putting a fan on the air filter

richardkillmon · September 07, 2020, 12:36:17 PM

I anyone heard of a placing a fan on the air filter for climbing hills?
I temporary switch for needed extra air for when climbing or at high altitude.

Thanks

Rick

Beluga Bus · September 07, 2020, 02:11:14 PM

How big of fan are you thinking about(cfm). Is this fan also going to provide a pressure boost? How will you provide extra fuel for the extra air you are introducing into the cylinders? If it does not provide enough cfm and boost it will just impede needed air flow and you will loose performance.

An electric motor that is big enough to provide needed cfm and boost will draw a lot of current from your charging system. The power needed to support the electric motor will be greater than the added performance gain.

Matt

Jriddle · September 07, 2020, 02:22:24 PM

It is good to think outside of the box.

I see this as a density issue and a fan would not be able to compress the air into the cylinder.

So in my opinion it wouldn't help.

John

luvrbus · September 07, 2020, 02:28:36 PM

Quote from: Jriddle on September 07, 2020, 02:22:24 PM
It is good to think outside of the box.

I see this as a density issue and a fan would not be able to compress the air into the cylinder.

So in my opinion it wouldn't help.

John

It all about density and fuel to air ratio a electric fan is not going to help you

Jeremy · September 07, 2020, 03:11:03 PM

Part-time electric superchargers for commercial vehicles have been a thing for a while I believe. Here's a random article about them from Google:

http://www.transportengineer.org.uk/transport-engineer-news/novel-electric-supercharger-aimed-at-truck-and-bus-diesel-downsizing/64932

Jeremy

Utahclaimjumper · September 07, 2020, 03:37:27 PM

There is NO free lunch.>>>Dan

chessie4905 · September 07, 2020, 05:03:56 PM

Anyone change the blower to the high speed gears?

luvrbus · September 07, 2020, 08:16:05 PM

Quote from: chessie4905 on September 07, 2020, 05:03:56 PM
Anyone change the blower to the high speed gears?

N/A engines have a higher speed blower than the turbo engine, it take 37 hp on a 8V71 to turn the blower at 2100 rpm fwiw,that is why the bypass blower is popular on turbo equipped Detroits once going the turbo does the work

Jeremy · September 08, 2020, 02:11:42 AM

Quote from: Utahclaimjumper on September 07, 2020, 03:37:27 PM
There is NO free lunch.>>>Dan

I don't think anyone is claiming that there is anything 'Free' about it, just people looking for a way of boosting the engine power output for short periods. Kinda similar in principle to using water injection or even nitrous oxide on a petrol engine - you can't do it continuously, but for short periods it's proven technology

Jeremy

dtcerrato · September 08, 2020, 04:43:09 AM

You didn't mention propane injection...

Jeremy · September 08, 2020, 03:09:31 PM

Is propane injection on diesels used in this kind of way (getting up hills faster etc)? I thought it ran continuously and was more an emissions-reduction thing.

Jeremy

Beluga Bus · September 08, 2020, 05:27:04 PM

Propane is can be a power adder to a diesel just as nitrous is to a gas engine. Any time you add power you also add heat. Pull the length of Baker grade in the summer on propane, or using any other method to add power will really test your coolimg system.
Matt

dtcerrato · September 08, 2020, 05:57:33 PM

I made mention of propane because prior to our recent in-frame the 671 was getting really tired. Well during our first Alaska road trip From Florida I have to say that the DIY propane injection system was a world of help. As far as going faster or more power it's really not that cut & dry. I will say on those pesky lloonngg slight grades & especially mixed in with a head wind - that's where the propane was a great help. Probably saved a gear downshift lots of times but never really felt it at the seat of the pants. In an earlier post Clifford mentioned that I was wasting my time installing pyrometers in a 671 - well his statement was very true. I was nervous about the injection system so I installed dual pyrometers - one in each dual exhaust manifold. On that 12,500 mile round trip - had lots of time to play with it on & off. It made absolutely no difference in EGTs with or without propane injection - hills or flat. 950 degrees is where it usually topped off at but we're talking a purely stock 671. If it were to produce more than the 200+ HP we run then the EGTs may climb a little - I really don't know. The fact is when propane in being injected the diesel is tapered back by the governor so there is truly no added heat build up. At that point I figured the pyrometers were worth it just to iron out those unknowns. On the more recent 2nd AK road trip we didn't use the propane injection because after the in-frame the engine seemed to have "woke up" but we still have the system intact & would use it if the need arose. I guess we were (are) being conservative with a really good strong running 671... It was a really exciting experiment if nothing else...
It's a turtle but a dependable one that'll get ya there all the time and sometimes we can literally smell the roses as they go by so slowly...

buswarrior · September 08, 2020, 06:22:07 PM

Excellent write up dtc!

The issue is available air to mix with whatever fuel is in the cylinder.

All the air is handily used by the diesel, which has more btu than propane, any smoke indicates that all the air got used, and there was fuel left over.

A busnut after more power, needs to find more air.

The fuel part is the easier job.

Happy coaching!
Buswarrior

uncle ned · September 08, 2020, 06:40:22 PM

Does anyone remember the cat show where the guys tried to supercharge a car with gas powered 200mph leaf blowers.

I think they put 4 or 5 of them on there.

uncle ned