Does cooler weather really enhance engine performance?
Tourer
Joined: May 2011
Posts: 324
Likes: 8
From: Florida
Yes. Cooler dense air enhances performance. When I built a supercharged (roots blower) car several years ago installed trunk mount methanol injection to the throttle body. Same result a cooler intake charge increases HP.
Nah man that's what methanol does. Roots blowers actually create heat, their job is just forcing more air into the motor. The down side with roots blowers is the more you try to spin them via changing the pulley for more psi boost, the more heat they create, and they start forcing hot air in, and hot air as you've leaaned is not as dense air, so you start losing power gains. running methanol will help counteract this
Last edited by Ink83; Sep 28, 2015 at 04:26 AM.
Advanced
Joined: Mar 2015
Posts: 89
Likes: 20
From: Alabama
Supercharging
Supercharging Vs Turbosupercharging - worked on a program years ago where we were investigating using an electric motor to drive a supercharger. We ended up baselining an engine and then adding the three options, belt driven, electric motor or turbo. Although all three methods add heat to the intake air, you are forcing more oxygen into the engine; that is similar to a colder, denser air, but to a greater degree.
One of the things that became apparent was the belt driven supercharger's power demand. As we increased boost via pulley ratio it drew increasing amounts of power. We got increasing power but the percentage over what we were losing to the supercharger diminished with each ratio change. The electric motor didn't impact engine power negatively but the motor size became prohibitive when trying to match the belt drive. The turbo was the most efficient but the lag was a problem. This was a time before Garett and others became serious about turbocharging and resolved a major portion of the turbo lag.
Oh, I forgot to mention detonation. As we increased boost we began adding a water/alcohol mix to combat the problem. Since the intent had been to offer this product to the public, and knock sensors had not yet been introduced, we became concerned. Can you really trust the average driver to ensure he keeps the water/alcohol container full? Do you disarm the supercharger if you detect the container is empty. The deeper we got into the project the more we uncovered reasons to drop it.
One of the things that became apparent was the belt driven supercharger's power demand. As we increased boost via pulley ratio it drew increasing amounts of power. We got increasing power but the percentage over what we were losing to the supercharger diminished with each ratio change. The electric motor didn't impact engine power negatively but the motor size became prohibitive when trying to match the belt drive. The turbo was the most efficient but the lag was a problem. This was a time before Garett and others became serious about turbocharging and resolved a major portion of the turbo lag.
Oh, I forgot to mention detonation. As we increased boost we began adding a water/alcohol mix to combat the problem. Since the intent had been to offer this product to the public, and knock sensors had not yet been introduced, we became concerned. Can you really trust the average driver to ensure he keeps the water/alcohol container full? Do you disarm the supercharger if you detect the container is empty. The deeper we got into the project the more we uncovered reasons to drop it.
Last edited by Jimmy Knuckles; Sep 29, 2015 at 07:41 PM.
Outstanding HDF Member
Joined: Mar 2006
Posts: 3,411
Likes: 22
From: Connecticut
To give Softail riders info so they can keep up with Dyna riders. LOLOL
Sammi
Sammi
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Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
Good luck with that. Softail owners are pretty dense. Heck they bought a softail after all.
Road Master
Joined: Aug 2015
Posts: 809
Likes: 39
From: Duluth, MN
and 96.7% of all facts are made up on the spot....