Looking to buy spare tire (Not full size) for 300D - PeachParts Mercedes-Benz Forum

#1 06-27-2002, 11:07 PM

Hi All,

I have a 1984 300D turbodiesel and as you all know, it weighs and drives like a tank. So I am looking to lessen the weight of my car so that the performance and gas mileage will go up.

I have a full size spare tire in my trunk and I am thinking about replacing it with a smaller size spare to save weight. Do any of you know where I can purchase a smaller size spare tire, either from the Internet, or stores or you know someone is selling one.

Also, I would like to know if there are any parts on this 300D that I can get rid of or replace with lighter weight parts to further lessen the weight of this car.

I know that some of you will convince me to keep the full size spare and that there are no parts that can be replaced with lighter parts. I see this coming, but I am sure there are smaller and lighter spare tires for my 300D and that some parts on this tank can be eliminated or replaced.

Any and all comments will be greatly appreciated.

Holson Adi · #2 06-27-2002, 11:14 PM

I really can't think of much. The engine itself seems pretty damn heavy. The injection pump itself is heavy!!@#!@#!

As for the spare... maybe you could try to find a lightweight spare from a newer model Benz or from the dealer. Otherwise just carry one of those 'fix-a-flat' stuff.

Lighter wheels maybe?

Definitely can't thinkof much without making compromises.

If you wanna go to the extreme... you could try fabricating aluminum hood and trunk. Try retrofitting one of those funky ceramic brakes from the CL55 F1 Edition.

Ridge · #3 06-28-2002, 01:35 AM

Simon,

As they say in New York, "Forget about it!!!

I can't invite you over this weekend, because my son is down in L.A. But what you really need is a transmission transplant. Junk the automatic and go 4 speed manual. You won't believe it's the same car. In fact, as you may have already seen, we'll soon be putting our first 5 speed manual in a turbo. About the same time well have installed what may be the first ever intercooler on a 5 cylinder turbo motor. Should add about 21-24 HP. But if you really want to pump your turbo up, put one of the propane injection units on it. Adds an immediate 40% just by flicking a switch. That addition alone would give you 48 more HP, totaling 148 HP!!!!!!!!!!!!!! Imagine 48Plus and a 4 or 5 speed. It boolges the mind. The add 21 more with intercooler for 169HP. Now go Flowmaster exhaust and you've 179HP!!!!!!!!!!!!!!!!!

I live just over in Fremont, so I'll give you a blast when the manual turbo is back in town. So you can see why I advise, forget the spare.

Ben

Ridge · #4 06-28-2002, 01:40 AM

Silly me! I got so excited about my new 5 speed my math went all to hell. 120 Normal HP + 48=168+21=189+10=199. Right? Should embarass a lot of Rice Rockets. Imagine them seeing you pull away belching diesel smoke!!
Ben

omegabenz · #5 06-28-2002, 04:21 AM

Save weight...

loose your interior

AMG wheels are really heavy, so avoid those. Except the 3 piece, and those are expensive, and plus they will fit probably only sls and 500Es.

why dont you just "forget a'''bout it"? And throw your spare tire in the trash. You got tripple A (AAA) right? I took out my 14" spare and put a 17" wheel for my car in it.

See I have a coupe though, so its lighter already.

why dont you just take the tires off and just drive around on the rims, they are cheap enough anyway.

lol. I am kidding.

I have some E430 copy rims, they are really light with the mxv4 michelins in 195/65/r15. Your mileage will go up because your tire rolling diameter decreases.

Those 16" rims that I posted for sale are pretty light too. Check those out.

Seriously the interior of your benz probably weights like 500 lbs.

Take out the back seat there are only three bolts. It takes me like five minutes to tear out theback seat. Get rid of the passenger seat too.

Take out your engine and replace it with a 500 euro aluminum block engine, it will be lighter than the diesel...oh wait you wanted fuel economy =).

Maybe you should take out the headlights. Those are like 30 lbs, euro light are like 45 lbs. Take out your washer bottle, thats 8 lbs. Lower your car, that will get rid of some of the spring weight.

