Wheels-up launches like this...
Wheels-up launches like this are common for Ward Alston's G/FI NHRA Stock Eliminator '88 GT. Before we installed Direct Natural Airflow Performance Mufflers' Gen II Race Series mufflers, this 'Stang had not worn any sort of exhaust cans since 1997, when it was retired from street duty and transformed into a full-on race car. On the dragstrip, Ward's car covers the first sixty feet in the low 1.60s without mufflers. Unfortunately, we were unable to get back to the track before this report was written, so 60-foot data with Direct Natural Airflow's 3-inch Gen III Race Series mufflers and Fast Intentions crossover exhaust system is not available. Based on the small but promising torque improvement we saw on the dyno, however, we suspect Ward might notice a slight improvement in the car's short time when he finally gets the opportunity to launch with his 'Stang's exhaust corked up.
Some things are just meant to happen, only when the time is right. That's truly the case when it comes to a few ideas we've had for this section of the magazine. Tech Inspection is primarily about installing and evaluating the latest in fairly basic, bolt-on "cool" for '79-'06 Mustangs. Sure, we occasionally revisit some of the street-only, and, street/strip technology that we may have reported on in the past, especially if that technology has been updated or improved in some way, but we hardly ever present our readers with details about 'Stang parts that are made specifically with hardcore, race-only Mustangs in mind. Both NMRA, and Fun Ford Weekend racers have checked us about this neglect on various occasions, but thanks to a series of timely events, we're able to dedicate this month's report on a set of mufflers and an exhaust system that scream one thing, and one thing only: "Let's go racin', boys!"
Call it the stars aligning properly or whatever you want, but, it's not often that we speak with a racer in need, on the same day we receive media information about a new part--and the part is exactly what the needy racer called us about. That's how it went down when Ward Alston of Mission Hills, California, called us for guidance on a set of race mufflers for his NHRA G/FI Stock Eliminator '88 Mustang GT. Like most cars that compete in the NHRA's Stock and Super Stock (think, NMRA's Factory Stock, Pure Street and Hot Street run in bracket format) classes, Ward's `Stang has always been raced with open headers (actually, the car, once a 160,000-mile daily driver, hasn't worn mufflers since it became a race car, back in 1997). However, due to noise-level restrictions and a mufflers only rules at Irwindale Raceway, Ward was in need of a good set of cans that will suppress the cackle of the basically stock 302 under his hood, without restricting the flow of exiting exhaust gas and hurting the GT's performance on the track.
Direct Natural Airflow Performance Mufflers is a division of Technoflange, Inc. of Ajax, Ontario, Canada. The company was not on our radar prior to receiving its press release and Web link. But after checking out DNA's 3-inch, stainless-steel, Gen II Race Series mufflers [PN 1012-2; $179.99] on the Web site, and in speaking with DNA's Vice President of Sales and Marketing Randall Perks about the idea we had for this story (to take a competitive, naturally aspirated race car that has never used mufflers and see what kind of gains--or losses--there are on the dyno and on the track, as well as checking the audible differences after mufflers have been installed), we found out quite a bit about DNA mufflers (the company offers a variety of patented mufflers for race, street, and truck-applications as well) and were anxious to give them a tryout.
The Gen II Race Series muffler's internal design is unlike any other race or performance muffler we've seen. The muffler incorporates a network of strategically placed "sound diffusers" that spiral through the can from inlet to outlet, and allow exhaust gases to pass through the muffler virtually unrestricted. Sound diffusers also deflect sound, and actually determine the decibel levels a muffler produces. The longer the muffler (and more diffusers there are inside), the lower the noise level.
Ward wanted a good, 3-inch exhaust system for his Mustang that can be easily bolted-on or taken off in the pits, so we called on the services of Danny Akre, Tony Meyerson and Mike Mendrek of Fast Intentions [www.fastintentions.com; (818) 882-2788]. Fast Intentions is an upstart, performance-exhaust shop based in Northridge, California, that specializes in everything from custom race headers (the guys were in the process of fabbing up a set of stepped tubes for a vintage '70 Boss 302 SCCA road-race `Stang when we arrived, and they've even made tricked-out headers for customers who are lucky enough to own Ford's ultimate super car, the GT) to high-flow exhaust systems for all types of high-performance `Stang applications, and the super-clean, mandrel-bent, 3-inch, fully bolt-on exhaust tubing they set up is a total work of art that fits like a glove under the backside of Ward's '88 stocker.
