Benefits of 205's vs. 215's on 300D?

[zachv]

I am now to the point of tire decisions and have a key question. What are pros/cons of these tire sizes. My goals are to get the RPM's down a little at cruising velocities, which the 215's would do, but does the fuel consumption go up with wider tires, and is 10mm of tire going to make a difference in performance on a non-perf oriented '85 300D Turbo? These will probably be going on 7" wide 15 hole original wheels or Tirerack replicas. Thanks for the help.

[Lee Scheeler]

Don't try to affect cruising RPM (hence gearing) with tires. To get them tall enough to reduce RPM's you would have to be beyond the 3% margin of variance from OEM RR and would risk severe rubbing/damage with a setup significantly taller.

If you want to improve fuel economy buy a tire that has lower rolling resistance than the ones you have on there now. The Michelin Energy MXV4 Plus is known for such traits. Also, run higher tire pressures than gascap. Keep the same ratio as listed on the gascap but increase the pressures of the tires to just beneath the "max cold psi" rating for that tire. Your ride quality will go down a bit but handling and fuel mileage should go up.

Hope this helps....Lee

[Chiragp]

Since your stock size is 195/70/14, I would stick with tires in the 24.75 area. If you try to lower RPM while adding a taller tire, you will end up rubbing and having computer errors, before you notice a difference in RPM while cruising.

As for recommendation, 205/60/15 (24.7) are a perfect match in tire size. I wouldn't consider 215/60/15 because they are 25.2". As far a tire, I would recommend something in a H-rated size because they have the best combo of handling and wear as well as noice and wet performance with All-Season capabilities.

If you want the best bang for buck, I know TirePro1 from Ebay is selling 3 sets of them, each set starting at $135 for all 4 with No Reserve. They say they are brand new and have the stickers on them, but Emial them with any question you might have about the product.
http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=319253635

If you are going to buy rims and tires, here is something I found on Ebay: http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=318571011

Just make sure to be careful, and not to get taken for a ride.

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Chirag (Charlie) Patel

- 99 Mercedes-Benx ML 430 V8 w/custom TV, Video, UHF, speaker system
- 93 190E 2.6 (4-sale) w/ an amp, equalizer, and CD-changer, integrated w. stock stereo for integrated cellular phone speaker system
- had a 93 190E m103 3.2, 5-speed trans,
- had a 88 300E 2.6
- had a 84 300TD w/275k+ miles
- 2001 C-Class - Maybe (if 190E sells)