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full load on engine

"Turbo charged engines must be working under full load to obtain the restricted air flow condition. The FILTER MINDER shows this condition, even after the engine is shut down."

when is the engine considered to be under FULL load? is there a certain RPM range?
2003 U320 ISM 450


Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: full load on engine

Reply #1 –
Driving up a long grade, pedal to the metal and RPM's dropping=full load.
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: full load on engine

Reply #2 –
Highest allowable RPM at WOT (under load) would equal highest rate of airflow through the air filter.

On my engine (C8.3 300hp) that would be at the "Governed HP" RPM, which is 2400.  That is where my transmission up-shifts at full throttle.

If you register a Cummins engine at QuickServe (no cost to you), you can get all the pertinent RPM limits for any specific engine.

Cummins QuickServe Online
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: full load on engine

Reply #3 –
Real world readings can be taken after going on an uphill highway on ramp using full throttle and maxing RPM. Each manufacturer has a different allowable restriction plus readings for turbo and non-turbo engines. The Detroit 2-cycles all the least restrictions for turbo engines as they use twice as much air.

See chart below.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: full load on engine

Reply #4 –
Quote from: Chuck & Jeannie –
Highest allowable RPM at WOT (under load) would equal highest rate of airflow through the air filter.
The key is under load.  Running WOT is only part of the equation.  WOT @ maximum boost =maximun airflow required.
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon
 

Re: full load on engine

Reply #5 –
If you have a U280 or U300 or any other coach with the air intake on road level behind the rear wheels, don't expect the air cleaner to last very long, especially if you drive on dirt/gravel roads. Our air cleaner canister even had good sized twigs in it. A wet cleaner will show more restriction compared to when it's dry. About a half day project and $50 to change to a later style intake location a few feet back and about 4 feet off the ground.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)