Addressing our noise concerns, we've got to say that the DNA Gen II Race Series mufflers do a great job of knocking down the decibels, without sacrificing anything when it comes to a strong, racecar "growl." While we're pretty much used to the sounds of the various mufflers used by racers in both, all-Ford-drag-racing sanctions, these new mufflers are uniquely toned, and make for a cool addition to the market. On the performance side, we strapped Ward's Mustang to the Clayton chassis dyno at B&D Racing in Canoga Park, California, to find out how the stock 302 would respond in both modes...with, and without exhaust. The results, as you'll find when you read on, were quite interesting.
 Mike Mendrek welding the crossover...  Mike Mendrek welding the crossover tube in the exhaust system |  Mike Mendrek of Fast Intentions...  Mike Mendrek of Fast Intentions removes the foot-long pieces of open, 3-inch straight tube that were bolted to the collectors of the small, 1 5/8 MAC long-tube headers on Ward's `Stang (installing a set of true, stepped, race headers will also do Ward's car a lot of good). The plan is for the Fast Intentions crew to install its own custom-bent exhaust pipes (including a balance tube between the two sides) that will run from the collectors all the way to the rear end housing, with turndowns off the outlet of each muffler. Fast Intentions uses a special, 3/8-inch thick, laser-cut, collector flanges for applications like this, as they've found that stock flanges are prone to warping under the excessive heat of the exhaust. |  DNA is the latest player in...  DNA is the latest player in the race-muffler game, and we must say we're impressed with the quality, sound and performance of the Gen II Race Series cans we tested [PN 1012-2; $179.99]. These 5 -inch (wide), 21-inch (long) mufflers carry a 5-year, limited warranty and are made with lightweight B2 stainless steel. All DNA race-series mufflers include custom brackets at each inlet, for additional support, and vent tubes that dissipate high exhaust temperatures. Venting heat away from race mufflers can improve their efficiency and durability over time. |
 This is a close look at the...  This is a close look at the unique "sound diffusers" found on inside the Gen II Race Series muffler. Sound diffusers send exhaust gasses through the muffler without any restriction, while still maintaining a deep, throaty sound when the revs climb. |  Mike uses a Ercolina mandrel...  Mike uses a Ercolina mandrel bender to manipulate the tubes used for Ward's and other exhaust systems created by Fast Intentions. Mandrel bending has become the norm for high-performance exhaust production, as the process allows exhaust fabricators to put literally any amount of bend or rotation into small-, or large-diameter tubing, without crushing the tube or compromising a flow path. |  Fast Intentions' Tony Meyerson...  Fast Intentions' Tony Meyerson TIG welds a custom turndown on the outlet of a DNA Gen II muffler. |
 Mike welds a 3-inch balance...  Mike welds a 3-inch balance tube into the new exhaust system. The crossover equalizes the exhaust flow between the left-, and right-side tubes. Balanced exhaust flow is very important for a naturally aspirated, stock 5.0 like Ward's, as it helps improve low-end torque. |  As we said earlier, Fast Intentions...  As we said earlier, Fast Intentions put together a real masterpiece. The DNA mufflers have been TIG-welded to an H-style exhaust system featuring 13-gauge, aluminized, 3-inch diameter tubing. The system fits like an OEM unit under Ward's '88 Mustang, so there are absolutely no clearance (with trailer, ground, etc) issues whatsoever. |  While Ward (for now) intends...  While Ward (for now) intends to use his new DNA Performance Muffler/Fast Intentions exhaust setup primarily for keeping the noise down when moving the car around in his neighborhood (loading, unloading, etc) and when he goes out for eighth-mile test laps for 60-foot data. However, the runs we made on the Clayton chassis dyno at B&D Racing really opened his eyes to the improved performance (especially on the torque side) that his 'Stang might really gain if he dials-in a good tune with the exhaust system installed. Ward also learned about the importance of good air/fuel, and why investing in a wideband 02 sensor for his FAST engine-management system would be a good idea. We did not do any tuning whatsoever during our dyno session (our project was done with Ward just a few days away from competing in an NHRA points race and we did not want to disturb the engine's race program), and Ward's `Stang basically runs with a tune that has not been touched in five years (NHRA's Stock Eliminator competition can be thought of as bracket racing at its highest level, so consistency is critical for success). On the dyno, first with open exhaust, the stock 5.0 laid down a stout 272.9 horsepower and 284.2 lb-ft of torque at the rear wheels. We also noticed that the 302's air/fuel ratio stayed around 12.7-12.9 through the sweet spot of the rpm range, which is great for the stock-everything configuration of the engine. We then bolted-up the new, 3-inch exhaust pipes and DNA Gen II Race Series mufflers and tested again. In corked-up trim, the stock Mustang lost a bit of horsepower (265.9 hp) but gained rear-wheel torque, as we predicted it would, with 288.3 lb-ft. The addition of an exhaust system did richen the air/fuel mixture considerably (10.0), but we feel that a more-optimal ratio, and even more torque, can certainly be achieved with dyno tuning. |