New to irv2. 380hp vs 450hp?

[vito.a]

Keith. when comparing diesel engines ask for the torque rating. The reason is several coach manufacturers are using the little Cummins ISB (think Dodge pickup) in large motor homes. The highest torque rating on these is 800 ft lbs while most are rated at 660 ft lbs.

The Cummins ISL 450hp engine is rated at 1250 ft lbs and will do a much better job in a heavy motor home.

There is a chance the 380hp engine is a de-rated Cummins ISL. If so, then it's rated at 1150 ft lbs and may be adequate.

[Crasher]

I believe both models you are looking at are on the Powerglide chassis, so both will have IFS. Don brings up a valid point. If the Phaeton just has the Exhaust brake, the Compression brake on the Bus will offer much better speed control descending a mountain.

[Ray,IN]

Looking at HP may not help. IMO you should look at the HP to weight ratio. It seems the industry standard is 1 to 100. Ratios higher than that mean slower grade speeds.


It is my opinion a buyer should avoid a DP with the Cummins 6.7 ISB engine due to lower torque available. MH mfgrs. use this engine to keep prices down.

[Dutch Star Don]

Originally Posted by Ray,IN

Looking at HP may not help. IMO you should look at the HP to weight ratio. It seems the industry standard is 1 to 100. Ratios higher than that mean slower grade speeds.


It is my opinion a buyer should avoid a DP with the Cummins 6.7 ISB engine due to lower torque available. MH mfgrs. use this engine to keep prices down.

I sure agree with this. When they eliminated the ISC, they really put too much of a load on the ISB to perform in larger coaches.

[Dsrtrider]

I have an Allegro Bus 37AP with the isl 450 1250 torque I was stuck behind 2 trucks i was down to 35 mph i was able to downshift and get around and pass them. I would get the 450 with side radiator also does the Phaeton have IFS ? thats why we bought a Bus . Just came from a gas coach in the last month. Good Luck on your choice

[augerdogger]

I would sit back and enjoy the drive. I have a Cummins ISX 1650 ft-lbs torque and 500 hp. I just get in line with the big trucks and follow them. Being retired I am no longer in a hurry. I let Collision Mitigation set speed and distance from vehicle in front. I have done my share of mountain passes and always made it to my destination.

[cbr46]

Both will get up the mountains and not disappoint like your gasser did.

Buy the coach that you LIKE more.

But if you want to MAXIMIZE your climbing ability divide weight / torque (or weight / hp if you want to scream it) and pick the higher number.


- bob

[Craig L]

Thats not that much difference in HP. I would look at vehicle GVW and compare that. I only know previously had a 400 Cummings on our Coach. We got passed going up all hills, and it overheated anytime you loaded it on a hill. We bought a HR 45’ with a 650 Cummings, problem solved.. good luck

[Ryancasey]

Go big or go home, u won't regret it.

[2cyber71]

Originally Posted by Crasher

I've had both. The 380 in our 2011 40' Phaeton did the job well towing an Avalanche toad. However, we don't mind going up to the Eisenhower Tunnel at 40 mph. The scenery is great. Now we have a heavier 2013 43' Bus with the 450 ISL. Guess what, we still go up to the tunnel at 38-40 mph towing a 6300# Avalanche. The 450 only has 100 more ft lbs of torque, so less than 10% increase. You will see a difference in performance in the mountains, but it isn't enough to be a deciding factor if you prefer the Phaeton interior. No reason to be concerned about running at 100% power with either engine. The ECM on either is a lot smarter at protecting the engine than any operator. It will cut back the power before it allows anything to go bad. More than likely the 380 can be flashed to 450 for under $1,000. The Transmission is good up to 1250# of torque and the side radiator "should" be able to keep it cooled. Others have done it with no issues. My advise is to ignore the engine and go with the coach that gets you what you want most. Just remember, when full timing, you will be driving it less than 3-4% of the time and "Living" in the rest. On the level, both will perform equally. You "Might" want more power less than 5% of the time you are traveling. What's more important to you???

Great answer.
It’s all here

[DryCreek]

Originally Posted by H2omanboston

Hello,
New to irv2 so please bare with me.

OK, I'm nekkid. What's next?

[Newps]

Originally Posted by DryCreek

OK, I'm nekkid. What's next?

Now go buy a "Cummings".

[DSDP 2002]

Originally Posted by H2omanboston

Hello,
New to irv2 so please bare with me. Hope all of you are well & kicking.

Wife & I are looking to buy a used diesel motorhome later this year. Been campers all our lives. Will retire in 3-4 yrs and then live in our motorhome for as long as we can.

Looking at Tiffin Bus 40AP or Phaeton 40AH. My question is with the engines & power to handle the mountains.
I prefer the Bus 450hp to make sure I don't have to worry about power thru the mountains/rockies while having a mid-size toad. Or, will the Phaeton 380hp be enough to handle these kind of mountains and not have to worry about having to "go around" ?? My last motorhome was a gas powered, so I was easily passed on the hills while I barely hit 40mph. Don't want that again. I know diesel is different and better, I just don't know what I really need for engine power. 380hp vs 450hp?

Anyone with experience btw these 2 engines and what might really be needed to scale the mountains would be greatly appreciated. Any thoughts or comments are welcome. Thank you and look forward to hearing from you.

Keith

Hello Keith, FYI, we are living in our 2002 40 Tiffin bus while our home is being built. We will offer the MH for sale late summer/early Fall when the house is completed. mroplanner@yahoo.com if interested, currently in coastal NC.
Ed

[tropical36]

Originally Posted by H2omanboston

Hello,
New to irv2 so please bare with me. Hope all of you are well & kicking.

Wife & I are looking to buy a used diesel motorhome later this year. Been campers all our lives. Will retire in 3-4 yrs and then live in our motorhome for as long as we can.

Looking at Tiffin Bus 40AP or Phaeton 40AH. My question is with the engines & power to handle the mountains.
I prefer the Bus 450hp to make sure I don't have to worry about power thru the mountains/rockies while having a mid-size toad. Or, will the Phaeton 380hp be enough to handle these kind of mountains and not have to worry about having to "go around" ?? My last motorhome was a gas powered, so I was easily passed on the hills while I barely hit 40mph. Don't want that again. I know diesel is different and better, I just don't know what I really need for engine power. 380hp vs 450hp?

Anyone with experience btw these 2 engines and what might really be needed to scale the mountains would be greatly appreciated. Any thoughts or comments are welcome. Thank you and look forward to hearing from you.

Keith

Rule of thumb is 10hp per foot which translates to the amount of torque as well and should be more than adequate even for towing, unless you're a young hot rod, so the Phaeton comes up a little short.
More importantly go with a side radiator for overall coach quality and ease of Maintenace, which the bus has and would certainly be my pick of the two.