Thinking of getting a diesel 126
03-21-2007, 07:18 PM
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Thinking of getting a diesel 126
I was looking at the 91 350sdl and would be looking to get more power and more mpg from the car as well as svo conversion.
1. What kind of mpg and I looking at with this car?
2. What if anything can be done to up the performance?
3. How will a performance increase affect mpg
4. How will svo affect mpg and performance as well as engine life
5. What would weak points on this car be?
6. What kind of costs would I be looking at if I wanted to upgrade the performance of this car?
7. what is the best company/setup for svo? Single or Dual Tank? Lovecraft?
8. I am set on a 126 and would like the most options that come with the car, would 91 be my best choice for MY? What if anything else should I be looking at?
9. What engine is in this car?
*Thanks in advance and I have been looking on a few other forums but I am new to this diesel thing and am looking for the best option to have a daily driver that's a 126 that gets great mpg. Thanks again
** I know it has 134hp so I was wondering how much more could be got from that, and mpg is rated at 22/25, would there be anyway to increase that by a lot? mpg is most important, power can come second. I have heard some of these cars get 40-50 mpg, is that a pipe dream for this car?
1. What kind of mpg and I looking at with this car?
2. What if anything can be done to up the performance?
3. How will a performance increase affect mpg
4. How will svo affect mpg and performance as well as engine life
5. What would weak points on this car be?
6. What kind of costs would I be looking at if I wanted to upgrade the performance of this car?
7. what is the best company/setup for svo? Single or Dual Tank? Lovecraft?
8. I am set on a 126 and would like the most options that come with the car, would 91 be my best choice for MY? What if anything else should I be looking at?
9. What engine is in this car?
*Thanks in advance and I have been looking on a few other forums but I am new to this diesel thing and am looking for the best option to have a daily driver that's a 126 that gets great mpg. Thanks again
** I know it has 134hp so I was wondering how much more could be got from that, and mpg is rated at 22/25, would there be anyway to increase that by a lot? mpg is most important, power can come second. I have heard some of these cars get 40-50 mpg, is that a pipe dream for this car?
Last edited by Ashkan's C43; 03-21-2007 at 07:35 PM.
03-21-2007, 07:31 PM
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1999 E300 TurboDiesel
The OM603.970 is in this car. I know that the boost can be increased on the OM603.960 (300E '87) for a little better performance and the added boost shouldn't cost any more fuel. Just don't get crazy with the boost.
For better tech on OM603 diesels, I recommend www.mercedesshop.com forums.
As far as SVO systems. I think that it's neet the way Lovecraft is trying to offer a one-stop type deal, but the fact that his filters are mounted upside down is anerving. Really with that car and where you live, you could get away with SVO in the summer and biodiesel in the winter. If you insist on a summer/winter full time SVO, go ahead with a two-tank setup. That way you can always run off of diesel if SVO is playing havoc with your system.
PM items like a water seperator (heated if possible) and primary/secondary filter units arent a bad idea either. You may also want another fuel pump to supply pressure to the SVO lines.
Is this doable? Yes.
Is it easy? Yes, if you're a DIYer.
Can it save you money? Only if you convert it on a budget (that's the hard part).
For better tech on OM603 diesels, I recommend www.mercedesshop.com forums.
As far as SVO systems. I think that it's neet the way Lovecraft is trying to offer a one-stop type deal, but the fact that his filters are mounted upside down is anerving. Really with that car and where you live, you could get away with SVO in the summer and biodiesel in the winter. If you insist on a summer/winter full time SVO, go ahead with a two-tank setup. That way you can always run off of diesel if SVO is playing havoc with your system.
PM items like a water seperator (heated if possible) and primary/secondary filter units arent a bad idea either. You may also want another fuel pump to supply pressure to the SVO lines.
Is this doable? Yes.
Is it easy? Yes, if you're a DIYer.
Can it save you money? Only if you convert it on a budget (that's the hard part).
Last edited by anghrist; 03-21-2007 at 11:25 PM.
03-21-2007, 07:37 PM
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03-21-2007, 08:59 PM
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1999 E300 TurboDiesel
Yep,
That's the screw of the 350SDL. If you want a really reliable SD, look at the earlier w126 with the OM617 turbo. or the 87-90 with the OM603. I'm pretty sure that these used the same engine as the '87 300D OM603. The OM603s had a bad batch of cylinder heads for a while too that you want to watch for. But the OM617 is an all iron (steel) engine block and head.
I considered a W126 before I picked up my W210. I question from time to time if I made the wrong choice.
That's the screw of the 350SDL. If you want a really reliable SD, look at the earlier w126 with the OM617 turbo. or the 87-90 with the OM603. I'm pretty sure that these used the same engine as the '87 300D OM603. The OM603s had a bad batch of cylinder heads for a while too that you want to watch for. But the OM617 is an all iron (steel) engine block and head.
