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Turbo diesel swap

Boooy that is some creative mathematics. SMP dude, wow. Just.. wow.

I'll remind everyone here that sdturbo is the only person that actually has a non-volvo swapped diesel 240. And that dieselboy is the only one showing what he's got in the way of 617's.

And again, anything and everything a 617 can (and cannot) do is pretty well detailed via the (working) search button on the peachparts.com forum. (formerly MercedesShop before the big German copyright jackboot stepped down).
 
Poik said:
Uh, smp375, engines are rated at peak output, the torque curve is just that, a curve. It's not a flat line where you can calculate HP based on any RPM given the rated torque of the engine. It doesn't work like that.
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How does it work, Poik? Given the fact the torque peaks around 1800 RPM's and begins to drop off somewhere around 4700 RPM's and horsepower = (torque x RPM)/5252, how would you go about calculating horsepower?
 
I find it interesting that you guys continue to belittle me, but have yet to offer or support a single counterpoint. I'm willing to admit when I'm wrong, it happens to every single one of us from time to time. Show me some numbers!
 
smp375 said:
How does it work, Poik? Given the fact the torque peaks around 1800 RPM's and begins to drop off somewhere around 4700 RPM's and horsepower = (torque x RPM)/5252, how would you go about calculating horsepower?
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Uh, then you can calculate the HP for the ONLY DATA POINT YOU HAVE.

If it is true that the peak torque is 180ftlb at 1800rpm, then the HP at 1800rpm is 62hp. And unless you have another data point, that's all you can calculate. You can't just make up numbers and then calculate based on made up estimations, which obviously led you to a number that was 30% off the manufacturers rated HP for the engine. You need to know the torque value at 4700rpm to calculate the HP, you can't just say "it begins to taper off somewhere around 4700" and stick a number to it.

Also, if the torque peaks at 1800rpm, that means it starts dropping off past 1800rpm. So your statement is conflicted.
 
smp375 said:
I will admit my cars did surprise me with how high they could rev if I held it in low gear, but I remember correctly the torque curve ends somewhere between 4200-4700 RPM's; I know for a fact the output is rated by Mercedes Benz at 180 ft. lbs. and 120 HP, but I imagine the max HP number is probably a little higher, considering the fact the engine can rev quite a bit higher than MB rates. Starting at 180 ft. lbs, 265 ft. lbs. is a 67% increase, which I know is significant, but that is not unheard of with significantly higher boost pressures. So, let's say I overestimated by roughly double, a 35% increase is still 243 ft. lbs, which equates to 217HP at 4700 RPM and 254 HP at 5500RPM. However, when I actually calculate the stock horsepower from 180 ft. lbs. at 4700 RPM's it comes out to 161HP, so we can all see where there can be some discrepancies. No, I didn't pull these numbers out of my ass, I pulled them out of my calculator; pull your head out of your ass and pick one up sometime, "sdturbo."


Maybe I don't know anything about the Mercedes 5-cylinder turbo, I'm sure that's why people keep bringing them to me when they can't get their's running right.
You guys can laugh and poke at me all you want, you're only making yourselves look like douchebags. Maybe I overestimated what can be achieved without injection pump modifications, but that doesn't make me an idiot, that only means I may have made a mistake. Just remember, there is always more than one way to achieve power gains out of any and every engine, and just when you think you've got a good understanding there will always be somebody else to accomplish something you didn't know was possible. Guess what, I happen to be a guy that accomplishes things with engines other people didn't think was possible. I guess I probably am an idiot for thinking my 22 years of automotive experience could offer anything to anbody when they have few self-righteous, over-confident, closed-minded assbags with all the knowledge in the world, to "help."

"CFL940," I wish you all the luck if you do go ahead with the build. If you are able to complete it, I think it will be great. To the rest of you, good luck carrying all that knowledge, it must be a huge burden to know it all.
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Not to be a jerk, but when someone makes statements that are demonstrably false (like saying you can make 220+ hp out of a "low-redlining" OM617 without major pump modifications) they're going to get called out on it. I don't think anyone insinuated that you don't know how to work on cars, so please don't pull the "I've been doing this for X number of years, so I know what I'm talking about" card. I used to take my vehicles to "good ol' boy" know-it-all mechanics that had (supposedly) been working on cars forever. I got tired of them ****ing my cars up on my dime, so I learned how to do it myself. Since I've started doing all of my own work (including the "major" ones) I've come to realize that a lot of the "good ol' boy" know-it-alls get away with sloppy, **** work and in all reality shouldn't be let anywhere near other people's vehicles.

Since you obviously know what you're talking about, why don't you post up some pics and dyno-charts of some of these mythical low-revving, 220+ HP OM617's with no internal pump modifications that have gotten the rest of us so chatty? Have a nice day.
 
Poik said:
Uh, then you can calculate the HP for the ONLY DATA POINT YOU HAVE.

If it is true that the peak torque is 180ftlb at 1800rpm, then the HP at 1800rpm is 62hp. And unless you have another data point, that's all you can calculate. You can't just make up numbers and then calculate based on made up estimations, which obviously led you to a number that was 30% off the manufacturers rated HP for the engine. You need to know the torque value at 4700rpm to calculate the HP, you can't just say "it begins to taper off somewhere around 4700" and stick a number to it.

