I think I've had enough of this VR4.

[Dirk Diggler]

Man O Man, Some people have all the luck, not me! I purchased my VR4 last year and could not get much over 8psi. Power difference was not much compared to my sn2000. I had a 6 rib pulley system and was told I needed to upgrade to an 8 rib. I sold it, then a few months ago, purchase another one. I also got the 8 rib setup. Well, now, I only get 10psi out of the unit. Changed injectors, got it runnig ok. But to get a consistant 10 psi, I had to get 64inch/lbs on teh ball drive. Needless to say, the balls went bad. Thankfully, I purchased a Maxi pack of the 1 1/16 balls from a local machine shop:D 20 balls for the price of one set from paradise. Anywho, When I had 52inch/lbs on the ball drive, boost would build to 9-10 psi, then fall to 5-6ish. I was told this was belt slippage. But I"m running an 8 rib 7.5 crank and a 3.75 supercharger pulley WTHeck? No matter how tight, boost still falls! But when I put extra torque on the ball drive, it holds consistant boost of 10 almost 11psi.

Any ideas?

I've had enough of this VR4 crap

[speedytang]

What are you using for fluid. I am with you that your slippage is internal not the belt because when you increase the race pressure it holds boost. The only thing left is that the pressure is not staying constant when it is spinning. Could the race be moving down when the balls start to rotate at speed. What is being used for shims could the shim be moving down taking pressure off then when you let off the pressure the shim moves back up. Could it be a BOV that is not holding. If your using a BOV plug the holes for now then drive and see if it holds the boost. Other than that the last thing is you blowing past the rings each time your under hard boost. Sorry shooting in the air big time since I am not seeing it myself. Time to get a used Novi 1000-2000 and at least you can pulley to 15psi and take the ball drive out of the loop.

[speedytang]

P.S. What are the balls used for in a machine shop. I would like to be able to purchase some that way myself.LOL

[Dirk Diggler]

I can give you the number for the shop. Might cost you some extra $ for shipping. If we have to, you can send me the $ and I"ll send them to ya if need be. PM me with your phone no. I'll give you a call, would LOVE To talk to you regarding this issue with my VR4 and maybe help you get hooked up with the balls.

I'm running Ford type F fluid. I considered using the Trick Shift, but may hold off for a while. I"m not running a BOV as of yet. Shims are the ones Craig supplied. I made two extra holes via the machine shop where the races drop into the case, no excessive wear in them After adding the 30lb injectors, I changed the constant in the chip to 30lb inj. The car was still running lean I set the constant to 21 and it ran fine @ WOT. Very rich @ idle. I would LOVE to get a novi 2000, but they don't make them for my car... 91 Z 28 camaro.

I Think it may be time to sell the VR4...AGAIN:( Just have had no luck with this ting