I considered a W126 before I picked up my W210. I question from time to time if I made the wrong choice.
03-21-2007, 10:50 PM
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Answers
I have inserte responses to the questions from the original post.
I was looking at the 91 350sdl and would be looking to get more power and more mpg from the car as well as svo conversion.
1. What kind of mpg and I looking at with this car?
This depends on several factors, running on Biodiesel will decrease your fuel economy and SVO even more. If your car is extremely well cared for, 28-30 highway (with a differential swap to the 2.46 from a 420SEL).
2. What if anything can be done to up the performance?
Maintain it very well, use good lubricants, and good fuel. Bio diesel and SVO to a greater degree will decrease performance.
3. How will a performance increase affect mpg
See above.
4. How will svo affect mpg and performance as well as engine life
See above, but may decrease engine life due to lower combustion temps, leading to more sludging in oil (if you don't use synthetic diesel oil), and coked injectors and prechambers.
5. What would weak points on this car be?
The engine will eventually become a paperweight, you will have to replace or rebuild it for about $9k
6. What kind of costs would I be looking at if I wanted to upgrade the performance of this car?
Don't bother
7. what is the best company/setup for svo? Single or Dual Tank? Lovecraft?
8. I am set on a 126 and would like the most options that come with the car, would 91 be my best choice for MY? What if anything else should I be looking at?
The only options that differentiate the later 126s from the earlier ones are that the audio system is better, and versus the 300 from 86-87, the 350 had optional passenger airbags and cd changers (rare). Otherwise, heated seats, power rear seats were extremely rare options in both cars.
9. What engine is in this car?
3.5l I6 Turbo. OM603.970A. Great when it works, but that usually isn't very long. The upside is that a new crate engine is indestructable and a proper rebuild (www.mercedesengines.net) will be too.
*Thanks in advance and I have been looking on a few other forums but I am new to this diesel thing and am looking for the best option to have a daily driver that's a 126 that gets great mpg. Thanks again
** I know it has 134hp so I was wondering how much more could be got from that, and mpg is rated at 22/25, would there be anyway to increase that by a lot? mpg is most important, power can come second. I have heard some of these cars get 40-50 mpg, is that a pipe dream for this car?
Yes, the only diesel MB in the US that can come close to that would be a 190D 2.2
1. What kind of mpg and I looking at with this car?
This depends on several factors, running on Biodiesel will decrease your fuel economy and SVO even more. If your car is extremely well cared for, 28-30 highway (with a differential swap to the 2.46 from a 420SEL).
2. What if anything can be done to up the performance?
Maintain it very well, use good lubricants, and good fuel. Bio diesel and SVO to a greater degree will decrease performance.
3. How will a performance increase affect mpg
See above.
4. How will svo affect mpg and performance as well as engine life
See above, but may decrease engine life due to lower combustion temps, leading to more sludging in oil (if you don't use synthetic diesel oil), and coked injectors and prechambers.
5. What would weak points on this car be?
The engine will eventually become a paperweight, you will have to replace or rebuild it for about $9k
6. What kind of costs would I be looking at if I wanted to upgrade the performance of this car?
Don't bother
7. what is the best company/setup for svo? Single or Dual Tank? Lovecraft?
8. I am set on a 126 and would like the most options that come with the car, would 91 be my best choice for MY? What if anything else should I be looking at?
The only options that differentiate the later 126s from the earlier ones are that the audio system is better, and versus the 300 from 86-87, the 350 had optional passenger airbags and cd changers (rare). Otherwise, heated seats, power rear seats were extremely rare options in both cars.
9. What engine is in this car?
3.5l I6 Turbo. OM603.970A. Great when it works, but that usually isn't very long. The upside is that a new crate engine is indestructable and a proper rebuild (www.mercedesengines.net) will be too.
*Thanks in advance and I have been looking on a few other forums but I am new to this diesel thing and am looking for the best option to have a daily driver that's a 126 that gets great mpg. Thanks again
** I know it has 134hp so I was wondering how much more could be got from that, and mpg is rated at 22/25, would there be anyway to increase that by a lot? mpg is most important, power can come second. I have heard some of these cars get 40-50 mpg, is that a pipe dream for this car?
Yes, the only diesel MB in the US that can come close to that would be a 190D 2.2
Last edited by Untertürkheim; 03-21-2007 at 10:53 PM.
03-21-2007, 11:18 PM
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so would the 87-90 300sdl be the better play for me? I would really like to be able to get 40mpg and was also wondering if mods like turning up the boost and having an inner cooler put in would increase my mpg? I have no problem with an eariler 126 if all I am missing is an engine with more problems better sound and an air bag for my passanger. I was mainly considering svo in order to save the most money, I don't want it to kill the engine, and I would want the best system to perserve the car as long as possible... thanks to everyone who has already replied, diesels are some very interesting cars!