Also, if the torque peaks at 1800rpm, that means it starts dropping off past 1800rpm. So your statement is conflicted.
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Okay, then let's reverse calculate this. Let's assume, just for sake of discussion, that the rated 120 HP is at 4700RPM; can we agree that is probably accurate?
(120hp x 5252) /4700 = 134 ft. lbs.
Given this calculation, I can see I was further off than I thought, but not quite as far as you have suggested. So if I add a 35% torque increase at 4700 RPM I can now see that HP at that RPM is only 161. If a person was able to pull a 67% torque increase out of the engine, that is still 200 hp at 4700RPM. Yes, that is quite a bit lower than I had initially calculated; forgive me for my error. I did actually believe that those engines maintained peak torque up to about 4700 RPM.

Regardless of the fact that I was wrong, my error does not excuse the douchebagery that ensued. I find it hilarious that four of five of you chose to laugh at me, and insult me, yet only one of of you could be bothered to offer anything to continue a discussion. Instead, you felt the need to flex your figurative muscles and attack me, which accomplished nothing. It seems to me that if you guys really do know as much as you think, you could have offered a constructive counterpoint with some supporting figures so we could have had a productive and respectful discussion in which I would have conceded to my mistake a helluva lot sooner.

Poik, I do appreciate the fact that you actually treated me with some respect, and did continue an actual discussion. Thank you!
 
745 TurboGreasel said:
TKO600 $2000 without clutch bellhousing, shifter, or shipping. Still gonna build one?
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was hoping for something different. Black smoke racing is getting a new gearbox and the have the TKO600 on the engine right now. maybe you can contact them if you can get it from them. (if shipping from finland isn't more expencive than getting a new one :p)


dieselboy said:
Sorta but you will need a injection pump with bigger elements. (big$) 1000$+
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Also black smoke racing can help you out; they sell 7mm elements for 50€ (~75$ at the moment) a piece

this thread will get you going.
 
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Actually, I just looked it up. According to wikipedia (just the first source I found with a quick search) the power ratings are:

123 hp @4350
181 ft. lbs @2400.
 
smp375 said:
Okay, then let's reverse calculate this. Let's assume, just for sake of discussion, that the rated 120 HP is at 4700RPM; can we agree that is probably accurate?
(120hp x 5252) /4700 = 134 ft. lbs.
Given this calculation, I can see I was further off than I thought, but not quite as far as you have suggested.
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It's plausible that's where the peak power is. You calculated 161hp, rated is 120hp. 161hp is 34% more than 120hp. I rounded down and just said 30% :e-shrug:
 
And not to **** on oil burners, that I love dearly and drive one every day, but for the power and the average mileage and the cost of fuel, a redblock is cheaper to operate. Just saying.
Wasn't the case years back when #2 was below reg unleaded, but we'll never see that again.
 
wolf_walker said:
And not to **** on oil burners, that I love dearly and drive one every day, but for the power and the average mileage and the cost of fuel, a redblock is cheaper to operate. Just saying.
Wasn't the case years back when #2 was below reg unleaded, but we'll never see that again.
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cant run a redblock on WVO tho
 
I can't help but think the price of diesel is rigged, so as to negate any cost savings to be gained from the superior fuel economy of diesel-powered vehicles.

Also not sure if this was mentioned earlier in the thread, but 78-79 300sd's were equipped with a (more) failure-prone 3-speed slushbox compared to the 4-speeds in the 80-84 models.
 
bricklovermike said:
I can't help but think the price of diesel is rigged, so as to negate any cost savings to be gained from the superior fuel economy of diesel-powered vehicles.

Also not sure if this was mentioned earlier in the thread, but 78-79 300sd's were equipped with a (more) failure-prone 3-speed slushbox compared to the 4-speeds in the 80-84 models.
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Tend to agree. I have been daily driving a diesel since 97 or so and have watched the price of the stuff keep creeping up, and the quality keep creeping down (least for old junk). It used to run under unleaded, and the price fluctuations were slower. Gas would go up, week or three later, diesel would crawl up, but less total. Likewise the going down. Then it was as much as mid-grade. Then premium, now it's over that as often as not, and it fluctuates much quicker. I'd say it's rigged, yeah. But at 42mpg I still don't pay much attention to it, it costs exactly twice as much to drive my 244 to work and back for a week as it does the Rabbit. It's yet to get expensive enough for me to want to dick around with alternative "free" fuels. Though it is interesting to watch. :)

I remember a few years ago I had a really nice little 8v Scirocco that was tuned to the hilt, bone stock but ran perfect, we do a lot of K-Jet Porsche crap so I've had opportunity to get comfy with it and learn a few tricks. Anyway, not only would it outrun my buddys TDI Jetta, but at 38mpg (combined mind you) in the Rocco and 44 in the Jetta, with the price of fuel it was cheaper to drive mine. Likewise, my 745T M46 car got about the same MPG as the last good running W123 300D I had, and with cheaper fuel, well. Just observations.
 
gross polluter said:
Or the process of de-sulphation was added. But hey, you're the expert.
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Well, I wouldn't call myself an expert, but I am aware that desulphation is a process that causes batteries to fail, not a process used to remove sulfur from diesel fuel; I suppose it's you that is the expert. I also know the war in Iraq started in 2003 and the cost of diesel fuel began to climb in 2004, while the Ultra Low Sulfur Diesel requirement didn't take effect until September 1, 2006. I also know, because I bothered to read about it rather than lash out, that the refinery's operating cost of producing ULSD is about 2.5 cents per gallon. I'm sure refineries passed most of the - $600-750 per barrel per day capacity - cost they incurred in adding the technology required to meet that requirement on to consumers through higher fuel costs at the pump, but it's unlikely that was only applied to the cost of diesel fuel at the pump, rather it would more likely have been distributed almost evenly amongst their entire product line.

:cool: Hmmmmmm...maybe I do know something :rofl:
 
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