There was a charity dyno event today. Looks like tq dropped quite a bit since adding the prochamber. Here is the before and after prochambers.
Engine temp could have played a factor in the peak hp and tq numbers. My hp went up by 2-3 but tq dropped a by 2-4.

The vid didn't come out well. I was too far back and the too much background noise
http://www.youtube.com/watch?v=Np10PVdII1s

 

yea, I would guess that a change of just a few hp and tq could most likely be attributed to change in the air & temperature rather than the exhaust itself, if the before & after were on different days. Could be either I guess!

 

Another factor could be, that once you remove the cats along with running a straight thru mid-pipe. You also end up losing backpressure, which directly affects low and mid-range torque.


Just my $.02

 

I think you are right. It does feel like I lost power in the lower RPM ranges, but once the car gets to about 3000 RPMs, it feels faster.

 

That was my main reason for getting the MAC Prochamber w/high-flow cats. This way, I still have enough backpressure to avoid losing any low/mid range torque.

 

That's odd.. I had before/after dyno runs and she gained roughly 7rwhp & 10rwtq after installing the off-road prochamber (same dyno).

 

I am looking at some high flow cats. Many choices that I need to do some research on.

 

I called two shops today asking about CATs. One shop quoted me $189 ea. But they couldn't do the install since they do smog checks. Another quoted me $425 with install. Staying O/R looks better and better.

 

If price is your concern, then you may want to consider www.pypesexhaust.com They have what's called mini cats, which are much less expensive than the quotes you got from those shops.

 

I have considered the mini cats, but would they fit? It says 3" and the exhaust is 2.5"? Also might be hard to find a place to install them here in CA.

 

I don't see why they wouldn't. As another TMS has already fabricated them to fit onto a MAC O/R Prochamber. I just can't remember which thread it was listed under. But I do know, it was somewhere in the 05-09 GT Performance Mods forum.

 

He posted in my thread. I think this is the one you are talking about.. Here is a link to some different cats you can choose from http://www.ninosport.com/Mustang/Cat...4Pa38Ta38Oc350

http://forums.bradbarnett.net/showthread.php?t=474088

 

I think most muffler/exhaust shops will not install aftermarket cats because of legal issues. Two of the exhaust shops I called said the they can sell me cats, but can't install them.

 

I have also considered these. http://www.pysales.com/iwwida.pvx?;i...0%201?comp=ppe
Richard over at Radmustangs.com can get me these for 194.00 for the pair.