1970, 335 Cummins, hp/tq v/s '01 5.9?

[NIsaacs]

So, has the hp/tq ratings changed over the years or are they the same?



In the early 70's, the premium power plant for a big truck was an 855 ci, 335 Cummins, Detroit was a 318 V/8 and Mack 676 ci 300 inline 6. This is flywheel power. My '01 dyno's at 335hp/850 tq, the 855 Cummins 335 was about 900 tq, again flywheel power. So, I say that if you take the 855, 335 Cummins in a big truck and install my "01 5. 9 in an identical big truck, the 855, 335 will run off and hide from the 5. 9 (360 ci).



What do you say and why?



Nick

 

[Bill Stockard]

There is a huge cubic inch advantage with the 855 and it is easily running at its rated power at 2100-rpm max and will run at that rate for hundereds of thousands of miles whereas your little 360 CID engine is running far exceeding its rated power which will shorten its life. Yep, you may run with the big Cummins for a little while, but over a million miles the 855 will still be running long after your little 360 has gone to an engine graveyard.

Bill

 

[JR]

Theres no replacement for displacement

Where have I heard that before?

 

[NIsaacs]

Theres no replacement for displacement

Where have I heard that before?

Normally I would agree but ..... can you say Chevy 454 or Ford 460 gassers? If the numbers don't lie, why would the big Cummins out pull the small one? And again, I say it will but I am not sure why.



Nick

 

[NIsaacs]

Yep, you may run with the big Cummins for a little while,



Bill

See, I don't think it will, not even for a minute, but I am not sure why I think that if the numbers on paper are the same.



Nick

 

[JR]

Normally I would agree but ..... can you say Chevy 454 or Ford 460 gassers? If the numbers don't lie, why would the big Cummins out pull the small one? And again, I say it will but I am not sure why.

Nick

Comparing gas engines to diesel is a different story all together. Diesels make much more torque due to higher compression ratios, among other things. But when comparing gas to gas or diesel to diesel, a larger displacement engine will produce more hp and torque. Bigger pistons, more fuel, larger combustion equals more energy bieng transferred to the back of the crankshaft, regardless of the "number claims"

 

[The patriot]

Youre comparing apples to oranges.

 

[Bill Stockard]

See, I don't think it will, not even for a minute, but I am not sure why I think that if the numbers on paper are the same.



Nick

Notice I wrote "you may run" with the big dogs, but not for long... :-laf



Like stated above it's an apples to oranges comparison.



Bill

 

[NIsaacs]

Youre comparing apples to oranges.

Only if hp/tq is rated different on a big truck v/s a little truck. That was my original question. Is it or is it not? Please explain so a farm boy can understand



Nick

 

[BIGNASTY]

Never cared for the 335 its tapered nose crank shaft made is risky to put a bunch of HP to it fast without snapping off the harmonic balancer but I did like the idea of the pull type compression release to make starting cold easy.

BIG



STROKE LEAGTH IS THE BIG DIFFERENCE ,LIKE D4L SAID CUBIC INCHES

 

[NIsaacs]

BIG



STROKE LEAGTH IS THE BIG DIFFERENCE ,LIKE D4L SAID CUBIC INCHES

If cubic inches is so important, how do you explain the fact that the Mack at 676 cid or the Detroit at only 568 cid will run with the 855 Cummins. I think we can all agree that the 5. 9 will run with all the pickup diesels including the larger 7. 3 Ford. Will the 5. 9 run with the 8. 3 Cummins, if they are rated the same? I say it will, yet there is a big difference in cubic inches.



Nick

 

[BIGNASTY]

If cubic inches is so important, how do you explain the fact that the Mack at 676 cid or the Detroit at only 568 cid will run with the 855 Cummins. I think we can all agree that the 5. 9 will run with all the pickup diesels including the larger 7. 3 Ford. Will the 5. 9 run with the 8. 3 Cummins, if they are rated the same? I say it will, yet there is a big difference in cubic inches.

Nick

Whats the RPM range of those other motors I have never been around much other than Cat and cummins

 

[Bill Stockard]

If cubic inches is so important, how do you explain the fact that the Mack at 676 cid or the Detroit at only 568 cid will run with the 855 Cummins. I think we can all agree that the 5. 9 will run with all the pickup diesels including the larger 7. 3 Ford. Will the 5. 9 run with the 8. 3 Cummins, if they are rated the same? I say it will, yet there is a big difference in cubic inches.



Nick

There are several factors besides displacement. Low end torque, 2-cycle vs. 4-cycle, engine ratings vs. rear wheel ratings. The hp and torque rating on your 5. 9 is an educated guess if the measurements were done on a wheel dynamometer. There may be a little overlap between a 5. 9 and an 8. 3, but durability/reliability doing the same job is in favor of the C series.



