Community Forums

GaryG · 04-17-2007, 09:45 AM

At the recent RV show in t. Lauderdale My wife and I fell in love with a Monaco Knight 40 DFT. I was the only foorplan we saw with 1 and 1/2 baths. I currently own a 31ft. TT and am new to motorhomes. This coach comes with the 330 Cummins. I noticed other models came with the 400. Am I better off with the 400? Problem is I haven't found it in the floorplan we like. We do travel to Colorado every summer and have to pull passes. I also plan to pull a small 4x4 toad. Any input would be greatly apprciated.
Thanks!

GaryG · 04-17-2007, 09:45 AM

At the recent RV show in t. Lauderdale My wife and I fell in love with a Monaco Knight 40 DFT. I was the only foorplan we saw with 1 and 1/2 baths. I currently own a 31ft. TT and am new to motorhomes. This coach comes with the 330 Cummins. I noticed other models came with the 400. Am I better off with the 400? Problem is I haven't found it in the floorplan we like. We do travel to Colorado every summer and have to pull passes. I also plan to pull a small 4x4 toad. Any input would be greatly apprciated.
Thanks!

Gary RVRoamer · 04-17-2007, 02:31 PM

If it is the ISL engine (probably is), then you will hardly notice the difference. I have an ISL 370 myself. All the ISL's are identical 400 HP engines with the lower horsepower models simply detuned slightly to reduce the peak HP. This is done via parameters in the engine computer, not with mechanical changes. The torque and available horsepower will be the same in nearly all situations and the 330 is plenty to haul you through those mountain passes.

digNbubbs · 04-17-2007, 08:37 PM

I have a Knight with the 330 Cummins and pull a Jeep Wrangler. California to Florida and half way back, have had not issues with power. I have been very happy with the ride, merging, passing, etc.

More is usually always better, but I have no reason to wish this 40 footer had a 400 (yet).

--kevin

GaryG · 04-18-2007, 02:32 AM

It is an ISL. I looked up the specs on Monaco's web site. The 330 has 900lb/ft torque and the 400 has 1200lb/ft torque. It sounds like 30% more torque. I'm going to have to think on this one.
Thanks for your feedback!

Roland · 04-18-2007, 03:10 AM

Gary,

Also compare the weight of the units to the horsepower. Diesel engines are sized to the weight of the coach. Rough rule of thumb: 1 horsepower for each 100 lbs. of weight. My '01 Dip weighs just under 30,000 lbs. and I tow a Grand Cherokee at approx. 4,500 lbs. I have an ISC-330 Cummins. I can go up a 6% grade at about 42 to 50 MPH and I don't try to firewall it, all the time. Gives me time for some coffee and to smell the roses.

Green lights and soft breezes

Ecker · 04-18-2007, 03:55 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by GaryG:
At the recent RV show in t. Lauderdale My wife and I fell in love with a Monaco Knight 40 DFT. I was the only foorplan we saw with 1 and 1/2 baths. I currently own a 31ft. TT and am new to motorhomes. This coach comes with the 330 Cummins. I noticed other models came with the 400. Am I better off with the 400? Problem is I haven't found it in the floorplan we like. We do travel to Colorado every summer and have to pull passes. I also plan to pull a small 4x4 toad. Any input would be greatly apprciated.
Thanks! </div></BLOCKQUOTE>

For all practical purpose, you'll not notice the difference. The models have 400 probably are heavier and thus they will have same performance as 330. Moreover, torque is specified as Peak at some RPM. Ignorng the weight issue, one would still have to look at torque curves for the other models to see if it would be any different when running at "normal" RPM levels i.e. the curve may fall off faster for one vs the other. And finally, you'll pay in fuel economy for larger engine.

Bottom, line unless one is a Type A personality focused on running as fast as possible up hill and dale, the 330 should do fine.

GaryG · 04-18-2007, 05:40 AM

The coach weighs 33,000 lbs. The next model up (Diplomat) weighs in about the same and has the 400. Both torque measurements are listed at 1300 rpm.
I really appreciate the responces I'm getting.This isn't an easy decision.

MonacoMama · 04-18-2007, 06:44 AM

Garyg,
Got to butt in here. They have the same chassis and weights, but the Knight has :::Cummins® ISC 330 Engine with Allison® 3000 MH 6-Speed World Transmission and Electronic Shifter
Engine Displacement: 8.3L/506 Cu. In.
Torque: 950 lbs./ft. Max. Net at 1,300 RPM
The 400 has 1200 lbs.

digNbubbs · 04-19-2007, 06:04 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by MonacoMama:
... They have the same chassis and weights... </div></BLOCKQUOTE>

I'd be curious to see the GVW of both. I would think that the Dip would have a higher rated GVW than the Knight. I think the Knight rolls at 33k GVW (not at the coach right now

). I know the Dip has some cool, heavier options (such as real tile vs. vinyl, larger TVs, etc). I think I am rolling @ ~31k loaded, ~35k towing.

If the Diplomat weighs in the same, I would think it may get a little better mileage with the 400??

--kevin

SacsTC · 04-19-2007, 06:16 PM

Hi Kev,
Both coaches have the same Chassis and GVW/GCVW, 33,000/43,000. CCC may be less on the Dip if the available options weigh out to be more than on the Knight.

Cruzer · 04-20-2007, 03:26 AM

The ISC will do the job. It's just that the ISL will do it better. Back when I worked on trucks we had tractor-trailer rigs pullling coast to coast with 230-250 HP Cummins NH series engines. However, it wasn't the horsepower that got them there, it was the 1,600+ ft-lbs of torque from the 14 liter engines that did the job on a 60,000 lb rig.

The 8.3 liter ISC 330 with 950 ft-lbs of torque will handle the mountains. There's plenty of 7.2 liter Cat 330s with 860 ft-lbs that are making it okay. However, the 8.9 liter ISL 400 will do a mich better job at 1,200 ft-lbs of torque. They'll both do the job, it's just that the ISL 400 will be more pleasing to drive.

One other area you'll notice a difference is in the engine brakes. The ISC has an exhaust brake while the ISL 400 has a true "Jake" style engine compression brake. The ISL's Jake brake does a much better job of retarding your speed when coming down those mountain grades.

digNbubbs · 04-20-2007, 06:00 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by SacsTC:
Hi Kev,
Both coaches have the same Chassis and GVW/GCVW, 33,000/43,000. CCC may be less on the Dip if the available options weigh out to be more than on the Knight. </div></BLOCKQUOTE>

Ah - makes sense.

--kev

GaryKD · 04-20-2007, 06:02 PM

From one Gary to another, size does not always matter. Per my signature, I have the smaller of the engines you are considering. With this coach, I have been all over the USA East of the Mississippi River. In the mountains of West VA, VA, Eastern Tenn, etc the coach performed quite well. If I can keep up my momentum, I can stay out of the truck lane and move right along. If I loose my momentum, it's in the truck lane and patience is the name of the game. Overall I am very pleased with the engine.