearing kit, or aftermarket race berings however.

I will also be running an ATI damper which will contribute to overspinning as well so it will be interesting to see how it all rubs out in the wash.

(ps) I'll find out more on the SSV this week and when they can take it off, I'll let ya know on that.

 

ive been in contact w vortech and 928m and they are both trying to see what can be done. the 928 bearing kit (the rebuild kit) they sell is the same as factory bearings so they are not rated to spin at higher rpm. the seal is but not the bearing. waiting on carls reply to see what can be done. i see alot of people talking about upgrading to the APEC7 rated to 60k(if i remember)or APEC 9 rated to 65k. just not sure from where.

and deff just let me know!

 

http://www.flickr.com/photos/j-franco/8528924699/http://www.flickr.com/photos/j-franco/8528924699/ by http://www.flickr.com/people/j-franco/, on Flickr

got a little time after work today so pulled hood and bumper and a couple little things here and there. motor is still 6-8 weeks away from kyle at ipp sending it but might as well prep. also prob pulling blower soon to send it off once i get my answer on the bearing issue. worst case scenario i keep overworking the bearings as i already have been with the stock blower n the 2.87

 

How do you get air to your oil cooler? Thinking about doing a similar setup...

 

Bearings

Vortech bearings are ultra-high precision (ABEC 7/ABEC 9) pieces that originate from the best precision bearing manufacturers in the world. Most are custom manufactured to our specifications. Aircraft quality is truly an understatement here, since these bearings experience speeds as much as twice that of a jet engine.

 

So then with that being said, Vortech / 928 bearings can handle the overspinning to a certain extent and one would not have to worry about a re-build for lets say a year or two? Just have to budget for it as a routine maintenance.

 

The heck are those donk a$$ wheels doing there? Cannot unsee.

 

there going on the Z!!!!

my roomate has a tahoe and is into car audio n such. thats his thing.

 

pulled the left reflector gets pretty good air threw it. havent had any issues with where its mounted

 

You said it so now I want to see it, I want to see it.... I WANT TO SEE IT!!

Get that thing LIFTED and then I want to see it crush cars!!

 

dont see that happening :-p . so after talking to carl more he had no real solution to the bearing issue other then not to overspin the bearing, i asked if they installed or would install "upgrade" bearings and he would not, and does not. so i guess the option is to either overspin the bearings or dont run the impellers w the 2.87 at high rpms. going to be contacting superchargerrebuild.com (i think thats the website) they claim to install high speed bearings and see what they have to say. vortech also gave me about the same answer for the SI trim.

 

realistically, you will only be overspinning at the top of your rpm range. you are there for a very short period of time, not to mention the inherent belt slip at those levels.

After almost 10 yrs on the market, i dont think there has been 1 person with bearing issues due to overspinning or the impeller coming apart.

 

Yeah, I think of like boosting a turbo out of its efficiency range. There are tons of guys with factory turbo cars running almost double the factory boost with basically no problems. Yes, turbos and superchargers are different, but they both still rely on bearings and if both are pushed hard in a daily-driven scenario, longevity should be the same.

 

Also, Vortech under rates the max impeller speed. But how much?

It is typical for the V7-YSI to be run @ 75,000 to 80,000rpm an 35psi+ (rated @ 65,000) on Drag Cars.

ProCharger impeller speed ratings are much higher, 80,000 rpm in a similar sized blower like the V2 and use the same type bearings.

Of corse SC Design and Materials play a big part.

 

I think the bearings 928 / Vortech use (abec 5 I believe) will be sufficient for a good while if you are not hammering on it day in and day out. And with the tolerance being tighter on the 7's and 9's I would be concearned with the generated heat possibly seizing them up. A little lose is not a 'bad' thing in my mind... Almost like an AK can go for a long time without a smidge of cleaning but if you try that with an AR the bolt will stop cycling due to carbon, dirt and grime building up on a tighter tolerance reciever.

Not sure if it works exactly the same in a SC but it makes a bit of sense.

 

The ABEC Rating is for Precision......... It's not a Matter of tight or Loose, although that is important.....

It's like The Space Shuttle vs. HomeDepot

The Higher the Precision, The Higher the Speed Rating. The Higher the Precision the Less Heat.

When Hal is Building your motor, do you what him to be Precise, or would you like him to tell you " ya, crank journal no1 was .0012", no2 was .0025", no3 was .0016" and no4 was .0023", ya, that's good enough....... No, you don't want that.

You want all journals the same. No more that +/- .0002" from his target. (for example .0014/.0018") target being .0016". And no more than .0002" from Journal to Journal.

 

oldman how long have you been on your setup? stock bearings right?

also here is what Carl from 928m said when i asked about the abec7-9 bearing

Be advised - they are using the ABEC rating (American Bearing Engineer's Committee) as evidence of quality - like the ABEC 7 bearings are better than the ABEC 5 bearings. That is not true.

ABEC 7 is a call out for dimensional specification, not quality. An ABEC 7 bearing is tighter than and ABEC 5 bearing. As such, it has less room to expand when heated.

If the engineers at Vortech called for an ABEC 5, I'd replace it with an ABEC 5 if I were you. Install too tight a bearing and watch it seize up when it gets hot!


Carl

Carl Fausett
Member SAE
www.928Motorsports.com and
www.SuperchargerUpgrades.com

 

That's kinda how I understood it... I am no expert at all but that's my understanding...

 

yea well long story short i will be running the 928m w upgraded seals from them and have them change out my old bearings and replace them with factories just to refresh them. will be pulling blower on sat and shipping it off to carl hopefully next week.