Aftermarket Engines Bozeman MT
Accurate Auto Repair
621 E. Peach St.
Oil Change and Lube,AC and Heating Repair,Brake Repair,Cylinder and Block Repair,Emissions Testing,Mobile Auto Repair,Mufflers Repair,Truck Parts
Best Rate Repair and Towing
2107 Lea Avenue, # B
AC and Heating Repair,Truck Parts
Precision Automotive Repair
115 Commercial Drive, # B
Brake Repair,Electrical Repair,Mufflers Repair,Truck Parts
Napa Auto Parts of Belgrade
101 W Silverbow Ave
Auto Inn Garage
114 E Main Street
Engine Repair,Truck Parts
Carquest Auto Parts Store
425 N 7th Ave
Napa Auto Parts
514 W Aspen St
Auto Parts, Car Washes, Car Detailing
Premier FX Inc
430 Pronghorn Trail
Auto Glass Repair,Fabrication and Restoration,Truck Parts
Valley Truck and Equipment Repair
151 Andrea Drive
O'Reilly Auto Parts
103 W Mendenhall St
Data Provided By:
Data Provided By:
Build With Bolt-On Horsepower, But Proceed With Caution
Stores, catalogs and trade shows are loaded with companies selling parts that enthusiasts can bolt onto their cars to add underhood power.
By John Gunnell
Page 1 of 2
Whether the speed equipment is old school hardware or electronic in nature, you can be sure it is designed to turn automobile engines into more efficient air pumps.
“Because the engine really is an air pump, I tell my customers one of the biggest things they can do is bolt on a different exhaust system,” says Dick Casar of Done Rite Automotive Performance in (www.doneriteautomotive.com). Typically headers and dual exhausts will be installed on classic muscle cars, while newer cars will benefit from a 52-states-legal cat-back (catalytic converter back) exhaust system. Most cat-back systems are legal in all states.
Aftermarket headers are designed to give burnt gases exiting the engine a smoother flow route compared to factory-installed exhaust manifolds. Tight tuck models are available for cramped engine compartments. A long tube header kit with a two-inch diameter primary pipe and a pair of catalytic converters can run $1,000 to $2,000 (note: prices quoted in this article are ballpark prices at the counter with your markup).
Brand name systems are usually designed for direct fits on specific cars and can add 8 to 10 hp. Stainless steel hardware will eliminate rust, but mild steel hardware is stronger; your choice. Look for kits that have exhaust manifold studs with hexes on the end for easy installation with an Allen wrench. Before ordering your studs, double check how long you need them to be.
For about $400-$500 a performance style free-flowing exhaust system will include fat mandrel-bent pipes (usually 2-1/2-in. diameter) and low-restriction type mufflers for an increase of 15 to 20 hp. Due to emissions regulations, modern cars need to go with the cat-back option, which will give boosts in the 11-15 hp range for $1,200 to $1,500.
The critical fuel/air mixture that feeds the “air pump” its proper diet is another area where improvements can be made today, says Casar. “On your older carbureted cars, look for gains in the eight horsepower range after adding an aftermarket performance carburetor that will flow 650 cubic feet of air per minute through the engine. Or you can add bigger jets and get the carburetor pumping up to 750 cfm of air for roughly a 10-hp gain.”
According to Ed Casar Dick’s son and partner at Done Rite Automotive Performance carburetor companies haven’t been sleeping. Recently, they came out with models that incorporate new ways to atomize fuel. “They look the same as the old double pumper, but lasers are used to drill smaller holes and the manufacturers also have more surface control today.”
Ed continues, “Thanks to the air/fuel meters we have now, we can take a carbureted car, put it on our Super Flow dyno and tune the thing t...
Click here to read more from Engine Builder