I saw a picture of me going through a turn and the inside rear wheel was 4-5 inches off the ground. It is a tight turn (Sebring/hairpin) but doesn't have any big bumps. Is this an indication of a poor setup on my car?
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I saw a picture of me going through a turn and the inside rear wheel was 4-5 inches off the ground. It is a tight turn (Sebring/hairpin) but doesn't have any big bumps. Is this an indication of a poor setup on my car?
No. It's an indication of a FWD setup.
And soft front springs.
Not really. I've run 1300# front springs on the Integra and still lift the rear tire. That's because I was running 2000# rear springs and a solid rear bar (no, not any more).
FWD race cars will lift the rear tire, regardless of front spring rate. It's normal.
It's nothing to worry about. You want those front tires on the ground all the time. You just need one (outside) rear tire on the ground at some point.
Not sure you can "tune" the rear lift without adversely affecting something else.
Tricycles don't corner as well as go karts. Porsches lift front tires and oversteer like MFs when the front to rear springing and sway bars aren't correct. Keeping all four on the track is important. We don't lift a rear tire on the Type R we run in the enduro races.
FWD needs the rear tire up about 3 in or less. If it is on the ground, that weight(30#+) is not transferred to the inside front tire.
It is a tick faster. Enouhg so that I have reduced the rear springs and added rear bar.
Creating a tricycle.
AKA "going faster in a FWD car."
Been doing it for three decades, dude. Gotta trust us on this one...Fiestas (and Golfs, and Integras, and Neons) ain't RWD, rear-engined Porsches.
But I encourage you to investigate, develop, and test the world's best-handling FWD car while working to keep both rear tires on the ground. Make it work and the world will beat a path to your door.
I wish you the best in your endeavors.
For the rest of us non-super-humans...lifting the rear tire is perfectly normal.
GA, who recognizes the rear tires on a FWD car have two basic, primordial purposes: keeping the gas tank from sparking on the ground, and making it look better on the used-car lot. And no, I didn't make that up myself, someone a lot smarter did...
Yep... Well tuned FWD cars will always end up lifting a rear wheel. How much/how far that rear wheels lifts is indicative of total front grip and roll rate. Personally, I've found the fastest setup (and coincidentally easiest to drive also) has limited rear wheel lift. Is it there? Sure. Is it a foot in the air? Nope.
The FWD race car is limited by dynamic loading of the outside front tire. Anything that can reduce this loading will allow higher turn speeds. That is why the inside tire needs to be a little up.
Controlling the inside rear tire; you can lower the tire with wider track on the rear, wheel spacers as little as 10mm wil have some effect.
Accounting for the driver! Most LHD race cars will lift the right rear tire more than the left. Toe out the LR tire 3mm or more so that the dynamic weights are closer to even, yes the car dog tracks a little, yes it may go faster.
Raise spring rate and lower sway bar rate.
The farther outside the rear tire tracks than the front tire , the more weight is balanced front to rear and thus has a higher overall all speed potential, more equal tire loadings etc.
This is one reason why ¨dynamic rear steer¨ goes faster, less front tire load/more rear tire load.
I believe go karts have chassis flex built into them, and this is tuned, to create inside rear tire lift/unloading during cornering. Without that the kart will push like a dump truck.Quote:
Originally Posted by callard
Tricycles also have only one FRONT wheel and completely unrelated cg issues, so the metaphor is completely invalid. Not to mention big wheels corner faster than traditional tricycles.
+1 to not a bad thing to lift the rear tire a bit.
Attachment 3642 Happens to all of us.
Can get around the "problem" and save on tire bills.....just put a big caster under the rear bumper.
Well that's pretty much all the rear tires on a FWD car are..
They're also good at smoking out anybody directly behind them when they lock the inside rear on trail braking..
I use the rear as spare tire holders for old worn-out, cycled-out Hoosiers.
There are even lower budget options...Quote:
Originally Posted by Greg Amy
http://clunkbucket.com/wp-content/ga...te-race-06.jpg
That's what I used to do. It certainly helps control the tire costs!Quote:
Originally Posted by Greg Amy