rear end doesn't feel planted
02-20-2012, 09:28 PM
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rear end doesn't feel planted So, my rear tires were nearly burned up, so I got some used tires (to get me through the school year). Unfortunately, all the tire shop had was 275/35/18 F1 summer tires 
. Anyways, now my rear end feels less planted than ever.
Obviously, tires are part of this... but when i go to buy new tires, what tires should I get to help my car feel more planted?
What suspension mods help with this?
Does anyone else have this issue? It is extremely annoying, because on perfectly smooth roads it handles great, whereas any sort of bumps, the rear end gets thrown around like a rag doll.
. Anyways, now my rear end feels less planted than ever. Obviously, tires are part of this... but when i go to buy new tires, what tires should I get to help my car feel more planted?
What suspension mods help with this?
Does anyone else have this issue? It is extremely annoying, because on perfectly smooth roads it handles great, whereas any sort of bumps, the rear end gets thrown around like a rag doll.
Last edited by hatched91; 02-22-2012 at 12:16 PM.
02-20-2012, 09:55 PM
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When I would run bikes on the road course I dealt a lot with tire temps, much more than I have with car temps. Keep in mind...
You have a smaller side wall height. Though you have a larger contact area your side wall isn't giving like the stock size so you aren't going to get as much flex as you did, therefore creating less contact with the ground when hitting bumper, potholes, etc. also, you now have a summer performance tire which may be optimized for higher performing temps and doesn't work well on cold ground (don't know where you're located and what the temps are).
You have a smaller side wall height. Though you have a larger contact area your side wall isn't giving like the stock size so you aren't going to get as much flex as you did, therefore creating less contact with the ground when hitting bumper, potholes, etc. also, you now have a summer performance tire which may be optimized for higher performing temps and doesn't work well on cold ground (don't know where you're located and what the temps are).
02-20-2012, 10:11 PM
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The eagle F1's are 275/35/18, and the old tires were yokohama avid W4S 245/45/18. I should emphasize that even with the old tires, it still hopped around bumps pretty badly. Just wondering what type of tire may help this, and what others have done to get around this. My old bmw stg 2 540 was much, much more planted, hands down.
02-21-2012, 04:23 PM
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Nobody has issues with their back ends hopping around? I do feel like something is loose in the rear end, and my diff bushing and subframe bushings have been replaced. Maybe whatever is loose in the rear end is causing issues.
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02-21-2012, 06:14 PM
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If you're running 275s on a stock 8.5 rim, on most tires (some tires runner wider/skinnier than others), you're going to have significantly more squirm under lateral loads, due to the mismatched tire/rim width pairing.
02-21-2012, 06:28 PM
#10
If you're running 245/45/18 in the front and 275/35/18 in the back, your suspension has to be totally out of balance right about now because of the difference in your wheels' outer diameter. The thing that doesn't make sense is that it sounds like you're complaining about oversteer, when in reality, a staggered setup like that should promote understeer.
02-21-2012, 09:02 PM
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agreed, 275s are not ideal on 8.5" rims. I noticed a difference and I don't like it, I'll either get the rear rims widened or go with a stickier stock size tire next time.
02-22-2012, 12:40 AM
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275/40's are within half a millimeter of 245/45...275/35 are 27.5mm's shorter than 245/45..not ideal.
I've been running 275/40's on the back for a year and love them. If by "hopping around" you mean wheel hop, then yes every V has that problem
I've been running 275/40's on the back for a year and love them. If by "hopping around" you mean wheel hop, then yes every V has that problem
02-22-2012, 12:20 PM
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I think you guys are missing my point. I should have probably never brought up my current tires, because it's just causing confusion.
The tires i have had are Yokohama W4S 245/45/18. The problem is that my car is not stable around corners. It tends to hop around a lot over bumps in the road, especially bumps in corners.
What make and model tire would be most beneficial in cornering on the street? I.e. where inconsistiencies are always present in the road.
What type of suspension mods would help increase stability in cornering?
The tires i have had are Yokohama W4S 245/45/18. The problem is that my car is not stable around corners. It tends to hop around a lot over bumps in the road, especially bumps in corners.
What make and model tire would be most beneficial in cornering on the street? I.e. where inconsistiencies are always present in the road.
What type of suspension mods would help increase stability in cornering?
02-22-2012, 06:19 PM
#14
Sounds like one of your rear shocks is bad. I had the rebound on each of my rear QA1's adjusted differently on accident once and it acted exactly as you describe. It squirmed horribly and When I would hit a bump around a corner the rear would jump over about a quarter lane.
02-24-2012, 10:14 AM
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I looked underneath my car, and saw that the passenger rear shock looked like it had some scarring on the lower part of the tube, whereas the drives did not. I will pull the shock off tomorrow. Hopefully that is the issue!
02-26-2012, 12:28 AM
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I really do not think it's seized. I just pulled the lower bolt out to see if it was blown, and I couldn't get it to move with some pressure from one arm, while laying under the car.
02-27-2012, 01:23 PM
#20
J/K... sort of... - it needs to move... add some force and make sure it rebounds after you let go.