Free Horsepower
01-27-2005, 02:50 AM
#1
2nd Gear Member
Thread Starter
Join Date: Nov 2004
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Posts: 435
Free Horsepower
MM&FF
http://www.musclemustangfastfords.co...5mmff_boltons/
"Silence Please
Every racer knows that free horsepower is the best kind of power, so we decided to pull apart the air filter box and remove the rubber air intake silencer. The purpose of the silencer is to draw in air from the inner fender and direct it into the plastic filter box. The rubber silencer has a funneled opening to improve flow, but the opening is small and removing it opens up a larger hole in the plastic filter box for the engine to breathe through.Best of all, removing the silencer is as simple as removing the box and prying the rubber silencer away with your hands. We did just that, and then we replaced the filter box, still using the stock filter.
And as expected, removing the silencer worked, increasing power to 223.6 from 219, while peak torque fell a hair to 263 lbs.-ft. However, average power climbed to 184.8 horsepower and the torque average also climbed to 223.5 lbs.-ft., even though the peak was down. An added bonus was that we could now hear a big whoosh of air as it rushed into the 4.6 mill and it sounded good."
http://www.musclemustangfastfords.co...5mmff_boltons/
"Silence Please
Every racer knows that free horsepower is the best kind of power, so we decided to pull apart the air filter box and remove the rubber air intake silencer. The purpose of the silencer is to draw in air from the inner fender and direct it into the plastic filter box. The rubber silencer has a funneled opening to improve flow, but the opening is small and removing it opens up a larger hole in the plastic filter box for the engine to breathe through.Best of all, removing the silencer is as simple as removing the box and prying the rubber silencer away with your hands. We did just that, and then we replaced the filter box, still using the stock filter.
And as expected, removing the silencer worked, increasing power to 223.6 from 219, while peak torque fell a hair to 263 lbs.-ft. However, average power climbed to 184.8 horsepower and the torque average also climbed to 223.5 lbs.-ft., even though the peak was down. An added bonus was that we could now hear a big whoosh of air as it rushed into the 4.6 mill and it sounded good."
01-27-2005, 02:27 PM
#4
2nd Gear Member
Join Date: Jan 2005
Location: Cinci
Posts: 238
RE: Free Horsepower
No don't forget it. It is a good post. There in conflicting reports on the removal of the silencer. I am still uncertain but after reading the article I went out at lunch and removed it. It is hard to tell buy the seat of the pants if there is a horse power increase but it sure does sound good!! Another post on the internet claims they lost 3hp on the dyno and this said they gained. So even so this might be common knowledge for some, we need more dyno results to prove this "Free Horsepower". Any takers?
01-27-2005, 02:40 PM
#5
3rd Gear Member
Join Date: Sep 2003
Location: United States
Posts: 606
RE: Free Horsepower
the only way to tell for sure is to have someone, with a modified stang, dyno their car before and after. I think Ford did a pretty good job on the stock motor, meaning that the silencer doesn't get in the way on a stock motor. But for a modified motor, and I'm talking just small bolt on stuff like exhaust, mam, & plenum, i think the silencer would be a bit restrictive and we would be able to clearly see a difference.
01-27-2005, 06:54 PM
#9
3rd Gear Member
Join Date: Sep 2003
Location: United States
Posts: 606
RE: Free Horsepower
yup, i witnessed a little volume increase, not much but it was for the better.
i also pulled the stock mam screen, which resulted in a very noticeable power increase. i'm under the impression that aftermarket cai's are a sham, with the real benefit being the replacement of the mam / removal of the screen. to that effect, most cai kits which intend you to use the stock mam explicitly tell you to reassemble everything withought the screen in place. i noticed a significant gain, most aftermarket cai users also experience a significant gain...
since doing it, about 8 months ago, i've not experienced any problems, i belive the screen was intented to be a barrier to prevent crap (small pebbles) from falling into the intake during replacement of the air filter.
the last thing which game me "free horse power" was porting my stock upper plenum. a small improvement really, maybe 2-3 horses, but free.
i also pulled the stock mam screen, which resulted in a very noticeable power increase. i'm under the impression that aftermarket cai's are a sham, with the real benefit being the replacement of the mam / removal of the screen. to that effect, most cai kits which intend you to use the stock mam explicitly tell you to reassemble everything withought the screen in place. i noticed a significant gain, most aftermarket cai users also experience a significant gain...
since doing it, about 8 months ago, i've not experienced any problems, i belive the screen was intented to be a barrier to prevent crap (small pebbles) from falling into the intake during replacement of the air filter.
the last thing which game me "free horse power" was porting my stock upper plenum. a small improvement really, maybe 2-3 horses, but free.
01-28-2005, 04:20 PM
#10
Retired MF Moderator
Join Date: Apr 2004
Location: I live in Canada, eh
Posts: 7,156
RE: Free Horsepower
ORIGINAL: Monch
yup, i witnessed a little volume increase, not much but it was for the better.
i also pulled the stock mam screen, which resulted in a very noticeable power increase. i'm under the impression that aftermarket cai's are a sham, with the real benefit being the replacement of the mam / removal of the screen. to that effect, most cai kits which intend you to use the stock mam explicitly tell you to reassemble everything withought the screen in place. i noticed a significant gain, most aftermarket cai users also experience a significant gain...
since doing it, about 8 months ago, i've not experienced any problems, i belive the screen was intented to be a barrier to prevent crap (small pebbles) from falling into the intake during replacement of the air filter.
the last thing which game me "free horse power" was porting my stock upper plenum. a small improvement really, maybe 2-3 horses, but free.
yup, i witnessed a little volume increase, not much but it was for the better.
i also pulled the stock mam screen, which resulted in a very noticeable power increase. i'm under the impression that aftermarket cai's are a sham, with the real benefit being the replacement of the mam / removal of the screen. to that effect, most cai kits which intend you to use the stock mam explicitly tell you to reassemble everything withought the screen in place. i noticed a significant gain, most aftermarket cai users also experience a significant gain...
since doing it, about 8 months ago, i've not experienced any problems, i belive the screen was intented to be a barrier to prevent crap (small pebbles) from falling into the intake during replacement of the air filter.
the last thing which game me "free horse power" was porting my stock upper plenum. a small improvement really, maybe 2-3 horses, but free.