HPM Welded Turbo Mufflers 5-1/2″ x 11″ Oval Body
Double-wrapped welded aluminized mufflers with two baffles and cores (most configurations). The double wrapped shell helps to give a quieter sound than single-wrapped welded turbos. Mufflers are reversible. These have a 5-1/2″ x 11″ oval body and are available in 14″ or 18″ body lengths. These are our quietest, especially the 18″, performance muffler, and have a nice flow rate for a turbo muffler. The # 1142 was flow tested at 222 cfm at 10″ of water.
sound clip is on a 2001 GM Silverado 5.3L regular cab long box pickup truck.
HPM Welded Turbo Mufflers 4″ x 9″ Oval Body
Smaller 4″ x 9″ body size where space is a concern. Aluminized mufflers have a double-wrapped shell, 409 s/s are single wrapped, and made entirely of 400 series stainless steel. Both aluminized and 409 s/s contain 2 perforated 409 s/s 2-1/4″ cores and s/s inner baffles for good exhaust flow and a powerful sound. These mufflers are fully welded and are reversible. Flow tested at 10″ of water. An IMCO # T-906 flowed at 157 cfm, and a # T-904 at 156 cfm at 10″ of water for comparison.
| 409 S/S # | Aluminized # | Inlet/Outlet | Body | OAL | Flow |
| 4491112 | 491112 | 2″ single offset | 14″ | 19″ | |
| 4491122 | 491122 | 2-1/4″ single offset | 14″ | 19″ | 190 cfm |
| 4491132 | 491132 | 2-1/2″ single offset | 14″ | 19″ | |
| 4491212 | 491212 | 2″ double offset | 14″ | 19″ | |
| 4491222 | 491222 | 2-1/4″ double offset | 14″ | 19″ | 185 cfm |
| 4491232 | 491232 | 2-1/2″ double offset | 14″ | 19″ |