03-22-2007, 12:06 AM
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so would the 87-90 300sdl be the better play for me? I would really like to be able to get 40mpg and was also wondering if mods like turning up the boost and having an inner cooler put in would increase my mpg? I have no problem with an eariler 126 if all I am missing is an engine with more problems better sound and an air bag for my passanger. I was mainly considering svo in order to save the most money, I don't want it to kill the engine, and I would want the best system to perserve the car as long as possible... thanks to everyone who has already replied, diesels are some very interesting cars!
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The EPA was wrong on the mileage estimates for the '90 - '91 350SD/SDL. Those cars would routinely see in excess of 28 mpg all around driving in the summer. Easy. My 300SDL and 350SD always got nearly identical mileage despite the extra capacity of the 3.5 liter.
As far as 40 mpg...Yeah...Don't give your hopes up.
You'd have to drive at 55 mph (maybe less) all day long on a flat with NO headwinds. The engine would need to be in exceptional (like brand new) condition to see that. I'm going to attempt a 40 mpg run myself this summer.....But it will be a MIRACLE if I achieve it.
Don't forget, we're talking about a 20 year old S-CLASS diesel here. Even the brand new W221 S320 CDI Non-Bluetec would have a terribly difficult time seeing 40 mpg.
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03-22-2007, 12:25 AM
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so would the 87-90 300sdl be the better play for me? I would really like to be able to get 40mpg and was also wondering if mods like turning up the boost and having an inner cooler put in would increase my mpg? I have no problem with an eariler 126 if all I am missing is an engine with more problems better sound and an air bag for my passanger. I was mainly considering svo in order to save the most money, I don't want it to kill the engine, and I would want the best system to perserve the car as long as possible... thanks to everyone who has already replied, diesels are some very interesting cars!
03-22-2007, 02:52 PM
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The 350SDL's are no good as far as increasing power is concerned. They are already at their designed limit, and most have suffered from the bent rod syndrome already. There is no mileage covered that determines when an engine is "in the clear" or not. My first engine went out at 88K miles. The second one just before 200K miles. I had my 2nd 3.5 liter replaced with a 3.0 liter. The 3.0 liter happens to make a little more power compared to the original 3.5, too (148 vs 134 hp). Plus, the 3.0 liter will never bend a rod. You can mash your foot to the floor at 120 - 130 mph all day long, and while the mileage will suffer, it will love every minute of it. Providing the engine is known to be a strong performer and mechanically sound.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The EPA was wrong on the mileage estimates for the '90 - '91 350SD/SDL. Those cars would routinely see in excess of 28 mpg all around driving in the summer. Easy. My 300SDL and 350SD always got nearly identical mileage despite the extra capacity of the 3.5 liter.
As far as 40 mpg...Yeah...Don't give your hopes up.
You'd have to drive at 55 mph (maybe less) all day long on a flat with NO headwinds. The engine would need to be in exceptional (like brand new) condition to see that. I'm going to attempt a 40 mpg run myself this summer.....But it will be a MIRACLE if I achieve it.
Don't forget, we're talking about a 20 year old S-CLASS diesel here. Even the brand new W221 S320 CDI Non-Bluetec would have a terribly difficult time seeing 40 mpg.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The EPA was wrong on the mileage estimates for the '90 - '91 350SD/SDL. Those cars would routinely see in excess of 28 mpg all around driving in the summer. Easy. My 300SDL and 350SD always got nearly identical mileage despite the extra capacity of the 3.5 liter.
As far as 40 mpg...Yeah...Don't give your hopes up.
You'd have to drive at 55 mph (maybe less) all day long on a flat with NO headwinds. The engine would need to be in exceptional (like brand new) condition to see that. I'm going to attempt a 40 mpg run myself this summer.....But it will be a MIRACLE if I achieve it.
Don't forget, we're talking about a 20 year old S-CLASS diesel here. Even the brand new W221 S320 CDI Non-Bluetec would have a terribly difficult time seeing 40 mpg.
03-22-2007, 03:35 PM
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The 350SDL's are no good as far as increasing power is concerned. They are already at their designed limit, and most have suffered from the bent rod syndrome already. There is no mileage covered that determines when an engine is "in the clear" or not. My first engine went out at 88K miles. The second one just before 200K miles. I had my 2nd 3.5 liter replaced with a 3.0 liter. The 3.0 liter happens to make a little more power compared to the original 3.5, too (148 vs 134 hp). Plus, the 3.0 liter will never bend a rod. You can mash your foot to the floor at 120 - 130 mph all day long, and while the mileage will suffer, it will love every minute of it. Providing the engine is known to be a strong performer and mechanically sound.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
03-22-2007, 06:27 PM
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Sorry, I have to disagree on this, modifying a 300SDL engine, especially to 400 or 500 ps, will give you an instant anchor. The reason was actually mentioned above, that the 350 engine was beyond the limit for power. Since the 350 was just a bored 300 with mostly the same internals (including the connecting rods, which ended up being the Achillies Heel), this itself shows that a 3.0 OM603 cannot be modified for more power without compromising the longevity of the engine.
