After removing and replacing my opti (screws fell out of rotor) I found that the ignition module was bad. I don't ever want to have to pull that opti again!

While it was apart I installed me new 2.5 compressor puley and I am seeing a consistent 5-6 pounds now. I think this is good considering I am pushing a 383 through an FMIC. I am trying to decide whether to go to a 7" crank pulley or not. It is pulling hard and strong and consistent all the way to my 6400 pill. I know this would be overspinning my S-Trim, but I'm looking to see what others think.

Chas

 

Chas,

Assuming you have a 6.66 crank pulley currently, you would be at 57,668 on the blower or about 15% over redline. A 7" CP would put you at 60,600/21%.

Not sure when you would run into comp. surge/choke. Maybe others could chime in.

Boost would come in sooner so more mid-range/torque. But efficiency will fall off the map (<%65) at 5275 eng.rpm yielding higher IAT with greater chance of compressor damage and detonation. Also, the lower the compressor eff. the more engine horsepower it will take to drive it. So at some point less than 65% efficiency you are going to hurt the blower and or engine. Vortech does state that the S-trim will operate below 65% efficiency though.

http://www.vortechsuperchargers.com/maps/s-trim_map.gif

-Scott.

 

Thanks alot for the response Scott. I am actually running a 6" crank pulley. It does look as though the T-trim is a deal that will be coming through, so I am not going to chance hurting the S-trim in hopes of selling it to recoup some of the output.

I really appreciate the response though.

Chas