joelh86

i have a fujitsubo catback exhaust with injen CAI...
i was wondering how many horsepower increased from installing both..

PixelHarmony

You'll probably be running 210-215 at the fly. The exhuast doesn't really do much for you as far as peak HP.

rmpage

I have the Fuji exhaust too. It's awesome.

With just a catback you're probably only gaining 1-2bhp however.

The intake/exhaust tract as you know is a complete system. When you replace the catback, you are changing the very end of that system, but nothing else. Upstream, you still have the OE headers (which aren't that bad as far as OE headers go) and a catalytic converter that is restrictive. The engine will still have to push exhaust gases through both of these areas, so it won't matter much if you clear up restrictions downstream of them. A catback upgrade, especially on a car like the TSX which already has a pretty good OE exhaust system, doesn't do much.

Personally I suspect that the cat is the most restrictive piece of the whole system so I'm replacing mine with a Magnaflow this Thursday. I'll probably have a test pipe made just for shits and giggles while I'm down there, too.

To answer your question I would say that the CAI is giving you 99% of the power that you now feel, and if you want any respectable gains off the Fujitsubo you'll need to widen the tract upstream as well.

RMATIC09

i have the same setup, looking to get hondata soon and headers eventually to complete everything.

cmf

Be sure to write up how that Magnaflow cat works out. Wonder how much that will help, vs running a straight pipe.

rmpage

Well I'm having the Hondata intake spacer and Comptech header put in at the same time so I'm going to have to make sure to determine what gains are attributable to which upgrade. What I'm going to have them do is put the spacer and header on, dyno it, then put in the cat and dyno again.

Only question is if their dyno will be online or not. They've been putting in an AWD dyno recently and I'm not sure if it's done or not yet. Even if I have to rely on my butt dyno I'll have pics.

cmf

Any updates with the magnaflow cat? I am really curious as to what you gained or lost from installing it. You should have a pretty free flowing exhaust now, correct (I/H/E with hiflow cat)?

rmpage

Ah yeah, I was going to post a thread about this next week sometime when I got more news.

I didn't get it tested with the Magnaflow yet. There's a potential problem. The downstream O2 sensor plugs into the middle of the OE cat and plunges deep into the catalyst itself. On the Magnaflow, the downstream bung is right after the catalyst and protrudes into the pipe - and the exhaust gases. This suggests that there will be some lights when I run the vehicle with the Magnaflow in it, because it may be fully exposed to the gases rather than shielded by the catalyst material. Also, the OE cat is damn huge - probably triple the internal volume if the Magnaflow, if not more. The TSX is a ULEV, so the OE cat must do some serious cleaning. I'm not sure if the Magnaflow will even work with it, despite the model I selected being an OBD2/ULEV converter.

For this reason I told them to hold off welding the Magnaflow in, and instead fabricate a set of flanges so that I can bolt it in and out at my leisure (in case it doesn't scrub the gases enough).

I had them cut the proprietary Acura flange off the OE header and use it for the hot side of the cat (the cold side is a standard 3 bolt of course) so that I can swap the Magnaflow in and out at my leisure.

I hope to get back there next week and bolt the sucker in, lights or no lights. If I get lights, well, I have a few other things in mind.

cmf

^^ Sweet, can't wait to see the outcome. Hopefully it's no lights.

JTso

iTrader: (2)

You should be fine as long as the secondary O2 sensor is behind the catalyst material, as the ECU is looking for a change of sensor output.