HE351 Turbo/ 98 300TD - PeachParts Mercedes-Benz Forum

Sleek~Sliver602 · #1 01-25-2015, 08:06 PM

So ive been doing some reading and the fact that the turbo thats factory on a the 300td is so small and a hy35 or hx35 is a better turbo. well the HE351 is the best of both worlds. so im wondering on a stock 1998 300td with the stage 2 chip can this engine spool either one of the 3 i mentioned or do you need alot more fuel? also will it hurt Mpgs alot?

A common thing used in the cummins world on the older engines to keep things cool is water/meth along with getting some lower end TQ out of it. can this or has this been used on these before?
the Trans in the car what is that good to handle? I dont want to make this another project i just want the motor to breath nicely and get what i can from stock fuel with out blowing the trans up. i dont plan on beating the car to death just want the power there when i need it.

Im having to sell my cummins

so i figure go back to were i was and buy another benz

Sleek~Sliver602 · #2 01-25-2015, 09:05 PM

Well with further reading I have seen that the previous 3 are much to big. a GT2359V or 2559v would be a good one to go with. I so alot of talk about a VNT/VGT turbo and using the ECM WG control signal to work the vanes but I cant find alot of info on how it was done. does anyone have this info?

capflya · #3 01-26-2015, 12:56 PM

Holset 35 (HX/HY/HE) is too big for a stock or even chipped 606. You need a built IP to spool one of those properly, even a variable vane turbo.

Get an HX30 and it should be pretty decent. VVT's are nice but a good amount of work to get going. Vacuum controlled vanes are common to take place of the electronics but still tricky to get right.

HE341ve might work but I forget the specs on it right now.

capflya · #4 01-26-2015, 12:57 PM

Also.. if you don't have the car yet maybe get an E320 CDI from 05/06? They've got the power you want and get good MPG. A friend of mine has one and he gets ~40mpg avg, 70-80% highway miles.

KarTek · #5 01-26-2015, 05:01 PM

You can get maybe 225 HP with the stock pump but you're really stretching the injection event out so far that you get smoke and high EGT's.

You really need a 7 or 7.5mm pump and then go with a bigger turbo. This will give you an honest 300 HP. More if you get a bigger turbo or go compound.

winmutt · #6 01-27-2015, 04:45 PM

Don't forget the rest of the drivetrain. I've replaced everything behind the engine, multiple times now...

Sleek~Sliver602 · #7 01-27-2015, 06:04 PM

Well Im looking into this car as it is all i can afford at the moment. The trans I can rebuild myself and get a better TQ converter. what can be done to the Rear end?? Im not planing on making this thing a race car just want something that is peppy. I have read though that water/meth works nicely so I will probably do that with the stage 2 chip and be done.

I was told the car im looking at may have a faulty injector is the injector the same to pull as a om602? or is it easier/harder? specialty tools needed?

Thanks for the replies guys I appreciate it.

Sleek~Sliver602 · #8 01-27-2015, 07:40 PM

Does anyone know what the smallest twin scroll turbo there is out there. to bring an idea from the gas world and sled trucks( some not all) a diverter valve can take a 72mm twin scroll turbine and spool it almost twice as fast because you send all the exhaust in one floute in the exhaust housing and when your wanted psi is reached it opens to let the engine breath.

KarTek · #9 01-27-2015, 08:55 PM

A few answers and a few things to think about:

The stock exhaust manifold has a funky triangular turbo mounting flange so pretty much any other turbo will need some sort of adapter.

My '98 stock would do 0-60 in about 8.5 seconds. Not a super fast car but that's pretty quick and it pulls hard to over 100. A chip could make it even better with the stock turbo.

The 606 has a hemi head so the injectors are in the top under the plastic cover as opposed to the 603. You'll need a 22mm deep well injector socket and they're not difficult to remove. You also have to keep in mind that crud falls into the injector well and you need to make sure it doesn't fall into the pre-chamber.

Sleek~Sliver602 · #10 01-27-2015, 09:43 PM

Ya Im aware of the Manifold i was planing for my diverter valve to be where i would make the adaptor. Thanks for the info on the injectors. I work on big diesels and I know most of all that but honestly dont know much about IDIs and I had remember reading about the 2.5td I had in my 190D if you pulled the injectors you needed to do the heat shields or something thats why I asked.

KarTek · #11 01-28-2015, 06:52 AM

You always need to do the heat shields. I have a small hand full around for the times I remove injectors.

With the 606, you'll have to fashion a little hook out of stiff wire to fish the shield out of the well after you remove the injector.

Sleek~Sliver602 · #12 01-28-2015, 08:48 AM

Ok cool. Well I spoke with a gentleman in texas that is big into performance parts and designs for the p pump found on a 12v cummins and told him the market is small but a om606 can make good power and there is a decent amount of guys that I'm sure would love to open it up. He said he's in only reason is the fins are the only place to get parts and if I recall one person stateside?? Thought I could add another.

On a different note the transmission is a 722.6 obviously and trans go makes a shift kit for these. Is that something that is a good idea especially with 191 on the clock? Also can the newer version be used in this model car say from a e55 and just swap the valve body??

Sleek~Sliver602 · #13 01-28-2015, 09:11 AM

Also if I get to say 300 hp can the rearend handle that? Can the stock trans handle that?

Cloudsurfer · #14 04-01-2015, 06:52 PM

I'd like to get to an honest 300HP with mine too, and had planned on a 6-speed manual swap and likely E55 LSD in the rear.

If your guy can start figuring out how to make OM606's make power and keep the computer happy, I think there'd be a decent bit of interest.

KarTek · #15 04-01-2015, 09:48 PM

Quote:

Originally Posted by Cloudsurfer

If your guy can start figuring out how to make OM606's make power and keep the computer happy, I think there'd be a decent bit of interest.

That's no problem. I'm running 7.5mm elements with no mods to the computer and it runs happily along with no codes on the stock turbo.

Once I get the bigger turbo installed, it's just a matter of running a boost regulator on the MAP line so it doesn't trigger an over boost code. I have the same setup on my truck and the most boost the ECU sees is 17# when the turbo is pushing far more.