Well I did the Mac single cat conversion and I am very pleased. The car pulls so so much harder on the top end it is unbelievable. However, is it possible that I lost some of my low end torquieness?? I am wondering why it seems that my powerband got shifted up into the higher rpms and I lost some in the low rpms. I am thinking maybe I am feeling this way is not because I lost any in the low end, but because I gained so much it made the low rpms seem like I lost some. I reccomend this setup to everyone, plug access is great, just changed my plug wires in less than an hour.

 

Backpressure maybe?

 

If everything is hooked up correctly, you will gain TQ and HP EVERYWHERE.

Check out this link of a stock LT1 dyno vs what I dynoed with your same setup.

Click Here

Backpressure is bad. It does not gain you low end TQ. It's an old myth.

Dan

 

When I dynoed before and after headders, I gained more in the top end and mid range. I only got a few down low. So that's probably why it "seems" like you lost some, just because you didn't gain as much on your low end. When I got a tune from Ion, it flattened out my torque curve again.

 

I was also thinking about going to the 94/95 style headers with an OR Y pipe.

Did all of your AIR and EGR fittings mate up properly ?

Also did you have to fab up any exhaust extensions to connect to your cat back ?

 

you know what when i first put my long tubes on i would have swore my car was less torquey down low,but a trip to the dyno said the opposite, maybe i think the different sound and reduced backpressure might make it feel like that but i assure you you picked up power throughout the entire power band.