sciff5

iTrader: (1)

Around How much hp am I going to lose if I have a serious h/c 347 with true dual 3" all the way back?

And will the high flow cats even be enough for me to pass emissions in MA with a TREX (or even more agressive custom grind) cam and ported ls6 heads??

A-Dub

iTrader: (6)

I just put magnaflow 59959s on my car, bolt ons stg 2.5 5.3s and a 224 cam. In houston, my car won't have to pass sniff, just a scan and visuals. In my case, it will pass. Not sure about MA, if you have to pass sniff they may not just because a large cam like that will be very inefficient at low rpms....maybe some creative tuning would help it

TheBlurLS1

iTrader: (8)

Call up EAD Performance, they are a vendor for the high-flow magnaflow cats (59959's mentioned above). Tim should be able to get you a good deal on a set.

GR33N GoblinM6

iTrader: (14)

are these 59959's considered OBDII compliant? Here in utah.. they said we have to use this... can be aftermarket, and dont have to be in stock location.. which is good.. but does anyone know if these are considered this? If not looks like i will have to get the other carsound cats.

radkon

iTrader: (2)

It'll probably pass visual, as long as they just scan and you're not throwing codes you'll be ok but there's no way that cam will pass a sniffer.