Need Air Filter Ideas

[Scott & Heather]

Hey Guys,

I'm taking the coach across the country in January heading from Pennsylvania home to Michigan and then on to Portland. Leid mentioned to me when they rebuilt my 8v92TA that since it is dynoing at around 525hp that I need a new air filter to replace my ecolite. They said I need 2000cfm of flow. I have tried now for months to find a single filter solution for this with calls to Donaldson tech support, calls to K&N tech support, calls to Walker, Baldwin, etc. no one has been able to be helpful. They just say "install a twin filter setup" but that would require a major amount of fab work to ensure it all fits, is sealed and secure, and somehow is easy to maintain. I'd really love a single filter solution even if said filter is large. Can anyone recommend a place or person to call to actually get some out of the box thinking and help on this?

[6805eagleguy]

Scott I'll have to get a pic of my single filter on my series 60. If I recall it's pretty high cfm

[luvrbus]

Caterpillar should have one the 16 cylinder Cat on a generator has a big air cleaner ? where are you drawing the intake air from on your C if it cannot draw enough air from the intake a larger filter does you no good and C the factory intake is not much.Eagles you were limited because of the intake.The Houston Metro Eagles had a larger intake than the std Eagle to solve the problem 

[chessie4905]

Can you fit two of your current one with a wye connection?

[luvrbus]

The high hp 8v92 calls for 8 inch piping for the intake  fwiw

[buswarrior]

Are you avoiding the second filter, thinking of symetry???

Stuff your OCD in a jar, and stick a second matching, big cfm filter can and piping anywhere that it will fit conveniently. For a busnut, long pipe, short pipe, more elbows one way or another, matters not, so long as the engine can get the air it needs at the intake. The sewer pipe section of the home reno store is your playground.

One of the few things in bus systems that total creative practicality does not need to be censured.

Happy coaching!
Buswarrior

[tr206]

Here are some possibly choices.

https://ph.parker.com/us/en/disposable-engine-air-filters

And tubing choices.

https://www.intakehoses.com

[RJ]

I'm taking the coach across the country in January heading from Pennsylvania home to Michigan and then on to Portland. Leid mentioned to me when they rebuilt my 8v92TA that since it is dynoing at around 525hp that I need a new air filter to replace my ecolite. They said I need 2000cfm of flow.

Scott -

My 500hp 8V92 uses a single WIX 46726 air filter, which I found handles 1650 cfm flow. 6" plumbing between the filter and turbo intake. This is a completely stock system, so I would suspect that the Prevost engineers spec'd this properly. But maybe not - read on. . .

Here's some trivia you may find interesting, and then I'll circle back to your coach: Way back in the '60's, Chevy was the first domestic car to offer a turbocharged engine starting in April of 1962: the original Corvair Monza Spyder. (beat the Turbo'd Oldsmobile Jetfire to market by two weeks!) The flat-six turbo engine cranked out 150 hp from 145 cu.in, up from the original 80 or 102 hp versions. To ensure longevity, Chevy used a couple of simple, yet clever engineering details, whereas the Olds engine was considerably more complex, with much worse reliability - something that cost Olds a lot of money in warranty claims.

As with any engine, detonation can be a killer, usually by punching holes it the tops of pistons. Turbocharged gasoline engines are especially prone to detonation caused by the higher boost pressures in the cylinders compared to being normally aspirated. Nowadays electronics takes care of all this, but back in 1962 that didn't exist. Chevy's solution was to replace the normal vacuum advance distributor mechanism with a pressure-retard system that retarded the engine timing when the turbo's boost kicked in, plus the requirement for using premium fuel. I owned three turbo Corvairs ('63, '64, and a '66), and detonation never was an issue - unless I goofed and pumped in regular.

Now the other, little-known trick that Chevy used was a special muffler. The Corvair's flat six could easily wind up to it's 6,000 rpm redline, but while under full boost from the turbo at that rpm, would start to disintegrate while on the engine dyno during durability testing. Here comes the trick muffler to the rescue. This magic device was designed so that between 5,000 - 5500 rpm, the back pressure would build to the point that at 5500, the turbine side would cavitate, thus preventing any additional boost and prolonging engine life.

What does that have to do with our 8V92s? I wonder, and am only speculating here, that perhaps MCI and Prevost, in these two applications, may have "throttled" the turbos by restricting the intake and exhaust systems somewhat, thus restricting boost and increasing longevity. Clifford mentioned the high hp 8V92s require 8" plumbing, and there's a lot of difference in the air flow between a 6" and 8" pipe - it's almost double! Some fellow busnuts have replaced the big mufflers on 8V92 coaches by replacing them with a low-restriction resonator. Reported results have been somewhat more noise, but also a drop in operating temperature due to the freer-flowing exhaust.

Depending on space availability, I'm also wondering if two of the WIX 46726 with 6" outputs into a "wye" having two 6" legs into an 8" discharge might work? But, again, like Clifford said, the air intakes of the coach might not be able to handle 2,000+ CFM? Also, would have to check to see if the turbo itself can handle a 6" or 8" intake! Another piece of the puzzle to be found, eh? Interesting challenge, that's for sure.

Sorry for the novel, and I don't know if this helps or not, but, like spaghetti, I threw this out there, hoping something might stick to the wall, or at least get the thought processes rolling.

FWIW & HTH. . .

[chessie4905]

Those turbo corsair mufflers were the go to for other performance engine upgrades. Used them on my 396 Nova with Mickey Thompson headers. They were close to a no restriction glass pack and still look like a muffler. 2 1/2" inlet and outlet also. Most others were 2 1/4" max.

[luvrbus]

The MCI C has the 8 inch piping with the plastic reducing housing across to the turbo if stock ,Tom (LVMCI) just purchased the parts for the air system the one was rusted out the plastic was cracked everywhere.It is a well engineered system unless it has been cobbled up,lot of people because of the location inside do cobbled it up for space  not implying Scott cobbled his up .Tom is still trying to catch his breath for the parts $$$$$ the special inline 8 inch pre cleaner was very pricy

[Scott & Heather]

Thanks for the ideas and links. I have already purchased some piping and rubber hose connectors from intake hoses. I am not concerned about the symmetry of two filters as much as the ease of swapping in new ones. My stock intake ducting (which travels to mid way up the side of the coach and intakes through a grill up high) is all custom since the coach has a roof raise, and a completely redone body. I suspect it won't flow enough air through all that even with a high flow filter. A single filter with high flow rate will suffice and I can plumb it in and change it out when necessary. Twin filters are going to be a pain to squeeze in there and swap out.

[Scott & Heather]

BW, do you think it's safe to use PVC pipe in a hot bus engine bay? I don't want to dust my brand new engine....

Are you avoiding the second filter, thinking of symetry???

Stuff your OCD in a jar, and stick a second matching, big cfm filter can and piping anywhere that it will fit conveniently. For a busnut, long pipe, short pipe, more elbows one way or another, matters not, so long as the engine can get the air it needs at the intake. The sewer pipe section of the home reno store is your playground.

One of the few things in bus systems that total creative practicality does not need to be censured.

Happy coaching!
Buswarrior

[Scott & Heather]

Here's the setup I have now. Ecolite ducted to the intake up high. Not ideal but it works:

[luvrbus]

With the factory pre cleaner at air cleaner they could draw more air if needed it was a good system 

[luvrbus]

Here's the setup I have now. Ecolite ducted to the intake up high. Not ideal but it works:
[/quote

You will get it worked out but the piping looks like 6 inch to me