Take out all the trunk liners you know the plastic ones in the trunk. Those are about 20 lbs. Take off the cowl covers, those are 2 lbs.

take out the instrument cluster, thats 10 lbs, but plug the oil pressure line because I would hate to see a mess like that. Take out the windows and then put in some cardboard and duct tape them on.

Take off the doors, and then weld some sheet metal on your car, then you can jump in your car like the dukes of hazard. THat would be pretty cool.

Get skinny tires, and avoid low profile because those have a lot of rubber to stay stiff on the sidewalls.

I think if you follow my recommendations you could put your car on a diet and loose about 1000 lbs.

Let me know what you try,

Austin

#6 06-28-2002, 07:49 AM

What you need are all the aluminum parts from the 240D factory racer.

Have a great day,

#7 06-28-2002, 11:50 AM

Hi All,

I appreciate receiving all your comments except for the one about turning my car into the Dukes of Hazard's car. That's ridiculous. Wouldn't be a Mercedes then, would it? No, it would be a piece of #*$% !

But I think LarryBible may have something there about the aluminum parts for the engine. Larry, where can I purchase these? How much are they? Are these aluminum parts custom made?

As for the spare tire problem, I may have found a solution. I'll probably just go to the junk yard and pick up a mini-spare with a five bolt pattern that fits the 300D and try it on for size. I think some of those spares should be able to fit the 300D.

With regard to lightening up the 300D, I think modifying the engine or transmission is a good thought and would be one way to obtain high performance. But the cost is lower gas mileage, which is something I did not want to trade against. Aside from tearing out the seats, instrument panels, etc., I thought about taking out parts I did not need. You need the seats, instruments panels, etc. but I thought, what about the AC compressor? That like weights like one of an elephant's legs, right? Besides, I rarely use it and the darn thing never works. So, out it goes!

Aside from the AC compressor, I just can't think of any other part to take out without being the new Duke of Hazard county. Unless someone out there, like perhaps LarryBible carry aftermarket lightweight aluminum parts and can help me out to the goodies?

Simon

Ridge · #8 06-28-2002, 01:28 PM

Simon,

If you really want to lighten up your '84, you must be aware that the 300DT fuel tanks hold approximately 22 Gallons, whereas the 240D fuel tanks hold only 16 Gallons. Gasoline, (can't remember diesel spec.) weighs in at 6 pounds per gallon. So if you use3d the 240 tank, which bolts right it even when full you'd be 36 pounds lighter.

Before you make any decisions on expensive aluminum parts that might not give you anything like what you're looking for, you might want to drive a manual turbo that's just across the bay.

By the way, intercooling a turbo generally gives several benefits: 1. Lower combustion chamber temperatures giving longer engine durability.
2. Fuel economy goes up from 4-7% provided you're not flooring it all the time.
3. You get more power, 18%-22%, at highway speeds where the incoming charge is cooled the most.

To date, our intercooler installation is being done without drilling any new holes into the frame or sheet metal, which we find important. We've had to alter one a/c hose length but that's it for the moment.

Ben

omegabenz · #9 06-28-2002, 02:12 PM

ben,

do you make intercooler kits? Do you have them for sale? Do you have any pictures? Cost?

My dad will spend thousands of dollars to increase mpg by 1mpg, eventhough it will take him 4 years to burn that much diesel by the amount of money he spend. Don't spend too much money on something that doesnt mean that much.

The best recommendation would be switch your car to maunal because you save the weight and you can fine tune which gear you should be in.

Austin

stephenson · #10 06-28-2002, 02:15 PM

It is supposed to be a tank ...

If you would combine all the ideas, perhaps it would be something other than on the margin ... however, even adding up 20% of the ideas would still end up on the margin.

#11 06-28-2002, 02:23 PM

My comment about the factory racer was a joke. The 240D is one of the slowest cars known to mankind ( I say that with much love for the breed.) I don't think there was ever too much effort toward trying to make one win any races.

