turbo/non-turbo advice - PeachParts Mercedes-Benz Forum

kerry · #1 08-10-2002, 11:08 AM

I own a 77 300d (non-turbo) which I am quite happy with apart from the fact that it's carrying capacity is somewhat limited. I do a lot of canoeing and carry a lot of camping gear along with a couple of boats so I am looking for a 300TD. I'm looking at a 1980 TD at the moment that is in good condition with relatively low miles, but it does not have a turbo. Given the fact that I will be carrying a lot of gear in the vehicle, should I pass on this one and wait for a turbo version?? How much difference does that turbo make? Can someone who has experience with both offer some advice? By the way, I live in Colorado so altitude is a factor.

leathermang · #2 08-10-2002, 12:26 PM

I suspect you would be much happier with a turbo. Even with a turbo , at some speeds the acceleration is not exactly blinding

But the altitude deal would really be helped by the turbo...

Ridge · #3 08-10-2002, 12:27 PM

Kerry,

Before deciding on the 300TD, you might want to find out what the rear end ratio is. On the 300TD turbos the rear end ratio is higher than the regular 300DT sednas. That means they do well on the flats but are less able on the hills when compared with the turbo sedan. If the same holds true for the non-turbo you could be even less able in the mountains. The normal rear end ratio in the 300D sedans is 3.46. Turbo sedans are 3.07 and a local MBZ owner's 300DT is 2.88.

Obviously, you want something around the 3.46, a 3.96 like the 280E would be even better but not up in the 2.99 range. Hope this helps.

Ben

leathermang · #4 08-10-2002, 12:40 PM

If you determine that a combination which would be helped by a 1979 300td (NON turbo) rear end would be useful I will sell you the one out from under my parts car... and if you need a beautiful dark blue almost perfect interior I don't need that either...

I used to own a 1981 turbo wagon... once the turbo kicked in it would really fly...but going from 20 to 40 was pretty slow...

In comparing the two and all the axle ratios available... keep in mind that the difference between the 3.46 and the 3.07 is only about one seventh ... whereas the difference between turbo and not is between 88 ?hp and 120... a factor of nearly one half....

The 3.46 rear end with the turbo might be just the combo you are needing for the carrying/altitude combo you have described....

I am a little surprised that Ben did not try to sell you on putting a manual into the wagon... a turbo/3.46rear/5speed manual would be about the perfect machine.... Greg

Ridge · #5 08-10-2002, 06:22 PM

Greg,

You're right I didn't try to talk him into a manual 4 or 5 speed but then I don't want to get type cast. If you put the 3.46 rear end ratio in a 300 turbo you have a problem not chripping the tires in all the lower gears. Not to mention snapping your passengers necks. They complain mightly. In short it's been tried and isn't altogether successful.

Now! Put a manual 4 speed in the thing so you don't have to have invitations made to cross intersections or climb a hill!!!!!!!! Greg will give you all the particulars.

Back in form.

Ben

leathermang · #6 08-10-2002, 10:19 PM

Ben,Well, the four speed sure is easier to find...but I was assuming that the 5 speed was an overdrive 5th... thus taking some of the fuel mileage penalty off the change to the 3.46 axle...but retaining the low end... Is the 5th gear not an overdrive ratio ?

What?, you have done 4 or 5 or more change overs to manual trans.... I think it is a little late to avoid typecasting...

kerry · #7 08-10-2002, 11:17 PM

Thanks for all the advice. I'll probably pass on the non-turbo. (although I'm still not certain. I'm checking on the gear ratio). Of course, if I could find a 5 speed I wouldn't have to think twice about buying that. I have a 307d motorhome (in the UK) with the 616 non-turbo engine and 5 speed and I love it although it wouldn't be much good in the Rockies.
What year was the first year for the Turbo in the Wagon? A dealer told be 82 but I'm sure I've seen ads for 81's with turbos?

william rogers · #8 08-11-2002, 02:30 AM

Sure would go with the turbo,Iv'e played around with many different combinations on the modulator and bowden cable and got my 81SD so thats it shifts where I want it to and the shifts are not too harsh.I now consider it a quick car in nearly all siuations.It actually feels as quick up to 50 as my Euro 500SE though I know it's not I also have a custom 2wd Blazer with a warmed up 454 so am used to quick cars........
William Rogers.....

leathermang · #9 08-11-2002, 08:03 AM

The "first year for" may be dependant on whether you are talking about the year it was sold or the "model year". My 1981 300td had a turbo , but I think it was manufactured in oct or nov... which may have made it a 1982 for model year purposes...

In the factory shop manuals, and in parts manuals it will say " to serial number ___________" etc....to distinguish parts and design changes...

kerry · #10 08-30-2002, 12:31 PM

Bought a turbo. Wow, what a difference at this altitude. I had to check under the hood to make sure there was a second engine mounted in there! No doubt, turbo is the way to go. The non-turbo feels as though you have to push it to its limits all the time whereas the turbo feels as though there is a thoroughbred racer under tha hood constantly itching to be unleashed.