83 w123 300d twin turbo intercooler
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83 w123 300d twin turbo intercooler
has any one done this or heard of someone who did. my car is like new in & out. w/105k mi. looking to make the all time cruser w/it. i am a ase cert. master mechanic. but have not heard of any one w act experince with this, and alltho i own a merc. i do not genrealy work on them. can you advence the pump? is there a bigger pump avable? injectors? wastegate mods? psi increase? any reply.
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From: California,Washington,St.Croix
Very Slow Mercedes
What are you after the wow factor or power?.....The injection pump may be a problem but there is a guy in Long Beach, CA that can answer about if the injection pump can provide for more boost--Dumars Diesel not sure on the spelling but he is the one..I asked him about this myself when I wanted to a 68 280SE coupe i had which uses a similiar injection pump, I don't remember his answer....but I must say you are a bit mad and I mean crazy and I do mean that in a nice way....
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From: Federal Heights, CO
1982 300D VNT, 1980 240D 3.0T, 1982 300TD
This forum is better for these types of questions and you will have many members with similar gols: http://schumanautomotive.com/forums/...splay.php?f=19
Twin turbo is impractical for a few reasons.
1: You have 5 cylinders, simple math will tell you that 5 does not divide by 2 very well.
2: Compounding turbos is not necessary, there are dozens of turbo models that can supply more air than your engine could ever imagine of consuming.
3: VNT/VGT turbo technology has made twin turbos obsolete, old technology, and over complicated.
4: Space. The real estate is very valuable in a W123 engine compartment, especially when an intercooler is involved.
Twin turbo is impractical for a few reasons.
1: You have 5 cylinders, simple math will tell you that 5 does not divide by 2 very well.
2: Compounding turbos is not necessary, there are dozens of turbo models that can supply more air than your engine could ever imagine of consuming.
3: VNT/VGT turbo technology has made twin turbos obsolete, old technology, and over complicated.
4: Space. The real estate is very valuable in a W123 engine compartment, especially when an intercooler is involved.
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From: SFV CA
2008 Black Out C350 Saks Edition / 87 VW GTI
What are you after the wow factor or power?.....The injection pump may be a problem but there is a guy in Long Beach, CA that can answer about if the injection pump can provide for more boost--Dumars Diesel not sure on the spelling but he is the one..I asked him about this myself when I wanted to a 68 280SE coupe i had which uses a similiar injection pump, I don't remember his answer....but I must say you are a bit mad and I mean crazy and I do mean that in a nice way....
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Joined: Nov 2007
Posts: 4,433
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From: SFV CA
2008 Black Out C350 Saks Edition / 87 VW GTI
has any one done this or heard of someone who did. my car is like new in & out. w/105k mi. looking to make the all time cruser w/it. i am a ase cert. master mechanic. but have not heard of any one w act experince with this, and alltho i own a merc. i do not genrealy work on them. can you advence the pump? is there a bigger pump avable? injectors? wastegate mods? psi increase? any reply.
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MBWorld Fanatic!
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From: WNY
2005 w203 C230
The one in the picture I mocked up - and www.Wizardcooling.com welded up...I mocked up a second and that was welded up by my uncle...I changed pipe design and that one I could sell...
Thanks,
Jake
Thanks,
Jake
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From: Federal Heights, CO
1982 300D VNT, 1980 240D 3.0T, 1982 300TD
Actually they can't. They don't have a first clue about how to tune for our engines. Also, there is nothing to be gained by modifying the injectors of indirect injection engines.
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From: Terre Haute, IN
1983 mercedes-benz 300d
What makes you say that? Have you had experience with them? I'd like to know because they are doing my pump work and injectors. I know they have a lot of diesel experience in performance and seem pretty knowledgable. They upped my fuel flow on both the pump and injectors as well as upped the pressure so i can advance my pump.
Last edited by wlockerb; Oct 25, 2010 at 01:33 AM.