Selling medium duty trucks, I had the option of a 9. 0L V-8 or a DT466 in line 6 cylinder with the same hp ratings. I was very careful where I placed a 9. 0L V8 diesel even though it was a larger displacement. Initial cost, operating expense, miles driven per year, load/application, customer/driver expectations, durability/reliablility were factors I took into consideration.



Bill

 

[BIGNASTY]

Bill

Dont know for sure JUST ASKING I have read some of your posts it seems you dont think much of the DT466 motor or is it just me thinking wrong. I love my International truck and the DT is a runner for what it is. Its not going to set the trucking industry on fire but it has been a great motor to me.

 

[NIsaacs]

Never cared for the 335 its tapered nose crank shaft made is risky to put a bunch of HP to it fast without snapping off the harmonic balancer but I did like the idea of the pull type compression release to make starting cold easy.



BIG





Yes, the scuttle butt said it would break on the Jake too, if you rared right back off the throttle too fast, but I never encountered any problems and I had some cowboy drivers



The rpm range of all the engines mentioned are very simular.



Have you ever seen or driven a truck with the 3500 series Allischalmers? I have never seen one but I did have the smaller brother 2800 series in a log loader that was a good one.



Nick

 

[BIGNASTY]

Nick

I had to go and take a look at some of the motors that you were talking about. The 318 Detroit was a runner but not as long as the Cummins. The reason that the Detroit series motors (IMO) didn't do so well wasn't because they couldn't KEEP UP with the cat and cummins it was because the WOULDNT LAST at the RPM that those motors ran it was hard to keep them in one piece.



I know I have mentioned my experience as an O/O before we use to build motors to race up hill with loads on for cash and bragging rights. Fuel wasn't that big of a concern 35 years ago so let the fuel flow. I had a 1693 TTA another guy had a 3408 V8 cat and they were the top of the heap in BIG MOTORS. One guy from Bakersfield brought up a 8v92 AND THAT thing was a RUNNER it pulled just as hard just as fast BUT NO WHERE NEAR AS LONG. The reason being is the RPM the Detroit motors were like sitting on a GIANT blender I would not own one because you couldn't hear the radio if YOU WANTED TO. Leaking oil was a problem the joke was that you didn't have to change oil you just spin on a clean filter and KEEP ADDING OIL.

 

[NIsaacs]

There are several factors besides displacement. Low end torque, 2-cycle vs. 4-cycle, engine ratings vs. rear wheel ratings. The hp and torque rating on your 5. 9 is an educated guess if the measurements were done on a wheel dynamometer.

Bill

Bill, I think you are right, that the ratings are a guess at best. That my little 5. 9 might not even spin the 855 dyno:-laf

Nick

 

[JMetzger]

There use to be an old saying that if you saw a big puddle of oil it was either a Corvair, Harley Davidson or a Detroit Diesel.

 

[NIsaacs]

Big,

The Detriot's just sounded like they were going to blow up, actually the rpm was the same as other engines. They were fun to drive and the 2 cylinders sounded the same as v12's and all between.

Yup, the big cats were the "cats meow" for sure until the K series Cummins hit the street but were always stuck in the log woods with the front axle sunk in the turn arounds Some guys, just never could understand that if you backed off the road to turn around, you were almost never stuck.

Nick

 

[BIGNASTY]

The biggest thing was the Mechanic,the one that worked on my 1693 was from Johnson Cat he did the work just to have his name on the Crew list on the side of the truck he didnt work on the road truck side of Johnson cat he was an off highway heavy equipment mech. Took him to a hill climb one time he rode in my truck and half way up the Grapevine he wanted out he said your * F * NUTS TO DO THIS. :-laf He couldnt believe what his work and knowledge could do in an ON ROAD TRUCK. Its some pretty exciting times when the truck is REALLY DIGGING and all the sounds and shifting I MISS THE ROAD but its totally different now IT HAS TO BE DONE LEAGLE????? WHATS THAT ABOUT



The wife on the other hand went with me a few times BEFORE we got married on road trips back to my place in CA. We would run up to someone that wanted to give it a try and she WAS WAY TO INTO THIS. She is fun on the road blabbering on the CB starting I TRIED TO BY-PASS THE CUSSING FILTER just to start it she's a kick in the pants I HAD TO HAVE A FAST TRUCK TO OUT RUN THE GUY'S THAT WANTED TO KICK MY A** FOR THE I TRIED TO BY-PASS THE CUSSING FILTER SHE WAS BLABBERING ABOUT. :-laf



The only KT cummins that I had messed with was a KT 600 but it was bone stock and didnt do well against turned up kitties