kleggo Posted April 19, 2006 Share Posted April 19, 2006 Yes, i did search and i did read the FAQs which had lottsa good info, but not specifically what i'm looking for. now that that's out of the way I'm buying aftermarket wheels / tires for my 06 LL Beanie. It's my understanding that with the AWD, i should maintain nearly the same Effective Wheel / Tire Diameters at all four corners to keep things happy. My question is, how far from the nominal diameter of the existing wheel / tire combo can i deviate as far as the AWD system is concerned? I'm looking to fill the wheelwells a bit more without lowering the car. I realize that changing EWD may effect tire / body clearance and speedo reading. thanks Craig Link to comment Share on other sites More sharing options...
robinlsb Posted April 20, 2006 Share Posted April 20, 2006 Huh? Do you mean change all four corners to larger ewd? If so then it won't affect the AWD. It will chage the braking characteristics or the car thou. "Belief does not make truth. Evidence makes truth. And belief does not make evidence." Link to comment Share on other sites More sharing options...
kleggo Posted April 20, 2006 Author Share Posted April 20, 2006 Huh? Do you mean change all four corners to larger ewd? If so then it won't affect the AWD. It will chage the braking characteristics or the car thou. ___________________________________________________________________ yes, as i wrote above It's my understanding that with the AWD, i should maintain nearly the same Effective Wheel / Tire Diameters at all four corners to keep things happy. my question remains. how much larger can i go before the AWD drive or any associated sensors freak out? i know that wheelwell opening size limits EWD. So does a 1 or 2" increase screw with the AWD sensors? be safe kleggo Link to comment Share on other sites More sharing options...
schwinn Posted April 20, 2006 Share Posted April 20, 2006 It's not a matter of freaking out sensors... it's that the AWD differential (front-to-rear one) will be in constant slip. Not sure how this would affect it's longevity... As for ABS, it won't care, for the most part... it looks for wheel stoppage, so a slight speed difference won't confuse it. Why are you changing only one pair of wheels to larger? Link to comment Share on other sites More sharing options...
SC GT Posted April 20, 2006 Share Posted April 20, 2006 I'm running 225/45/18s in an LGT sedan, slightly lowered (Bilstein Spec B struts and STi pink springs), +50 offset rims, with no problems. I got them because I prefer 18s to 17s aesthetically, but I wanted to put a little more tire between my wheels and the road than I would with 225/40/18s. And they do fill out the wheel wells nicely. Link to comment Share on other sites More sharing options...
kleggo Posted April 20, 2006 Author Share Posted April 20, 2006 It's not a matter of freaking out sensors... it's that the AWD differential (front-to-rear one) will be in constant slip. Not sure how this would affect it's longevity... As for ABS, it won't care, for the most part... it looks for wheel stoppage, so a slight speed difference won't confuse it. Why are you changing only one pair of wheels to larger? ___________________________________________________________________ hmmmmmmmmmmmm i guess i'm not writing as clearly in my old age as i thought. I will be changing all four wheels / tires and all four will be the same diameter. thank you Link to comment Share on other sites More sharing options...
azca Posted April 21, 2006 Share Posted April 21, 2006 don't go from 16" to 22" and you will be fine, j/k ___________________________________________________________________ hmmmmmmmmmmmm i guess i'm not writing as clearly in my old age as i thought. I will be changing all four wheels / tires and all four will be the same diameter. thank you Link to comment Share on other sites More sharing options...
Xenonk Posted April 21, 2006 Share Posted April 21, 2006 actually, the car comes with already 25.6" tall tires.. I would like to see if you can even cram in a 29" tire.. you wont clear the spring perch nor the fenders anyways.. so really, you'll bump into fitment issues WAY before of you bumping into any of the issues you are even bringing up in this thread. Carry on. Keefe Link to comment Share on other sites More sharing options...
robinlsb Posted April 21, 2006 Share Posted April 21, 2006 Keefe is a racer, I suggest you check Stoptechs website and do your own calculations. Everything will be affected, the only question is how much wiggle room is available in the ABS/EBD/ traction control units. Inches at 100 FPS add up! The Hub sensors will not be affected, but they will report the wheel speed incorrectly to the ECU(s). "Belief does not make truth. Evidence makes truth. And belief does not make evidence." Link to comment Share on other sites More sharing options...
Xenonk Posted April 22, 2006 Share Posted April 22, 2006 Keefe is a racer, I suggest you check Stoptechs website and do your own calculations. Everything will be affected, the only question is how much wiggle room is available in the ABS/EBD/ traction control units. Inches at 100 FPS add up! The Hub sensors will not be affected, but they will report the wheel speed incorrectly to the ECU(s). did i miss something here? I mentioned that he'll have a fitment issue WAY before the electrical issue.. in other words, the electronic wont read anything because the tire cant fit on the car. Keefe Link to comment Share on other sites More sharing options...
robinlsb Posted April 22, 2006 Share Posted April 22, 2006 did i miss something here? I mentioned that he'll have a fitment issue WAY before the electrical issue.. in other words, the electronic wont read anything because the tire cant fit on the car. I don't think you missed anything. My comment was that any change in the total distance traveled with one revolution of the tire MAY affect the ABS/EBD/ETC funtions of the car. It all depends on how flexible the coding is. On the STI/Impreza platform its pretty robust. On the Legacy, who knows? "Belief does not make truth. Evidence makes truth. And belief does not make evidence." Link to comment Share on other sites More sharing options...
Xenonk Posted April 23, 2006 Share Posted April 23, 2006 I don't think you missed anything. My comment was that any change in the total distance traveled with one revolution of the tire MAY affect the ABS/EBD/ETC funtions of the car. It all depends on how flexible the coding is. On the STI/Impreza platform its pretty robust. On the Legacy, who knows? well, I can safely say, it's ok, it's a pretty wide range (heck, we have viscous LSDs, it'll take some spin from the tires to get the LSD to kick into effect). I have slapped plenty of different sizes on the GT already (from 24.2" tall to 25.7" tall tires), and the ABS and ECU can deal with the small change, the difference of rpms and vehicle speed that the ECU sees is definitely tolerable for the coding/programming to handle. Keefe Link to comment Share on other sites More sharing options...
f1anatic Posted April 23, 2006 Share Posted April 23, 2006 So running the next bigger tires 225-45-R17 on stock rims will not cause any problems ! Link to comment Share on other sites More sharing options...
robinlsb Posted April 23, 2006 Share Posted April 23, 2006 It's not a matter of freaking out sensors... it's that the AWD differential (front-to-rear one) will be in constant slip. Not sure how this would affect it's longevity... As for ABS, it won't care, for the most part... it looks for wheel stoppage, so a slight speed difference won't confuse it. Why are you changing only one pair of wheels to larger? ABS does NOT look for wheel stoppage! It looks for impending lock up based on wheel speed changes compared to a ton of coder defined variables. In addition, EBD also rears its ugly head here. The LGT has NO brake proportioning valves. Brake bias is controlled within the ABS and G sensor. "Belief does not make truth. Evidence makes truth. And belief does not make evidence." Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.