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From: Federal Heights, CO
1982 300D VNT, 1980 240D 3.0T, 1982 300TD
DI and IDI are cousins, not brothers
They have no experience with the Bosch MW pump, its RW governor or indirect injection diesels.
Experience with low-speed direct injection diesels does not translate over to high-speed IDI diesels. Its like comparing a PC to a MAC, similar in theory but very different in practice. Where the pickups make all their power down low, take tons of boost and don't like to be revved, the MB engines start to wake up at high rpms and don't take much boost.
Why? The stock injectors already flow freely enough to support 110hp/cylinder. All they'll do is kill drivability and increase emissions.
Direct injection injectors benefit from larger holes because the nozzle has to spray through multiple tiny orifices (usually 9 of them). Indirect injection injectors have no orifices so increasing their size only reduces atomization quality.
Increasing fuel pressure can be done by anybody with a 13mm wrench and pressure doesn't affect timing. The pump runs the same with 3psi of pressure as it does with 30psi.
Increasing pop pressure retards timing, so advancing your pump merely brings timing back to where it needs to be. Increasing pop pressure also has no effect on performance.
Sending the pump and injectors to Scheid will return you a maximum of 20hp, no matter what they do, because the stock pump simply can't pump any more fuel into the engine.
You could have gotten that 20hp for free (link) after about 2 hours work in your driveway removing the pump's fuel rack limiter.
The only way to significantly increase power is to replace the pump's 5.5mm elements with larger versions so more fuel can be injected safely.
I know they have a lot of diesel experience in performance and seem pretty knowledgable.
They upped my fuel flow on ... injectors
Direct injection injectors benefit from larger holes because the nozzle has to spray through multiple tiny orifices (usually 9 of them). Indirect injection injectors have no orifices so increasing their size only reduces atomization quality.
as well as upped the pressure so i can advance my pump.
Increasing pop pressure retards timing, so advancing your pump merely brings timing back to where it needs to be. Increasing pop pressure also has no effect on performance.
Sending the pump and injectors to Scheid will return you a maximum of 20hp, no matter what they do, because the stock pump simply can't pump any more fuel into the engine.
You could have gotten that 20hp for free (link) after about 2 hours work in your driveway removing the pump's fuel rack limiter.
The only way to significantly increase power is to replace the pump's 5.5mm elements with larger versions so more fuel can be injected safely.
Last edited by 240D 3.0T; Oct 25, 2010 at 04:00 AM.
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From: Terre Haute, IN
1983 mercedes-benz 300d
Hmm. so i wouldnt benefit at all from bigger nozzles? I was goin to go stock but they said it would cost like $100 more so i went with the performance ones. I am rebuilding the engine now so any help i could get would be appreciated. I trusted the info that they were giving me. I was also going to upgrade to a t3/t4 hybrid. Is this a bad idea? How much boost is to much with head studs? I just want more power. what will removing the fuel rack limitter give me? While i have you here I would like to ask another question. Will a 4 speed from a 79 240d work with my 300d? I have a donar car available.
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From: Federal Heights, CO
1982 300D VNT, 1980 240D 3.0T, 1982 300TD
No. The only thing you'll get is smoke.
Very. Spool up is much worse and trying to push more than 14psi of boost just makes it surge due to the engine's low volumetric efficiency. The stock turbo can handle everything the stock pump can give out.
When upgrading the turbo its best to stay away from the ancient T-series and KKK turbos. They're inefficient and have a narrow operating range.
The stock engine is good for upwards of 25psiboost.
20hp for short periods before the long injection duration makes the exhaust temperatures unsafe.
Yes.
Again, those are direct injection engines.
I was also going to upgrade to a t3/t4 hybrid. Is this a bad idea?
When upgrading the turbo its best to stay away from the ancient T-series and KKK turbos. They're inefficient and have a narrow operating range.
How much boost is to much with head studs?
I just want more power. what will removing the fuel rack limitter give me?
Will a 4 speed from a 79 240d work with my 300d? I have a donar car available.
Again, those are direct injection engines.
