Questions: The things I think about at work - Page 2 - PeachParts Mercedes-Benz Forum

PanzerSD · #16 10-21-2007, 03:26 AM

Quote:

Originally Posted by lietuviai

Are we talking about the same Brandon who lives in Oregon whose former SD is RIP?

Yup! Mr. Diesel Grenade himself!

Cervan · #17 10-21-2007, 03:34 AM

Quote:

Originally Posted by Hatterasguy

It could.

I have no problem running our engines up to 4,800ish, but pushing them above that at this point... I don't have $8k cash sitting around at the moment to rebuild my 603 if a rod goes through the block.

But if you have $6k burning a hole in your pocket, see if you can't run your 617 up to 6k.

With a diesel its pointless, I beleive the combustion starts to chase the piston around 4,500. Diesels are not high RPM engines, nature of the beast.

i usually sit on my rev limiter on my 1981 240d. 5200 rpm's for the 616 engine is nothing especially since the engine is OHC

Brian Carlton · #18 10-21-2007, 10:04 PM

Quote:

Originally Posted by Cervan

i usually sit on my rev limiter on my 1981 240d. 5200 rpm's for the 616 engine is nothing especially since the engine is OHC

I don't understand why you would do that.

Jim and I had a rather intense discussion recently regarding the 616. It's rated for maximum horsepower at 4000 rpm. I concluded, based upon a test drive by Steve, that the horsepower continued to build up to approx. 4500 rpm. Once these engines reach maximum horsepower, they fall off a cliff due to the massive drop in torque.

So, not only are you causing significant excess wear, and risking damage to the engine due to excessive speed, but, you're also not making any horsepower above 4500 rpm.

The entire concept of running these engines up to 5K and above just doesn't make a hell of a lot of sense.

PanzerSD · #19 10-21-2007, 10:20 PM

Quote:

Originally Posted by Brian Carlton

I don't understand why you would do that.

Jim and I had a rather intense discussion recently regarding the 616. It's rated for maximum horsepower at 4000 rpm. I concluded, based upon a test drive by Steve, that the horsepower continued to build up to approx. 4500 rpm. Once these engines reach maximum horsepower, they fall off a cliff due to the massive drop in torque.

So, not only are you causing significant excess wear, and risking damage to the engine due to excessive speed, but, you're also not making any horsepower above 4500 rpm.

The entire concept of running these engines up to 5K and above just doesn't make a hell of a lot of sense.

And honestly I never expected to make any sense, these are just some of the things that I don't know fully about these cars/engines....
At work, I don't have alot of "neccessary brain time" so my thoughts are filled with "what ifs" Spend 8 hours sanding filler on a box side and your mind tends to wander

Brian Carlton · #20 10-21-2007, 10:25 PM

Quote:

Originally Posted by PanzerSD

And honestly I never expected to make any sense, these are just some of the things that I don't know fully about these cars/engines....
At work, I don't have alot of "neccessary brain time" so my thoughts are filled with "what ifs" Spend 8 hours sanding filler on a box side and your mind tends to wander

My reference was to Cervan running the 616 repeatedly over 5200 rpm and considering it "nothing".

#21 10-21-2007, 10:38 PM

Quote:

Originally Posted by Brian Carlton

My reference was to Cervan running the 616 repeatedly over 5200 rpm and considering it "nothing".

I'm not sure that either of mine have ever seen more than about 4500. What's the point, making more noise?

Brian Carlton · #22 10-21-2007, 10:41 PM

Quote:

Originally Posted by Craig

I'm not sure that either of mine have ever seen more than about 4500. What's the point, making more noise?

Making more noise.......producing less power.........and taking a lot more risk.

#23 10-21-2007, 10:45 PM

Yup, I really don't want to leave my engine parts all over Ohio.

Cervan · #24 10-22-2007, 12:56 AM

I dont do it all the time, of course it isnt good for the engine. but it can be done without signficant effects. Its at about 4500 rpm when your going 85 MPH anyways. and we have a guy on here thats ran his 240d at 85 mph for years. and there is no possibility of these engines to suck a valve. The only thing i can see happeneing is the timing chain breaking And my chain is brand new (used a press not two ball peens to finish the job) i also advanced the timing by 4 degrees and run a little 2cycle engine oil through the tank every once in awhile, (it loves that stuff)