I gotta say cutout, but some of the local car club guys think I'm an idiot, even saying a muffler outflowed a cutout by 118% ( ). Then again they do mostly drive Mustangs...

Anyway, what does everyone else think?

 

A cut out. There is no way that a muffler can out flow a cut out.

 

Agreed. Cutouts make more power, but a good catback (i.e. SLP 2otl, hint hint) will only cost you 2-3rwhp over a cutout. Sounds better IMHO, too. But yeah, those Mustang guys sure are confused..

 

I gained 8rwhp with my custom 2" Lowe's Cutout with my Edelbrock headers, !cat, and ultraflo muffler. But when I switched to my Hooker LT, custom Y-pipe, 2OTL, and flowtech 3" cutout, I only gained 2rwhp with the cutout open on the dyno.

 

Not that you asked, but I believe a cutout lessens your torque a bit...

 

Don't know for sure, but several dyno sheets showing the effects of cutouts don't show a loss of torque but the addition of 1-2 ft/lbs (all of them I've seen). Even then, losing a few ft/lbs that wouldn't have gone to the ground anyways shouldn't be that bad. I didn't feel any significant loss of torque (butt dyno), but I know my car feels better up top now.

 

Actually I think thats dependant on where you place the cut-out. It matters...

 

I hear all these people talk about losing torque when you open a cut out.....even though i've never personally seen a dyno sheet that shows a loss. Every dyno sheet i've ever seen has shown an increase in torque.

 

Could it be that your car SOUNDS like a monster at 2k rpms so you expect it to haul more *** but it just performs the same. I don't think you lose torque, it's all the uncertainty of the butt'o'meter. But i don't like cutouts anyways, definitly not on the street at least.

-Brent

 

The biggest I would go on a cutout is 2" right before the axle.

Bigger than that and you lose bottom end.

I used to have one and some of my friends have them.

 

Just get a Borla, and have the option of both.

 

My point being is that once you get to a certain point of relieving backpressure, you eventually lose bottom-end or torque. But you will still gain in the top end. Length of a tube and backpressure are big factors in torque.