1984 300SD with a MANUAL TRANSMISSION - PeachParts Mercedes-Benz Forum

Twizted · #1 09-11-2006, 11:48 AM

I've got an '84 126 300SD with a 671.951 motor.
It's got a four speed Manual Transmission (fabricated to fit).
I've put intake and propane injection on it.
It's got other small modifications to help with performance (ie: alda, turbo switch, wastegate, bypassed vac. regulator, etc...)

This car is very fast.
I haven't gotten out to the track yet, but I'm able to beat many cars on the street.

What do you think this car is worth?

Currently, the speedometer does not work (I have to put the pickup on something [like the driveshaft]).
The fuel gauge does not work (sending unit is probably bad).
The clear coat is peeling on the front of the car (hood and right fender).

The cosmetics never really mattered to me on this car (I've got my '83 to mess around with that), but if I were to sell it, I might do a few things...

Anyway, since this car was never made with this transmission (aside from Taxis in Germany), I thought that maybe some people had input on the value of this car.

Brian Carlton · #2 09-11-2006, 12:16 PM

That's a tough call.

Clearly you've done quite a bit of mods to it for speed. However, most folks who purchase such a vehicle do it for durability.........the speed is secondary.

You'll have to wait for the person who really is appreciative of what you've accomplished and has a use for such a vehicle.

Additionally, with the body in marginal condition, the price will be negatively affected.

pawoSD · #3 09-11-2006, 12:22 PM

Sounds like a cool car!

I just upped my boost pressure to 13-14psi with a clamp do-dad that I made, wow, improvement! My alda is max'd, I still get no black smoke so I think I may try shimming it at some point.

With those simple changes I have noticed a substantial improvement in acceleration, it really takes off now! I leave people behind at lights all the time....

Twizted · #4 09-11-2006, 12:25 PM

My black one ('83 with auto) is pussing an average of 22 PSI boost.
I haven't hooked up a boost gauge in the manual yet.
But the propane solenoid kicks open at about 4 PSI, and that's about 2 miles an hour in both cars...

pawoSD · #5 09-11-2006, 12:37 PM

Quote:

Originally Posted by Twizted

My black one ('83 with auto) is pussing an average of 22 PSI boost.
I haven't hooked up a boost gauge in the manual yet.
But the propane solenoid kicks open at about 4 PSI, and that's about 2 miles an hour in both cars...

Does it have an intercooler or EGT gauge? You could easily melt pistons in the engine pushing it like that without proper accomodations....it has happened before....

I didn't know the stock turbo's were capable of that much boost! wow...though when I clamped my wastegate hose shut I did see mine spike to 15psi before the overboost valve kicked in.....

Then I adjusted it down to about 13psi.

Brian Carlton · #6 09-11-2006, 12:43 PM

Quote:

Originally Posted by pawoSD

With those simple changes I have noticed a substantial improvement in acceleration, it really takes off now! I leave people behind at lights all the time....

You ever get an accurate 0-60 time with it??

Twizted · #7 09-11-2006, 12:47 PM

Well, the propane drops the engine temp quite a bit...
I have an intercooler, and was going to put in on the black one, but never got around to it.

I didn't "pinch" my waste gate hose, I simply plugged it.

That small plug (on top of the intake manifold) is unplugged (allowing the turbo to spool full speed).

I've bypassed that vaccum regulator (in front of the fuse box).

I've had the black one running like this for close to two years now.

I also run a German repair shop here in Sac - www.lbgermancar.com

My current plans are to get the grey one (manual) a little faster.
I may put the intercooler on it with a Co2 spray or maybe isoprenaline injection in addition to the propane.

pawoSD · #8 09-11-2006, 12:58 PM

Whats the 0-60 time??? I also am curious!

Brian Carlton · #9 09-11-2006, 01:00 PM

Quote:

Originally Posted by pawoSD

Whats the 0-60 time??? I also am curious!

I was curious about yours!

Twizted · #10 09-11-2006, 01:13 PM

Well pawoSD, if you're curious about mine...

I haven't gotten a 0-60 time in the grey one because currently the speedometer isn't working.
I've got the pickup, and I need to put it on the driveshaft, but after the tranny swap, I haven't had a speedo.

As far as the black one, I don't have a 0-60 time, but in the 1/4 mile, it pulled a mid 15 second.
I think the last time I had it out at the track I pulled a 15.6x
That was with the trunk loaded with over 150lbs of speakers...
I've since then changed my system, and no longer have the AudioBahns.

I used to have two 12" AudioBahn AWISD-12s (50lbs each).
Now I have a JL-W7 (it's a little bit lighter), and the box is much lighter too!

Boardmonger · #11 09-11-2006, 03:44 PM

Dang that 83 is pretty dang nice. I really like those rims on there, a classic and agressive look. I'd also like to hear to 0-60 times when you get them, its probably pretty quick.

bgkast · #12 09-11-2006, 03:51 PM

Anymore details on your propane system?

What's the deal with the Blow off valve? I thought they were unnecessary on diesels because there is no throttle butterfly valve to close and cause a build up of pressure.

Twizted · #13 09-11-2006, 04:28 PM

heh - you're right...
That BOV isn't on this car anymore.
It's been moved to a WRX.

What would you like to know about the propane?
I'm thinking about making kits and putting them on ebay.
The Bully Dog and PowerShot 2000 kits are WAY too expensive.
I used my other solenoid on my grey one ('84 M/T) so I don't have a full kit right now, but I've got everything else...

bgkast · #14 09-11-2006, 05:53 PM

I was just wondering about the basic system configuration. The only other propane system I have seen on a Mercedes was a guy that used a BBQ tank in the back seat with a hose running to the air cleaner.

diametricalbenz · #15 09-11-2006, 06:33 PM

Where did you source the 4 speed manual? Is it from a 240D?