Let me preface this, sorry for the noob question, I search and didnt see what I was looking for, so if there is a link please post

Hey guys, After all my searching and reading I cant seem to find the basic info about the naming and sizing conventions for a vortech system.

In the pic attached, I see 3 pulleys. On the radiator side is ribbed pulley #1.
On the otherside of the mounting plate directly opposite that ribbed pulley on the jackshaft? cogged pulley (#2). That pulley attaches directly to the blower is cogged pulley #3

Here's what I assume I know, correct me if i am wrong.

Since, the 2.87 pulley is ribbed and I assume thats #1 is what they call he supercharger pulley. The ribbed supercharger pulley is rated by diameter (3.12, 2.87 etc). NOW, on the vortech site, there's a cogged supercharger pulley rated at number of teeth.

How does the # of teeth compare to the diameter; ie, a 2.87 ribbed pulley makes the same boost as a 28 tooth cogged pulley?

Pulley#2 is assume is the jackshaft cog pulley which is connected to the supercharger ribbed pulley? Now Vortech offers differing # of teeth on the jackshaft cog pulley. Stock non-revup is a 32t. How does going up or down in tooth count affect boost.

When you see people talking about going to a 34t, does that mean supercharger cog pulley or jackshaft cog pulley; ie which number on the picture)?

I think my confusion comes in because in the picture theres pulley #3 attached to the supercharger. So i assume thats the supercharger pulley, yet its cogged, while I am ordering a 2.87 ribbed supercharger pulley (and that doesnt match up).

basically, FTW, what other pulley can i changed to make more boost in addition to the 2.87 ribbed supercharger pulley.

 

When everyone talks about the 34t cog pulley, it replaces #2 in your diagram. A 2.87 pulley with the 34t cog pulley if going to be a lot of boost . Probably about 15psi around 6600-6700 rpms. Do you have the the stock sc-trim blower or are you upgrading to a t-trim?

 

if you go up teeth on the #2 cog,youll get more boost, if you go down teeth on #3 cog you get more boost, if you put a smaller pulley 6 rib #1 u get more boost. on vortech's website under support, theres the impeller speed calculator, so you can try different combinations. you'll see you can easily exceed the max. rating impeller speed so you have to be careful with the stock blower.

 

i would upgrade to the 2.87 pulley on the #1 pulley. then just have a pro tuner tune it

then throw some nitrous on it

 

thanks a million guys. that clears it all up!!

i have a feeling, i'll have a pro tune it (whenever it all gets here) . problem is with n20 is that for the cost of that setup, I coulda went with a JWT setup from the start.


Anyone know the stock crank pulley diamter and the max impeller speed of the normal vortech V-2 blower?

 

stock crank dia. 5.75, and the blowers max is 53000

 

Vortechs can be very fast with some nitrous

 

How about you come to Cali and hook me up Jeremy!

 

Not meaning to thread jack, but when I put in all the specs of the stock setup with smaller pulley (5.75 crank dia, 3.12 jackshaft pulley, 32t cog jackshaft pulley, and 28t cog blower pulley) it shows that I am at 53,000 rpms for the blower . So does that mean I cannot run a smaller pulley for more boost? How are the revup guys getting away with a 2.87? Something has to be wrong here if the supercharger is only rated at 53,000 rpms for max impeller speed.

 

revups have a different cog setup, 34 tooth on jackshaft and32 tooth on blower. but even with that with a 2.87 were at 53768

 

Enter your crank pulley diameter in inches: 5.75
Enter your engine rpm at shift: 6900

Enter your supercharger cog pulley in teeth: 32

Enter your jack shaft cog pulley in teeth: 28

Enter your jack shaft serpentine pulley in diameter: 3.12

RPM = 40167.76

 

i think you got it backwards 28t for supercharger, 32t jackshaft pulley = 52464

 

^ this is the correct answer. So if I go to a 2.87 pulley I am surpassing the max impeller speed which is a bad thing right? How are others getting away with it? I already had to send my blower in for repair once, I don't want to have to do it again . But yet I want more boost .

 

^ are u sure its the correct crank pulley diameter ? ?

 

yes it can be, cant wait to see your quarter mile times after seeing you pull a couple 120 cars!! very cool...

 

i assume thats why you have to lower your rpm limiter with the small pulleys.

 

you can check with vortech on their upgrade program, for a different blower with higher impeller max.