Post by §lôts® on Jul 8, 2005 11:38:32 GMT 7
There are several advantages associated with installing an aftermarket exhaust system: a more appealing look, better exhaust sound, a lighter ride, and more power are just a few of the key reasons why aftermarket exhausts are a must have. A dual system has the added benefit of helping the engine exhaust flow more freely, thereby reducing back pressure, which is inherent in most stock exhaust systems. Typically, adding a dual exhaust system will equate to a sizable increase in engine horsepower because the “breathing” capacity of the engine has been improved, leaving less exhaust gases in the engine at the end of each exhaust stroke. This, in theory, leaves more room for an extra intake of the air-fuel mixture, which normally equates to more horsepower.
The Borla Stainless Steel “True Dual” Cat-Back Exhaust System was chosen for it’s ease of installation and top notch fit and finish. The system is made from full aircraft-quality T304 stainless steel, and the welds are the best in the business. The ‘True Dual’ exhaust, designed with an H-pipe, is a split rear-exiting system with a 4 1/2-inch single round rolled edge angle cut tip at each exit. This system consists of dual 2 1/4-inch inlet pipes to a 2 1/4-inch H-pipe assembly. Exiting the H-pipe assembly are dual 2 1/4-inch pipes to a pair of 14-inch long by 4-inch diameter round mufflers. After the mufflers, a pair of 2 1/4-inch over axle pipes lead to a newly-designed X-flow muffler.
The installation went as advertised — very straight forward — and it took less than two hours to complete. The system mounts to the flange just after the catalytic converter and eliminates the factory Y-pipe. The complete system weighed in at only 51 pounds, compared with the factory exhaust system that weighs 62 pounds — 11 pounds were shed off the G’s waste line.
The gains over our baseline dyno run show horsepower gains (2 to 3 horsepower) at the rear wheels, factoring in an average of 15 percent drive train loss, this equates to 3.5 horsepower gain at the crank.
It also installed the Borla T304 Stainless Steel Header system that would replace the restrictive factory cast-iron exhaust manifolds. These absolute beauties were bound to turn the front half of the G’s exhaust system into a high-flowing power producer. The headers have a thick 3/8-inch header flange and come with Stage 8 locking header bolts, gaskets, and all other necessary installation hardware.
Backed by a million-mile warranty with promises for more horsepower and better gas mileage, these bad boys had our expectation set high — the Borla headers didn’t disappoint. A couple of quick runs on the dyno confirmed strong torque and horsepower gains exactly where you would want them, in the heart of the power band. Some 13 to 15 FtLbs of torque and 4 to 5 horsepower increase from as low as 3000 rpms all the way on up to the 6600 rpm redline — talk about a nice added kick in the pants. Unlike some performance gains which are only realized at the very top of the power band (redline), the Borla system gains put the power where you’ll use it in every day driving, in the midrange. Our only gripe was that the header flanges required some drilling to enlarge the flange bolt holes for a proper fit to the catalytic converters. We tried for several hours to get them to seat properly, and we even placed a call into Borla Technical support (we’re still waiting for a return call), but, ultimately, we just enlarged the holes 1/8-of-an-inch and our problem was solved.
The G now has an added punch when it revs past 3000 and pulls much harder and faster all the way up to the 6600 redline. The sound of the exhaust note is absolutely fantastic. The folks at Borla have done their homework on producing a more aggressive exhaust note over stock that’s not ever annoying or fatiguing.
The Borla Stainless Steel “True Dual” Cat-Back Exhaust System was chosen for it’s ease of installation and top notch fit and finish. The system is made from full aircraft-quality T304 stainless steel, and the welds are the best in the business. The ‘True Dual’ exhaust, designed with an H-pipe, is a split rear-exiting system with a 4 1/2-inch single round rolled edge angle cut tip at each exit. This system consists of dual 2 1/4-inch inlet pipes to a 2 1/4-inch H-pipe assembly. Exiting the H-pipe assembly are dual 2 1/4-inch pipes to a pair of 14-inch long by 4-inch diameter round mufflers. After the mufflers, a pair of 2 1/4-inch over axle pipes lead to a newly-designed X-flow muffler.
The installation went as advertised — very straight forward — and it took less than two hours to complete. The system mounts to the flange just after the catalytic converter and eliminates the factory Y-pipe. The complete system weighed in at only 51 pounds, compared with the factory exhaust system that weighs 62 pounds — 11 pounds were shed off the G’s waste line.
The gains over our baseline dyno run show horsepower gains (2 to 3 horsepower) at the rear wheels, factoring in an average of 15 percent drive train loss, this equates to 3.5 horsepower gain at the crank.
It also installed the Borla T304 Stainless Steel Header system that would replace the restrictive factory cast-iron exhaust manifolds. These absolute beauties were bound to turn the front half of the G’s exhaust system into a high-flowing power producer. The headers have a thick 3/8-inch header flange and come with Stage 8 locking header bolts, gaskets, and all other necessary installation hardware.
Backed by a million-mile warranty with promises for more horsepower and better gas mileage, these bad boys had our expectation set high — the Borla headers didn’t disappoint. A couple of quick runs on the dyno confirmed strong torque and horsepower gains exactly where you would want them, in the heart of the power band. Some 13 to 15 FtLbs of torque and 4 to 5 horsepower increase from as low as 3000 rpms all the way on up to the 6600 rpm redline — talk about a nice added kick in the pants. Unlike some performance gains which are only realized at the very top of the power band (redline), the Borla system gains put the power where you’ll use it in every day driving, in the midrange. Our only gripe was that the header flanges required some drilling to enlarge the flange bolt holes for a proper fit to the catalytic converters. We tried for several hours to get them to seat properly, and we even placed a call into Borla Technical support (we’re still waiting for a return call), but, ultimately, we just enlarged the holes 1/8-of-an-inch and our problem was solved.
The G now has an added punch when it revs past 3000 and pulls much harder and faster all the way up to the 6600 redline. The sound of the exhaust note is absolutely fantastic. The folks at Borla have done their homework on producing a more aggressive exhaust note over stock that’s not ever annoying or fatiguing.