AcuraTLParts.com Blog

A sneak preview of a project we’ve been trying to save for our new site, but due to popular demand we had to leak a few pictures of the ATLP Quad Sport System for the 4G Acura TL.

Fresh of the assembly line, Ryan’s 2009 Acura TL fitted with a full header back ATLP Exhaust System. Limited quantities will be available to order online (FWD/Base Application). SH-AWD version in the works (we are seeking a SH-AWD TL near Orange County, CA).

Exhaust clips will be up next, although it’s going to be a quest to capture the true detail of this deep, throaty exhaust note on video.

Without further ado…

Pricing for the Cat-Back Exhaust starts at $1295 for the Base/FWD application.

To reserve yours, please e-mail us at hello@acuratlparts.com.

Dyno/R&D details to come.

Fundamentals

The J-series engine incorporated into the KB1 employs a very similar layout as the J-series engine native to the TL/TL-S, as well as the Accord V6 lineup. Having transverse engine layout is inherent with most Acura/Honda V6’s. Honda resorts to a primary catalyst for each side of the exhaust manifold, which is cast into the head itself. Essentially it’s an extremely compact 3-1 merge that takes place before it even exits through the head into the primary catalysts. Primarily tuned for optimal efficiency in emissions, as well as manufacturing ease, it leaves much to be desired on a performance level.

There are three components of these engines that are typically turned to for performance gains. The primary catalysts (or pre-cats), J-Pipe, and the Cat-back exhaust system. The pre-cats are fairly short in length and compact in shape thus much diversion from the factory design besides incorporating a higher flowing catalyst is fairly limited. Following the pre-cats the J-Pipe merges the two pulses from the separate banks together. Manipulating the factory J-Pipe in this case allows us more flexibility in adjusting the powerband to produce the desired increase in power and torque.

Factory Exhaust Setup

It’s easy to see the multiple restrictions the KB1 exhaust system inhibits over the 3G TL-S. This is in part due the choice of going with a semi-true dual setup for the RL. This produces a series of restrictions right from the beginning of the exhaust gas flow. The initial merge from bank 2 into the y-merge of the factory J-Pipe compromises performance greatly as friction to velocity ratio is much more critical in these sections of the exhaust system than it is further back towards the mufflers (Pinpoint A).

The factory setup involves many unnecessary power robbing components such as the merge into a single catalyst (3rd catalyst) to retain the manufacturing ease of using the same 3rd cat that can be found on all their transverse V6 power plants (Pinpoint B). Coming out of the 3rd catalyst it splits back to a true-dual setup. This again results in an unnecessary friction component as well as another source that will create internal turbulence (Pinpoint C).  At last but not least, the factory design incorporates yet another hiccup designed to reduce exterior exhaust note which is the addition of 2 resonators per exhaust stream and a reduction of ID tubing size at the exit of those resonators (Pinpoint D).

ATLP J-Pipe & Mid-Section 1

Our first plan was to make a part that replaces only the J-Pipe itself with the remainder of the exhaust system stock, but there is much left to be desired with only a J-Pipe replacement on a factory system that has this much restriction. A slightly more out-of-the box thinking landed us with the final decision to proceed with a J-Pipe & mid-section that allowed us to result in the most measurable power gains, enclosed an option to upgrade to hi-flow catalyst of the factory bottleneck, and also produce a more prominent exhaust note over the tinny, near non-existent note.

As proven by numerous dyno results and tests we have done to document various merge locations, we’ve shown that moving the merge further downstream up to a certain distance, consistently produced a higher torque and horsepower output throughout the whole powerband. In order to accommodate the J-Pipe to work with the factory cat-back exhaust system, while maintaining most useable power we designed a J-Pipe that extends back to the axle back mufflers flanges. This in term allows us to utilize a properly placed x-over merge to keep the velocities efficient throughout the entire length, which also means there will be a consistent power gain, not just found at wide-open throttle (WOT) that other parts claim.

The prototype design and R&D will be document here for clients to follow along. The first picture of many to come is only a non-functional mock up piece of the work in progress and is merely to show a rough idea of where this will be going. The final production piece will encompass mandrel bends, full 439 stainless steel construction, and will be a complete bolt-on replacement. Of course this will allow the KB1 to retain is factory look and drive-ability.

If you haven’t heard of CDT Audio before, you either haven’t been around the audio scene long enough, or the rock your living under must be really heavy. (really, really heavy!)

But seriously, when I first got a taste for the TL’s factory audio system, it was at the dealer when my salesman popped in the Demo DVD-Audio-CD (is it redundant to call it CD?). It was good, but not great. It didn’t take my breath away and although smooth, it just lacked the “kick” that you would expect from a luxury Acura, especially with a DVD medium delivering the music. I thought it was adequate enough for a stock system, but felt the need to flirt with an upgrade.

CDT Audio has been around for quiet a long time, and is especially well known in the audiophile arena. It’s not a mass-marketed product like Alpine, or Rocksford Fosgate, and is much more tuned towards SQ preferred listeners. SQ, standing for sound quality, rather than SPL which focuses on ear bleeding bass. Of course not only will this improve over the factory SQ, but it will also emphasize much on the SPL-less factory system that Elliot Scheiner has integrated into the TL. Although the system is a work of art by the renown producer, it still has it’s flaws and apparent let downs. Most notable is it’s lack of rich and clean lows, as well as crisp highs.

It only seems to live up to it’s hype when listening to DVD-Audio’s. And the ELS Demo CD. Go figure.

The sound engineering team at CDT Audio pinpointed this to the design flaw of the TL rear shelf structure, as have several members on the forum. The lack of a rigid shelf, and separated enclosures for each of the woofers in the rear deck results in a lack of pure and accurate bass. And once gains are turned up through the headunit, this is a weak point that is also amplified.

With a shallow woofer, and enclosure design, CDT has helped us design an “upgrade” that will compliment the remainder of the ELS stereo system, without going into a complete audio-overhaul project. We’re trying to accomplish the most, while modifying or adding the least possible. This means factory wiring, no amplifiers, low output converters, and all of that shenanigans.

Anyway, here are a few pictures of the first prototype.