I guess you could try to play defensively with the items. Also, make sure to go back to second if you see a CPU with a Blue Shell. I can't help out with the Kart combos, since I've used Mario on Standard everything to nearly three star every cup. I'm saving Mirror Leaf and Lightning Cups for when I am ready to get the Gold parts.
When you race, don't forget to drop into second place if a COM has a blue shell.
If a COM has lightning, try to stay on land as much as possible.
Always hold an item out behind you.
If you have a Mushroom or Super Star, hang onto those items. Use them only when jetting back into first place towards the end, or dodging lightning/blue shells.
Finally, remember to collect 10 coins each race. As for kart combos, you could try a heavier character for better speed and less jostling. And drafting is important, too! Don't try to pass a COM, stay right behind it until you achieve the draft and boost past it.
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I highly recommend using a lightweight. The rubberbanding reduces the effectiveness of a high speed rating. I like to use an acceleration of 3.75 or 4.75 in Grand Prix. In the Leaf Cup, I would reccommend using a good offroad rating. I think it's usually a good idea to sandbag with the first set of item boxes against the computers (I usually aim for about 5th place). The rubberbanding will make it easy to catch up to the higher positions without items.
Bent 00 posted...
Also, is there some place that details the best paths and kart combos to use for Time Trials?
I would recommend looking at super_luigi16's FAQ on this site.
It's probably unnecessary, but here's a link to it: http://www.gamefaqs.com/3ds/997822-mario-kart-7/faqs/63660
Rubberbanding is brutal in MK7. The best kart to use is a featherweight with high accel because the items will screw you over otherwise. Bumble-V is my personal choice since it has high accel and mini-turbo. As for wheels, you could go with any of sponge/standard/slick.
I'm assuming you've completed the other GPs if you're asking about those two specifically, so I won't go over all the basic crap for 3 star runs.
On a 3 star run, you really shouldn't be getting hit more than once per race (Or twice if you're unlucky), and so, Acceleration is going to be near-worthless, especially in offline GPs where you can get Mushrooms in first to instantly hit top speed again.
Metal Mario, Bruiser, Slick Wheels and any non-standard glider would be a good combo for completing it. If handling is an issue, then swap out the Slick wheels for Mushroom wheels.
As for the track specific tricks, just do all the usual stuff, take the inside where possible, play against ghosts in time trial, and so forth.
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