03-22-2007, 11:57 PM
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Sorry, I have to disagree on this, modifying a 300SDL engine, especially to 400 or 500 ps, will give you an instant anchor. The reason was actually mentioned above, that the 350 engine was beyond the limit for power. Since the 350 was just a bored 300 with mostly the same internals (including the connecting rods, which ended up being the Achillies Heel), this itself shows that a 3.0 OM603 cannot be modified for more power without compromising the longevity of the engine.
The proof is in the pudding:
http://youtube.com/watch?v=ep-soNJ8D8Y
The green W123 is actually a 24 valve version (the OM606) 3.0 liter. The W124 at the start of the video also has the 24-valve version.
The rest of them are OM603 3.0 liters.
There is a forum dedicated to these cars, if you are fluent in Finnish:
http://www.mersuforum.net
Look for Mercedes "Super Turbos".
As far as longevity, they use the same automatic transmissions strengthened to handle the extra torque (600 ft lbs +), and their engines usually have 300 - 400K kilometers on them before they start tuning them. They are daily drivers, and I haven't heard of one wearing out yet.
And a few other clips to digest:
http://mersuforum.net/forum/viewtopi...=13577&start=0
Last edited by DslBnz; 03-23-2007 at 12:01 AM.
03-26-2007, 09:54 AM
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2006 E320 CDi, 2008 3/4 Ton Suburban, 2007 "rice rickshaw" Accord 5 speed
I was nearly there
The 350SDL's are no good as far as increasing power is concerned. They are already at their designed limit, and most have suffered from the bent rod syndrome already. There is no mileage covered that determines when an engine is "in the clear" or not. My first engine went out at 88K miles. The second one just before 200K miles. I had my 2nd 3.5 liter replaced with a 3.0 liter. The 3.0 liter happens to make a little more power compared to the original 3.5, too (148 vs 134 hp). Plus, the 3.0 liter will never bend a rod. You can mash your foot to the floor at 120 - 130 mph all day long, and while the mileage will suffer, it will love every minute of it. Providing the engine is known to be a strong performer and mechanically sound.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The EPA was wrong on the mileage estimates for the '90 - '91 350SD/SDL. Those cars would routinely see in excess of 28 mpg all around driving in the summer. Easy. My 300SDL and 350SD always got nearly identical mileage despite the extra capacity of the 3.5 liter.
As far as 40 mpg...Yeah...Don't give your hopes up.
You'd have to drive at 55 mph (maybe less) all day long on a flat with NO headwinds. The engine would need to be in exceptional (like brand new) condition to see that. I'm going to attempt a 40 mpg run myself this summer.....But it will be a MIRACLE if I achieve it.
Don't forget, we're talking about a 20 year old S-CLASS diesel here. Even the brand new W221 S320 CDI Non-Bluetec would have a terribly difficult time seeing 40 mpg.
The 300SDL's of 1986 - 1987 can withstand well in excess of 400 hp (sometimes near 500 hp) without problems. Of course you'd need to make sure you had an appropriate intercooler and turbocharger setup with a modified injection pump, manifolds and custom exhaust. No internal engine work is necessary.
The EPA was wrong on the mileage estimates for the '90 - '91 350SD/SDL. Those cars would routinely see in excess of 28 mpg all around driving in the summer. Easy. My 300SDL and 350SD always got nearly identical mileage despite the extra capacity of the 3.5 liter.
As far as 40 mpg...Yeah...Don't give your hopes up.
You'd have to drive at 55 mph (maybe less) all day long on a flat with NO headwinds. The engine would need to be in exceptional (like brand new) condition to see that. I'm going to attempt a 40 mpg run myself this summer.....But it will be a MIRACLE if I achieve it.
Don't forget, we're talking about a 20 year old S-CLASS diesel here. Even the brand new W221 S320 CDI Non-Bluetec would have a terribly difficult time seeing 40 mpg.
04-26-2007, 05:17 PM
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I will have an updated post within a few days updateing everyone on the information I have learned in an easy bullet point manner. A BIG thanks to dslbnz for exchangeing so many pms with me so I could get some answers to questions I could find in another forums... Most if not everything I will be posting will be coming from what he and forums he had mentioned looking have said.
05-13-2007, 12:40 PM
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any new discoveries?
I will have an updated post within a few days updateing everyone on the information I have learned in an easy bullet point manner. A BIG thanks to dslbnz for exchangeing so many pms with me so I could get some answers to questions I could find in another forums... Most if not everything I will be posting will be coming from what he and forums he had mentioned looking have said.
