rosscarlson Posted September 9, 2009 Share Posted September 9, 2009 Guys, I have thw Whiteline sways with Perrin endlinks. I've tracked my car 7-8 times this season and am very comfortable with he she feels on the track. While not perfect yet I'm really enjoying how well she handles (I've already done rims, tires, BBK, Coilovers). My Whitelines are adjustable and both are set in the softest setting. Am I right that tightening the rear will stiffen it up possibly resulting in understeer? I'm heading to the track Friday/Saturday so I can play with the settings a bit. But tonight is my only night to make the adjustments. I've read through the forums so I'm just looking for confirmation that I'm right... -Ross Link to comment Share on other sites More sharing options...
aigochamaloh Posted September 10, 2009 Share Posted September 10, 2009 Tightening up the rear (or going a bigger size in the RSB) will usually result in more oversteer, not understeer. Hence, going bigger in FSB or stiffening it up will result in understeer. Link to comment Share on other sites More sharing options...
wpmarky Posted September 10, 2009 Share Posted September 10, 2009 +1, stiffer rear = more oversteer Link to comment Share on other sites More sharing options...
integroid Posted September 10, 2009 Share Posted September 10, 2009 +2 run the rear stiff and the front soft and it should create some oversteer. My car understeers with both front and rear stiff with whitelines. Link to comment Share on other sites More sharing options...
rosscarlson Posted September 10, 2009 Author Share Posted September 10, 2009 Thanks guys, that's just what I thought. I'll have all my tools with me at the track so I can adjust between sessions if I want but I'll get some open lap time on Friday and I wanted to set it how I think I'll want it before then. Don't want to be playing too much while at the track! -Ross Link to comment Share on other sites More sharing options...
BAC5.2 Posted September 10, 2009 Share Posted September 10, 2009 Before doing a stiff rear bar, I'd do a huge front bar. You'd be surprised what the car can handle like with a REAL alignment (by a race shop, not by Sears. Not all alignments are created equal!) and a big front bar. There are 3 rules for Subaru handling. 1) Caster is your friend. There is no such thing as too much in a Subaru. 2) Big front bars help the car rotate when YOU want it too. Rear bars limit rear grip, and oversteer when the tires want too. 3) Alignment. Alignment. Alignment. The three most important words to making a Subaru handle well. Get a real alignment. [URL="http://legacygt.com/forums/showthread.php/proper-flip-key-interesti-159894.html"]Flip Key Development Thread[/URL] "Genius may have its limitations, but stupidity is not thus handicapped." - E. Hubbard Link to comment Share on other sites More sharing options...
rosscarlson Posted September 10, 2009 Author Share Posted September 10, 2009 BAC5.2, Thanks for the input. I've already done the largest Whiteline front bar, same for the rear. I've also had a full corner balance and alignment from one of the Subie tuners here in Boulder (there are so many Subies here there are some really good shops). So I already did all that at the beginning of the season. Right now the car is very balanced, just a bit of understeer at the limit. Since oversteer is a bit more fun I figured I'd adjust for just a bit of it... -Ross Link to comment Share on other sites More sharing options...
SubyShop.com Posted September 10, 2009 Share Posted September 10, 2009 You can also adjust the coilover spring rates or damping to change the suspension balance. Most people don't like swapping springs, so stiffening up the damping in the rear can make the car tend to oversteer more. Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted September 10, 2009 Share Posted September 10, 2009 We've been moving away from super huge front bars, especially for track cars. They really help turn in, quick transitions, and they keep the rear end on the ground...so they're nice for auto-x. But steady state corners and corner exit we've been happy with other set-ups. A bigger rear bar increases front grip to add oversteer. They don't just take away rear grip. Alignment is HUGE. EDIT: where are you noticing your understeer? entry, exit, steady state? all of the above? - Andrew Link to comment Share on other sites More sharing options...
