ISC 360HP or ISL 425HP??

[CraigA]

Looking into purchasing a 40' DP, any comments on the ISC 360HP, vs. the ISL 425HP. ISC 360HP is it enough HP & Torque? Really want a Tiffin Phaeton, comes with ISC 360hp. Thank you for any info or experiences.

[RVThere]

I'm right in the middle with a 400HP. PLENTY of power my MPG is between 6 and 7.

My brother in law has a 330HP. Does not complain about lack of power and gets better MPG.

[Serpa69]

Don't they say bigger is better?

[Gary RVRoamer]

The real difference is the displacement and the torque. An ISL is 8.9L and 1200 ft lbs vs 8.3L and 1050 ft lbs on the ISC. The peak horsepower difference is not all that important, since you usually don't achieve the peak anyway.

An ISC is certainly adequate for a coach of the Phaeton's weight. An ISL in a Phaeton would accelerate faster, climb hills better, etc. but that is not an option. A heaveir coach (like the Allegro Bus) might "need" an ISL, but the Phaeton should be fine without it (my opinion only).

[jimandsue60]

From my experience, I would always choose the larger engine.

It also depends on what you plan to tow. If only towing a smaller car you could easily get by with the smaller engine. If you want to tow 5000 pounds plus the larger engine would suit you better.


Jim

[BobGed]

I live in the west spending a lot of time in the mountains pulling a 4,500# toad and have no complaints what so ever with my Phaeton. Tiffin uses the same engine in the 40' with a GCWR of 42,000# and the 42' with a GCWR of 52,600#. I regularly visit the TRVN site and have yet to see any lack of power complaints from either 40' or 42' owners.

[powerboatr]

in our 40' tuscany we have the isc 360 hp but the tq is listed as 1100
it pulls very well, the only place i felt down on power was at 10k feet starting from a dead stop, it took a split second longer to get rolling
if i had a choice.....MORE POWER is better

we weigh 29900 last weight check in July
chassis is 32gvwr and 42 gcvwr

this trip i pulled a flat bed car dolly with our edge on back and never really noticed any difference in git up and go or ability to maintain speeds on cruise at 65-67 mph, even in the mountains of new mexico, heading to albur.

[RocketmanRV]

Quote:

Originally Posted by CraigA Looking into purchasing a 40' DP, any comments on the ISC 360HP, vs. the ISL 425HP. ISC 360HP is it enough HP & Torque? Really want a Tiffin Phaeton, comes with ISC 360hp. Thank you for any info or experiences.

I have a Winnebago Vectra with the ISL engine, formerly 400. This is the best engine Cummings makes. Originally designed for firetrucks and ambulences where durability and quick starts are mandnatory. Mine is perfect. Has a two stage Jake Brake which makes it great for hills and towing. I highly recommend this choice. Larry

[chicken legs]

I have the ISL 400 hp version , 40 ft . I love this set up. Great performance in the mountians and very good mpg. Best MPG is 9 with a tail wind accross SD. Tow a Dodge Dakota 4x4. Mid 8,s are common. We use the pencil method not the dash calc.as it tends be high. You will not go wrong with ISL

[Batman_777]

I have the Cummins ISC 8.3L 360hp, 1050 torque... No Complaints

I heard the Cummins 400 and 425 are throttled back on torque since the Allison will not handle over 1200 anyway. So there's only 50 lbs of torque difference. And......
Side radiators are hydraulic cooled and take up to 70hp away from the 400hp to turn it. Rear Radiators are clutch belt driven and can at times take very little hp away from the motor. So I think the hoop-la over the larger hp motors is a lot of sales marketing to get more $$$.

If the tranny cannot handle over 1200 foot pounds of torque, it doesn't matter what size of motor.

[Gary RVRoamer]

Your arithmetic is off - the ISL has 150 ft lbs more torque than the ISC. And the fan is thermostatically controlled, so only runs as much as needed.

[Batman_777]

Sorry... It is indeed 150 lbs
Just seeing if you're awake :-)