"Over Spinning" a Blower?

Reply Subscribe

Thread Tools

Search this Thread

Oct 31, 2016 | 12:18 PM

derekd7987

Thread Starter

Pro

Joined: May 2014

Posts: 704

Likes: 47

From: South Carolina

"Over Spinning" a Blower?

So I've heard of people slightly spinning blowers over what the recommended max rpm is. My question is how much is ok? I have a V3-Si with a 3.8 pulley and am wanting to pulley down over the winter and hopefully be on e85 by the spring. Looks like the V3-Si has a max impeller speed of 52,000 rpm. I used the calculator on Vortech's website and here is what I came up with...

3.8 Pulley 46,184 at 6500 rpm

3.33 Pulley 52,702 at 6500 rpm

3.25 Pulley 54,000 at 6500 rpm

3.125 Pulley 56,160 at 6500 rpm

So my question is how much can you safely over spin it at the rpm you plan to shift at?

Last edited by derekd7987; Oct 31, 2016 at 12:24 PM.

Oct 31, 2016 | 02:08 PM

Quickshift_C5

Melting Slicks

Joined: Sep 2006

Posts: 2,728

Likes: 142

From: Iowa

I have the A&A Si V3 as well, but with a 3.4 pulley. I was told that's as low as I could go without over spinning the blower. It seems to match your research. The motor is set up and tuned to run out to 7k rpm, but I still shift at 6,500 to play it safe.

Last edited by Quickshift_C5; Oct 31, 2016 at 02:09 PM.

Oct 31, 2016 | 04:49 PM

SilverZ06NC

Racer

Joined: Mar 2009

Posts: 380

Likes: 5

From: Sanford NC

I had a 3.47 upper and the overdrive balancer shifting at 68-6900 and I got about 3,000 miles before the oil slinger disc came apart. I then upgraded to the YSI due the price to fix per Vortech after I sent it in. If you plan to turn it up go ahead and install a larger supercharger.

Nov 3, 2016 | 12:39 AM

derekd7987

Thread Starter

Pro

Joined: May 2014

Posts: 704

Likes: 47

From: South Carolina

i gotcha. appreciate the responses...

Nov 3, 2016 | 12:31 PM

robert miller

Team Owner

Joined: Jan 2007

Posts: 29,063

Likes: 1,839

From: cookeville tennessee

Quote:

Originally Posted by SilverZ06NC

The YSI loves it go with a 2.75 pulley on the top on the blower. Car should put out around 1,k to the wheels for you.. Robert

Nov 3, 2016 | 02:43 PM

SilverZ06NC

Racer

Joined: Mar 2009

Posts: 380

Likes: 5

From: Sanford NC

Quote:

Originally Posted by robert miller

The YSI loves it go with a 2.75 pulley on the top on the blower. Car should put out around 1,k to the wheels for you.. Robert

That was my pulley combo on the SI trim, not the YSI. Thanks
B wick

Nov 7, 2016 | 04:27 PM

C5Natie

Safety Car

Joined: Apr 2007

Posts: 3,582

Likes: 137

From: SoCal CA

The blower won't blow up or anything, it's just that at a certain point you're losing efficiency. You just start heating up the intake charge negating gains from the added psi. That being said the most I'll overspin a blower is 5k rpm or less passed its rated max impeller rpm.

Nov 7, 2016 | 10:02 PM

BLOWNBLUEZ06@RKT Performance

Supporting Vendor

Joined: Apr 2012

Posts: 2,673

Likes: 370

From: Forney TX

You'll notice that there is a lower RPM rating for the self-contained V3's over the engine-oil-fed units with all other things being equal. This means that the RPM limit was not determined by the impeller or it efficiency in this case.

I've seen many over spin the V3's and get away with it just fine. I've seen a handful over spin it and lose the oil slinger. A few of those instances, it happened almost immediately. If you decide to over spin it and it starts rattling like hell, let me know and I might be able to save you a ton of money on the repair. It's something that Vortech won't do for you.

Bret

__________________

Offering products from A&A Superchargers, East Coast Superchargers, Mechman Alternators, Mantic clutches, RPS clutches, Kooks Headers, Lakewood, LG, Brian Tooley Racing, Comp Cams, FAST, ARP, UPP Turbo systems, Wiseco, Callies, K1, MAST Motorsports, Haltech and many more. PM me for details.

Last edited by BLOWNBLUEZ06@RKT Performance; Nov 7, 2016 at 10:03 PM.