rosscarlson Posted September 10, 2009 Author Share Posted September 10, 2009 Thanks for the input guys. RaceComp - I'm mostly seeing understeer during steady state or exit. One of the tracks I frequent has a section where your hard right, then left, then a VERY brief straight before braking. If I get a bit wobbly before that braking zone as I enter the next quick right I've done a few 4 wheel drifts through it (which are a blast). I just don't want to make the car wobble to get some oversteer, a little is fun. I think I'll set my rear bar to stiff and play with the dampening in the front at the track that day. I've had the sways at soft and the dampening (front and rear) and stiffest. -Ross Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted September 10, 2009 Share Posted September 10, 2009 stiffening the bar will help steady state and exit. the dampers don't have much of an affect on steady state, but softening front rebound will help exit. - andrew Link to comment Share on other sites More sharing options...
rosscarlson Posted September 10, 2009 Author Share Posted September 10, 2009 Thanks for the advice Andrew - I'm hitting the track tomorrow and Saturday so I'll post back with how it all comes out... -Ross Link to comment Share on other sites More sharing options...
Dirtrace95 Posted September 11, 2009 Share Posted September 11, 2009 Before doing a stiff rear bar, I'd do a huge front bar. You'd be surprised what the car can handle like with a REAL alignment (by a race shop, not by Sears. Not all alignments are created equal!) and a big front bar. There are 3 rules for Subaru handling. 1) Caster is your friend. There is no such thing as too much in a Subaru. 2) Big front bars help the car rotate when YOU want it too. Rear bars limit rear grip, and oversteer when the tires want too. 3) Alignment. Alignment. Alignment. The three most important words to making a Subaru handle well. Get a real alignment. I dont get why guys put such huge bars in the rear, Yes it makes the car stay flat... but you can only go so far then the grip gets bad and around you go. That would really be bad in winter conditions. For a daily driver that you still like to drive hard here n there I wouldnt go with anything bigger than the JDM 20mm or in my case I used a 19mm Rallitek. The suspenstion has to stay some what limber in the rear to work. A big bar makes it too ridgid. My 2 cents:rolleyes: Link to comment Share on other sites More sharing options...
rosscarlson Posted September 13, 2009 Author Share Posted September 13, 2009 Dirtrace95 - what you're not getting is I track my car all the time, 8 days this year alone (and I've only got 6k miles on it). So I want my car as flat and balanced as I can possibly get. I generally drive in the fastest groups (Lotus, 911's, M3, etc) so I have to be able to keep up with them, and keep up I can (and generally can get around most). It's so much fun to have a stunned Lotus drive come up and ask me what the hell I'm driving and how the hell a Subaru sedan passed them. Yeah, I like that. Back to the tread - well I tightened the rear bar and lowered the dampening in the front, neither helped that much. I'm getting slightly less understeer now but still virtually no oversteer. I know that getting an AWD car to oversteer is tough, so far the only thing I've found is by trail braking into a corner, if I do that on an off camber corner I'll get the back to come around a bit, but that's not the "right" way to do it. Next weekend I think I'll play with my tire pressures a bit to see what I can gain there... Any other advice is appreciated... -Ross Link to comment Share on other sites More sharing options...
wpmarky Posted September 14, 2009 Share Posted September 14, 2009 Might be due to the same size bars. You could try to add the AVO reinforcement brackets to the rear sway bar mounts, I hear those help stiffen it up even more. Or you could try is maybe trying a different set of sway bars to get you the balance you're looking for, or maybe just getting a beefier rear or downgrading the front. Since you track often, you probly already tried upping the rear tire pressures. How fast are the turns you're taking where you're getting understeer? Link to comment Share on other sites More sharing options...
rosscarlson Posted September 14, 2009 Author Share Posted September 14, 2009 I've already done the AVO rear reinforcement brackets so I'm set there. I don't want to change things enough to swap to a different set of sways, really I do like the way it handles a lot, it's just that a little oversteer is a bit more fun. I haven't played a ton yet with tire pressures, that's on my list for my next day. As for speed it depends, anywhere from 75mph (a few fast sweepers) to more like 55mph (some of the slghtly tighter stuff). -Ross Link to comment Share on other sites More sharing options...