If you're serious about trimming weight by changing fuel tanks, wouldn't it just be easier to fill it to no more than 16 gallons?

Have a great day,

Holson Adi · #12 06-28-2002, 02:25 PM

The A/C is a good idea. If you don't need it, it doesn't work, and you don't wanna fix, and you wanna keep it for long, take the whole thing out.

Maybe if the sunroof is broken, take the mechanism out too.(every little bit counts right)

I honestly don't feel much a difference when my car is running with a full tank of fuel and with the warning light on.

That intercooler sounds interesting indeed...

JoelS · #13 06-28-2002, 03:37 PM

...to try and convince you to keep the full-size spare. One of the appealing things about these cars is that they DO have a real spare tire. I hate the pissant small tires that substitute for real rubber. I've had to use one on my pickup truck several times and it's only a very temporary fix. I wouldn't want to be several hundred miles from home and have to limp back on one.

Sure you'll save some weight, but like some of the other options presented - and some were quite amusing - it's not in keeping with this car's nature. If you really want a hot rod, get one and keep the CD for cruising down the highway or driving relaxed. I'd love to have something to bury my foot in but neither your car nor mine is gonna be a sports car. They're too heavy and have a relatively low power engine but as a result they get good gas mileage and ride well on the open road. I enjoy driving my car, even often pretending that it's a sports car, but it'll never be anything other than a cruiser.

By the way, Ben Ridge may be my hero. I wish I could afford to put a 5 speed in my car...not for performance benefits, of course...

Maybe we could start a list of possible cheap hotrod candidates for use when the urge to drive fast hits us? BMW 2002 for handling and pep or flat-out US muscle car for rubber burning fun?

Best to all,

Joel

Ridge · #14 06-28-2002, 04:13 PM

megabenz,

There is a distinct probability that we will develope a minimum kit for the intercooler with a set of detailed instructions. As an example, the actual intercooler that we're using is one out of a Ford Mustang SVO and happens to be the same one recommended by Spearco Intercoolers for a diesel up to 4 liters displacement. So one might either get their intercooler at the junkyard or order from Spearco and save around $500.00 on it. So one has the choice of doing it cheaply but with some sweat equity.

There would be several things that one would have to purchase for the kit. 1. As you'll eventually see we've made a very nice induction setup channeling air into the intercooler. 2. Since one needs to relocate the a/c dryer slightly, you'd also need a slightly longer a/c hose leading from the condenser to the dryer. 3. A new dryer mount. 4. A plate to relocate the heater electric pump and hose to connect it in the new location. 5. Tubing from turbocharger to the intercooler and back to the intake manifold.

The whole thing is shaping up to be a neat, tidy and maybe even attractive installation. So far we've managed to do everything without even drilling any holes in the actual car sheet metal or frame. All of which means one could convert it back to original or move it to another car without anyone even knowing.

We do have to sacrifice a headlight assembly but they are very easy and cheap to come by. We bring the cool air in through the left side fog light area but put a chrome grill over the opening on both sides so it's not too obvious.

Anyway, we'll put up pixs and specifications once it's running. My son is resisting my suggestion that we take it to the drags to get some real times on it, especially since we could compare it against another one that we have that is at present stock, with automatic, etc. Every now and then one has to do something crazy to add spice!!

Ben

omegabenz · #15 06-29-2002, 12:11 AM

Hey Ben,

Check your email.

To all,

I am going to put a 17" spare in my trunk. I know my car is slow, but it gets 27 mpg. I have loaded my car with junk, it still gets 27 mpg around town, so I am not going to try to lower the weight. I just upgraded to 17" today.

I have AMG aero I with Michelin Pilot Sport A/S in 235/45/ZR17, yes that's ZR17. I find that the ride is even better than my 195/65/R15 MXV4 michelins. I am very impressed by the A/S tires.

I would like to try the intercooler. I had a mitsubishi eclipse one, but I just sold it to some kid. It didnt look like I could fit it anywhere.

See you,

Austin