I'm about to start a rehab project entailing my 84 300SD and would like to go a certain route yet still be a daily driver. First off, The car has 316K on the odometer with the chain, guides, seals, and so on done by the previous owner as well as the driveshaft rubber discs. I just replaced the finger valves, transmission filter service, oil service and removed the air filter and installed a freeflow unit. She still is dog slow but I deal with it because this is my first diesel. Anyway.....

I want to do performance upgades along the line of:

• slightly bigger turbo with internal WG. Could the spring be replaced or the Internal WG be replaced for a stiffer unit to hold higher pressure?
• 2.75" exhaust pipe exiting right after the front wheel under the P/S door.

What do you guys recommend? I don't really care about noise as she'd be my ratrod style daily along with her new paint, suspension, and wheels....

Thanks,

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"Why operate within the law when you can operate above it?"

MB roster
'85 500SE euro Ratrod
'92 500E's x2 / '94 E500 stored
'91 560SEC w/43K stored
'92 Cabby 16V OE 2.1 AutoX car
JDM RHD cars now.

Contact me after Christmas.
You need more diagnosis before altering further.






Have a great day.

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1985 300SD
1983 300D
2003 Volvo V70

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There is no need for a bigger turbo unless you replace the injection pump with something that can flow more fuel. The stock turbo has the excess air available to burn everything a maxed out stock pump can flow (About 140hp at the crank). Look up "manual boost controller" and you will find what you should get.

There wouldn't be more than 1-2hp change since, other than the resonators on the SD, the stock 2.5" exhaust isn't very restrictive. I'd put a straight pipe in place of the resonator pair and be happy with the more aggressive tone. A 3' long straight pipe 1/4" bigger wouldn't be good for much other than noise.

But first, if its slow as you say, you have some issues that need to be corrected. What is your current 0-60 time and boost pressure?

Forced...welcome back my friend!

Just in time for Christmas!

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

..

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'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R

In a reply to vwbuge.... my diesel is quite slow... I will have to take it in to possibly have the Bowden cable adjusted as well as the valves. Hopefully that makes for a quicker ride..

__________________
"Why operate within the law when you can operate above it?"

MB roster
'85 500SE euro Ratrod
'92 500E's x2 / '94 E500 stored
'91 560SEC w/43K stored
'92 Cabby 16V OE 2.1 AutoX car
JDM RHD cars now.

I suggest you first look at the fuel delivery and the fuel dispersion efficiency.
If your injectors are not giving a nice pattern or your pintle and holes in the precombustion chamber are not in proper working order you can not hope to get the power the engine design is capable of.
This assumes valve setting, timing of the fuel delivery are proper, etc... all the usual maintenance things that can sneak up on us over the years because these engines are generally so dependable...

One option is



+

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1980 240d
1999 SL500

The diagnostic data you need for better performance/power is in these links..

Diesel Injection
Engine Mechanical
Fuel Delivery

I was going with the ALDA removal on the 300SD and wanted to know how easy is it to actually do? Most of the postings say that oyu just remove it and plug the pressure hose and that's it.. Is that all I really need to do?

__________________
"Why operate within the law when you can operate above it?"

MB roster
'85 500SE euro Ratrod
'92 500E's x2 / '94 E500 stored
'91 560SEC w/43K stored
'92 Cabby 16V OE 2.1 AutoX car
JDM RHD cars now.

forcefed44 have you done everything that whunter has recommended as far as routine things go like diesel purge and valve adjustment and diagnosing problems? Messing with the ALDA will do you very little good if there are serious things wrong on the car. Or you could make a current problem worse. Have you cleaned the ALDA? and a forum search should yeild all the answers to your ALDA questions.

Diesel purge, transmission svc, fuel filters, oil change, finger valves, vacuum line replacement, and CAI; done as the initial maintenance even when the PO did it previous to me buying it. Actually the body is going way before the engine, drivetrain, and suspension...

I cleaned the banjo bolt and line and that was not even dirty. The guy replaced the turbo with a reman fact unit. New IP, Chain, guides, new primer pump, fuel tank sending unit etc... Vacuum pump working.. transmission shifts clean...

The only thing I am leading to is the:

Valve adjustment
ALDA failure hence removal (more for performance)
stiffer boost actuator spring
exhaust system
custom cam grind
custom tubular turbo manifold and larger turbo
3" turbo back pipe

__________________
"Why operate within the law when you can operate above it?"

MB roster
'85 500SE euro Ratrod
'92 500E's x2 / '94 E500 stored
'91 560SEC w/43K stored
'92 Cabby 16V OE 2.1 AutoX car
JDM RHD cars now.

I would pop test your injectors, adjust throttle linkage, and do your IP timing before undertaking any of these steps (save valve adjustment, which is needed anyhow).

As others have said, modifying the exhaust system won't do much except give you a louder exhaust.
A larger turbo is not necessary unless you change/modify the IP. A manual boost controller is much cheaper, easier and more predictable. You will get noticable results by upping the boost to the existing turbo. But making sure everything already on the car is working well (injection system, air and turbo intake, throttle linkage) is needed first.

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WOW..... Add me to the ALDA-less gambit.. I just removed my ALDA unit and checked all the visuals as in vacuum hoses and lines. I plugged the port from the ALDA to the Freq Valve.. Let me just say..... Offboost acceleration is austounding... Diesel wise (Was hoping for 70's GM Fishbowl bus black soot) The shifts from the transmission are like my 380's smooth... Pre removal the car was like my friends 240D 5 speed..... even with the 5 speed was slow.. Now I'm quite happy.. Next onto the mods and valve adj....

Intake tract. I have installed a CAI instead of the stock and I love the spooling sound of the turbo.. ala my turbo gassers

Manual boost controler: Where do you guys recommend an optimal place to plumb that in as well as a boost gauge?

Thanks guys!!! Happy New Year.....

__________________
"Why operate within the law when you can operate above it?"

MB roster
'85 500SE euro Ratrod
'92 500E's x2 / '94 E500 stored
'91 560SEC w/43K stored
'92 Cabby 16V OE 2.1 AutoX car
JDM RHD cars now.

FYI, that is a HOT air intake. It does nothing but make more noise, the stock filter was not a restriction.