GTTuner Posted September 14, 2009 Share Posted September 14, 2009 I have Perrin 22's. I had the front on stiff and rear on soft. This weekend I moved the rear bar to stiff, loving it. Car feels so much more neutral. Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted September 14, 2009 Share Posted September 14, 2009 What is your alignment set at? What are your spring rates? These are the first things to look at. - Andrew Link to comment Share on other sites More sharing options...
SubyShop.com Posted September 14, 2009 Share Posted September 14, 2009 ^^^^ With the multi-link rear on the Legacy, you might need a much stiffer spring than what you have now in the rear if you want the car to be more loose. -Franz Link to comment Share on other sites More sharing options...
Dirtrace95 Posted September 14, 2009 Share Posted September 14, 2009 Dirtrace95 - what you're not getting is I track my car all the time, 8 days this year alone (and I've only got 6k miles on it). So I want my car as flat and balanced as I can possibly get. I generally drive in the fastest groups (Lotus, 911's, M3, etc) so I have to be able to keep up with them, and keep up I can (and generally can get around most). It's so much fun to have a stunned Lotus drive come up and ask me what the hell I'm driving and how the hell a Subaru sedan passed them. Yeah, I like that. Back to the tread - well I tightened the rear bar and lowered the dampening in the front, neither helped that much. I'm getting slightly less understeer now but still virtually no oversteer. I know that getting an AWD car to oversteer is tough, so far the only thing I've found is by trail braking into a corner, if I do that on an off camber corner I'll get the back to come around a bit, but that's not the "right" way to do it. Next weekend I think I'll play with my tire pressures a bit to see what I can gain there... Any other advice is appreciated... -Ross When we want to make our sprint car oversteer we use front shocks with a lower compression rate and a higher rebound rate. When turning in it lets the weight transfer to the front.. or "dive in " going into the corner. The stiffer rebound holds the weight longer and lets the rear stay looser. Might be something to try ??? Link to comment Share on other sites More sharing options...
rosscarlson Posted September 14, 2009 Author Share Posted September 14, 2009 Good suggestions all - a few answers: my alignment is -1.5 degree camber in the front (is that what you mean) and as for spring rates I can't remember right now, VERY stiff front and rear. So stiff that I can't even get the car to shake by grabbing the fender and jumping up and down (seriously). So stiff that I think my teeth my fall out. I guess next I'll soften the front a bit as I agree that I'm probably just too stiff up there. I've got 3 more track days this season to play with it then I'll be setting up for winter stuff... -Ross Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted September 14, 2009 Share Posted September 14, 2009 You won't be able to get it to oversteer with just -1.5 degrees negative camber up front. I think we need more detail. Exact spring rates are very important. - Andrew Link to comment Share on other sites More sharing options...
rosscarlson Posted September 14, 2009 Author Share Posted September 14, 2009 You got it - I've got the sheet at home from the align and corner balance to I'll swipe it and post back... Link to comment Share on other sites More sharing options...
wpmarky Posted September 14, 2009 Share Posted September 14, 2009 Someone please correct me if I'm wrong, but it's my understanding that the front needs to roll at least a little bit to induce oversteer so that the body can twist and rotate through the turn while maintaining grip. Either that, or the other way is by trying to make your rear lose grip sooner so the tail slides around. On a side note, I switched from Rallitek springs to STI Pinks, and could feel the slight return of understeer due to increased stiffness in the front springs, or is it just my head? Link to comment Share on other sites More sharing options...
Drew888 Posted September 14, 2009 Share Posted September 14, 2009 Not knowing Ross's finer detail can you describe a general suspension configuration that 'would' allow what he's asking for? Curious... [URL="http://legacygt.com/forums/vbpicgallery.php?do=view&g=1586"VbGallery/URL] Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.