alexpapas90

So I think I need to buy new Cats... feeling throttle response lag and getting a sulfer/egg smell from exhaust... no engine codes though.

Now I already replaced the midpipe and resonator with with a DynoBullet pipe.. I freaking love the sound, kinda sounds like a g35 and I get NO RASP!

Now I'm thinking i should replace the cats with high-flow cats and a new j-pipe.

I'm going to keep the stock exhaust and Dynobullet... which high-flow cats and j-pipe combo do you all think will keep rasp to a minimum? Any ideas?

horseshoez

iTrader: (2)

Don't rule out the upstream O2 sensors; they often get lazy but don't throw any codes.

alexpapas90

Forgot to mention: I replaced both upper 02's (Denso)... seems like low end tourqe increased then after 30mins of driving the lag and low end tourqe loss returned. Thought it was the new sensors, reverted back to OEM and it did the same thing after 30-40mins... also disconnected battery to reset ECU each time. Strange as Hell! Both banks are also running leanish (longs at 10%) and already replaced EGR valve, PVC valve, spark plugs, and intake Smoke Test showed no intake leaks... valve adjustment done 8k ago as well.

1black_seven

iTrader: (2)

I really like the RV6-P j-pipe and HFPC combo. Huge bitch to install tho

alexpapas90

Yeah I was leaning towards this configuration. Do I have to remove the driver side axle to remove the rear cat? Or were you able to pull it out directly from under the car?

alexpapas90

So I'm sold on the RV6 HFPC..

Now I'm stuck between the XLR8 V2 and ATLP V2-R... which one will have less RASP? That's what this comes down... anyone have an idea?

1black_seven

iTrader: (2)

I don't remember what I did the first time, I think the sub frame had the be dropped in order to install the rear cat.
2nd time around I rebuilt the motor so it was "easy", I just pulled the block out and installed them.

Acura TL Builder

90foxnotch

^He's got the good version...Manual, no cooler needed

alexpapas90

Remove subframe! Yikes! Well hopefully that wont be required.

alexpapas90

And yes I have a 6 speed manual, so the trans isnt the issue here 😁

losiglow

iTrader: (1)

No, the subframe doesn't need to be dropped to install the rear cat. You'll have to remove the sway bar and the aluminum heat shields around the stock cat, which is a bit of a pain. I believe there are four bolts which are a bit difficult to get to but by no means impossible. The catalytic converter is held on to the block by four bolts, as well as three bolts on the jpipe. Then it's a matter of getting it out of the back of the engine which again, can be tricky but not super bad IMO. I've done it on a 3G and 4G. You'll want to take the fuel/air O2 sensor off before trying to jimmy it out.

But yes, RV6 high-flow cats (the only option really) and either an RV6 or XLR8 jpipe. I had the hfpc's and RV6 jpipe on my 3G and loved it. Excellent upgrade to both sound and power.

tenacious tl

iTrader: (1)

I go from the top when removing the cats. For the front, you just have to remove one of the radiator fans. For the rear, you need to remove the strut tower brace and rear coil packs. You also have to remove the heat shield from the cat while it's down there, but it's not too bad. I budget 4-5 hours to remove and reinstall cats. I went the cheap way of gutting the stock cats and installing defoulers for the downstream O2 sensors.

alexpapas90

Thank you for explaining. Do you have to reinstall the heat shield on the HFPC's? or did you just install it without the heat shield?

Do you or anyone else know which jpipe produces less rasp... between the RV6, ATLP V2-R, and XLR8? any ideas?

90foxnotch

I did not replace the heat shields on my PCDs, I don't think anyone does. Your rasp will come if you delete the 3rd cat and modify the catback. If you decide to do a long tube jpipe that deletes the 3rd cat I would suggest buying a resonator and it will help. Search on the forum and all your answers will be found about any exhaust related items

Scottwax

Absolutely zero rasp with the XLR8 v2. In fact, I barely noticed any change in sound with mine.

ExcelerateRep

We also recommend the XLR8 V2 Jpipe!

If you are trying to combat rasp you can add another resonator to the mix, or remove the existing one and weld in an aftermarket option. We have had good luck with Vibrant's resonators for this (even on cars with PCDs and V2 Jpipes), so that is what I would recommend! The build quality is nice and they work great.

Feel free to send me a PM if you need help getting setup! Rasp should not be bad with the stock exhaust and HFPCs however!

Happy modding!

ExcelerateRep

I was going to edit the original post but missed the 15 minute window! I did want to clarify something quick though:

While a resonator isn't designed specifically to eliminate rasp, it does help! These cars tend to become raspy due to the design of the exhaust system, and the placement of pre-cats in particular. When you install the PCDs you lose the restriction of the OEM cats, which also act like a mufflers. Changing the pre-cats effect exhaust flow, which in turn changes sound.

Hope that helps!

DerrickW

To answer your original question (which j-pipe to go with), I put in the XLR8 V2 a little over a year ago & have nothing but good things to say about it. The design is excellent, welds were sturdy and extremely well done, it slid into place and fit like a glove with zero effort. My config was : stock/original precats > Magnaflow resonator > deleted mid-muffler > stock mufflers. Adding the XLR8 made the sound simply awesome. Nice and low and rumbley down low in the rev range, quiet but muscular sounding in the mid-range. It does get a little raspy up top, but I don't rev to nor drive around at 5,000+ rpm all that often so to me its a wholly acceptable trade off.

UncleDave

My experience in this matter after a few different versions, has resulted in total satisfaction with the following setup:

HFCD on engine, RV6 J Pipe Long pipe version, Comp tech cat back.

This has produced the most beautiful tone when running, quiet under cruise, nice sound and very throaty when accel hard, and overall a beautiful crisp sound that is perfect. Not too loud, not too quiet, but overall a great running setup.

Produces great power, very torquey ( prob the J37 Swap in my J32 block.)

Overall the best IMO setup I have seen or heard so far.
Dave