What type of high flow cat would be the best for getting the most performance out of the car? also is it worth it if i can't afford the entire cat back?

 

Well there are procats which give good horsepower but they're not for ULEV vehicles so they won't last long because they're built to LEV spec.

If you want hi flow cats, get the Type-S cats, they are 600cell, the base TL is 900cell, so you should see maybe a few HP, only get the two primaries and don't worry about the third that should cost $800, it's been proven that removing the third cat does nothing.

 

cough cough, shameless plug I have a set of procats for sale $750 shipped, check the black market

as for the effectiveness of a high flow 3rd cat... with stock jpipe and stock exhaust the gains will be minimal

with jpipe and catback having the same dimater as the hi flow cat, you will have a free breathing exhaust and should see some nice gains throughout the powerband

 

haha actualy i just dished out over 500 dollar in mods (jpipe, cai, angel eyes, black out tail lights) in the last couple of days so im kinda broke rite now but ill get the cats eventually

 

If it's been proven that removing the third cat does nothing then why are people jumping all over getting test pipes???

 

^^ same questoin wht is the point of hte test pipe..wud removing the 3rd cat wid a aftermarket jpipe add power to the car. also is it true too much of a free flowing exhaust lowers tourque and power? or am i just making that up

 

Good question. I gutted mine and felt absolutely no difference. This is why I don't modify the TL. $2,000 down the road you've added 20hp. Not worth it IMO. For the same money it took to double my factory hp on my Buick, the TL would be putting down an extra 30hp.

 

Don't mean to hijack this thread....but if I was to install new J-Pipe + Magnaflows on my Type S. Would I make a difference?

 

Yes, the J-pipe is the only performance part in the TL that gains the most power, supercharger aside, and it's decently priced.

As far as the Magnaflows are concerned, that is contigent on the piping you're using. If you decide to remove the stock mufflers and replace them with magnaflow mufflers I doubt that will yield any gains. However if you upgrade the piping to a larger size and to something that is less restrictive that might yield gains.

There are, however, two full exhaust setups availible for the TL, the Excellerate performance exhaust, and another offered by ATLP, both of which, yield a modest horsepower increase.