1smoothsedan

Hello Everyone.

I am the proud new owner of a '85 300sd. I am looking to do some performance modifications. Any suggestions?? I already have a air intake and am looking to put in a strait piped exhaust. This is a daily driver and runs on veggie oil and im looking to get a little more power out of it. Any advice is greatly appreciated.

Thanks!

johnshasteen

congratulations!!My wife has an 82 300SD that she has been driving since new - she loves it and at least once a week someone asks her if she wants to sell it. All we've done over the years to hers is to change to 15" '86 wheels and replaced the back seat with the one with head rests - now it looks like an 86 or 87.
On yours, the air intake is an okay idea, but Ithe factory system is probably designed for the right amount of back pressure for the Turbo - check with an expert on diesel turbos before you change the exhaust.

240D 3.0T

If your intake is a "cold air" intake, get rid of it. It actually draws hot air from behind the radiator. Straight pipe exhaust won't do anything but make the car much louder.

Check out this forum, specifically the forum named "Superturbo": http://schumanautomotive.com/forums/

1smoothsedan

thanks for your responces. i checked out that link and found alot of reading. i am trying to find a new exhaust system. my original is rusted and is not in great condition. i figure why not upgrade if i already have to replace. i was thinking a strait pipe just because of cost, but if thats not a good idea do you have any recomendations on performance exhausts for our cars.

240D 3.0T

There are no "aftermarket" exhaust systems made for our cars that I know of. The only options are to buy OEM or make it from scratch. I'd recommend going with 2.5" pipe. 3" makes it difficult to route the pipe to the stock location (The reason I have mine setup as a side exit before the rear wheel) and our engines don't flow enough exhaust to make good use of a 3" pipe.

There is no problem with going straight pipe, I have for 4 years. There is just no significant benefit to offset the additional "noise" level. If you can live with the exhaust volume then go for a straight pipe. If not, avoid "chamber" style mufflers like flowmaster. If you look through one end of the muffler and can't see light at the other, it will be too restrictive.

Some muffler shops should be able to make you an exhaust system from the down pipe connection (by the transmission) to the exhaust tip for about $100 without a muffler. Ask for mandrel bent exhaust pipe instead of the traditional crush bent pipes.

Mandrel:


Crush:

1smoothsedan

what about disconecting the waste gate for more boost? should i worry about blowing the turbo?

240D 3.0T

HIGHLY NOT recommended. More boost will not get you any more power until you have turned up the full load adjustment.

I suggest you adjust the turbo up to stock pressure (13psi) with this method: http://www.serenitysys.com/MB/Servic...617_turbo_.htm
Any more boost than 13psi without adjusting your fuel rate will just add extra heat to the intake air and reduce efficiency.

Before you tune it to anything beyond stock specifications, I suggest you install an exhaust gas temperature (EGT/Pyrometer) gauge to monitor your engine. It will let you keep an eye on temperatures to prevent the melting of the engine.

harkgar

240:

Is there a EGT gauge in the later MB diesels like my 2006 CDi? I do not want to see my engine turning into mashmellow. I read in Diesel Truck that this device is installed in many diesel trucks. There are lots of plug and play hand held devices with claims of 100 + horse power and torque increases, plus exhaust braking systems. Pity they do not do anything like those for the MB diesels.

240D 3.0T

Nope. An EGT gauge isn't installed in your CDI. You would have to get one installed.