Cats and Cutouts

[Detroit_Bird]

Another Question for you guys-

I have a 95 T/A with single cat exhaust. I know in 96 GM switched to a dual cat system and picked up 10 horses (285 vs. 275). My car is due for some new pipes and due to Michigan not testing for emissions, I am able to remove my convertor if I so choose. I was wondering if y'all pick up any power by removing the cat on these cars, or if the stock cam profile needs backpressure to keep cyl pressures up. (Hence, I would lose power by removing it). The stock cam isn't going to stay forever, but I'll have to live with it until my I get enough money to finish my short block, and would like to prepare the exhaust for the new motor , I just don't want to lose power in the meantime.

- Now here's the other question- In place of the cat I was going to weld up a cutout. My exhaust is 3" from the y-pipe back, so I was wondering if I'm going to end up frying my passenger's feet or if there's still enough clearance there to avoid this. Kinda wondering if anyone has done this before and what results they've had with it.

[Black97]

Here are some views on this topic. There were others but I couldn't find them.

http://www.f-body.com/forum/showthre...ghlight=remove

[Detroit_Bird]

Thanks Black97- It sounds like removing the cat doesn't hurt performance, it just doesn't improve it either.

Next question is why was there a 10 horse hike when GM went to using dual cats in 96 (and 95 Cali cars)? Due to different Y-pipe config or what? I don't think anything else changed other than OBD2 and the cats that year.

[AmericanZ28]

There was a 10 Horsepower gain because the engine was now breathing easier by having a cat for each exhaust manifold instead of both of em fighting their way out through only one. Think of it this way, more air will flow through 2- 2" diameter cats instead of one 2 3/4" diameter cat. Make sense?