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Old 01-09-2020, 04:39 AM   #337
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That is what I would expect with that change in tire for your car. You need more negative camber in front. RCE Yellows will help overall but more camber would make a very good difference.

- Andrew
More camber should fix the understeer, great, how about the rest of the problems?
Everyone seems to agree that too much grip overwhelm the stock suspension, my question is basically if changing only the springs will make a meaningful difference or I should save the money and go straight to coilovers?
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Old 01-09-2020, 04:57 AM   #338
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Depends on tires. If you run street/hybrid tires of closer to stock size and not of very low threadwear (thinking of PSS grip level), it's not as if stock suspension is unusable and not as if changing out springs or coilovers will improve one's laptimes lot. Very same money spent to improve driver himself will net more return
And you mentioned 10 trackdays/season .. that sounds to me more then sufficient amount to switch to track oriented/dedicated alignment, as that's were most of wear will happen. -1.2 front camber seems insufficient for that, and while intended -2.2 a bit better, but i'd aim for at least -3 (and rear -2.5). Thus suggesting to buy in addition to those powerflex bushings also Pedders eccentric topmounts (if you want less NVH issues vs camberplates), or if budget tight, another camberbolt set for other strut hole (but would prefer pedders topmount + powerflex bushing + single set of camberbolts. I had sheared once camberbolt head, for piece of mind would like one of bolts stock full strength).
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Old 01-09-2020, 07:29 AM   #339
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Depends on tires. If you run street/hybrid tires of closer to stock size and not of very low threadwear (thinking of PSS grip level), it's not as if stock suspension is unusable and not as if changing out springs or coilovers will improve one's laptimes lot. Very same money spent to improve driver himself will net more return
And you mentioned 10 trackdays/season .. that sounds to me more then sufficient amount to switch to track oriented/dedicated alignment, as that's were most of wear will happen. -1.2 front camber seems insufficient for that, and while intended -2.2 a bit better, but i'd aim for at least -3 (and rear -2.5). Thus suggesting to buy in addition to those powerflex bushings also Pedders eccentric topmounts (if you want less NVH issues vs camberplates), or if budget tight, another camberbolt set for other strut hole (but would prefer pedders topmount + powerflex bushing + single set of camberbolts. I had sheared once camberbolt head, for piece of mind would like one of bolts stock full strength).
Lowering springs are also adding negative camber, I might even get enough on both ends with this single mod (might need LCAs though). Is there any other reason I should go Pedders route instead? (LCAs will be mandatory in this case)
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Old 01-09-2020, 08:14 AM   #340
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More camber should fix the understeer, great, how about the rest of the problems?
Everyone seems to agree that too much grip overwhelm the stock suspension, my question is basically if changing only the springs will make a meaningful difference or I should save the money and go straight to coilovers?
FWIW, I tracked my car for a year on a 2015 stock suspension with RCE springs and was quite happy with it. It did make a big difference IMO.

The following year I got as good deal on some Ohlins and got a really good alignment. Can't recall specs atm. It made a world of difference and the car was really smooth.

I wouldn't skip doing the springs and still have them. If I stop tracking the car I will put the RCE and stock struts back on and sell the coils.

I like to do things in smaller steps to learn as I go. I would recommend the springs and move on from there at a later date. They're not expensive and it's a good learning experience.
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Old 01-09-2020, 08:31 AM   #341
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biggie: lowering doesn't add "enough", at least if one doesn't overlower, which in turn may cause other issues with geometry/handling/susp. travel & compliance.
For example, for front i seen dual camberbolt sets maxed out at around -2.3 at stock height, if added reasonable lowering to that, IIRC maxing out will be at around -2.5 camber. There might be more extra camber gained from lowering at rear though, but not sure, as never considered lowering myself.
And why LCAs are mandatory in Pedders topmounts case? Rear LCAs are most common means to gain camber adjustment in rear on these cars. Pedder eccentric topmounts are meant for front, as one of means of extra camber with less NVH compromises vs pillowball camberplates.
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Old 01-09-2020, 09:01 AM   #342
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And why LCAs are mandatory in Pedders topmounts case? Rear LCAs are most common means to gain camber adjustment in rear on these cars. Pedder eccentric topmounts are meant for front, as one of means of extra camber with less NVH compromises vs pillowball camberplates.
You recommended negative camber in the back as well. If I go with lowering springs I'll get "some" camber in the front as well as in the back, so I might not need LCAs. If I go with Pedders (only) then rear LCAs are mandatory to change the camber since Pedders are front top mounts...

From what I've read in this topic people got -1 to -2 camber in the back using lowering springs so I was hoping for around -1.5 you recommended (I know there's a big chance there will be significant difference left/right). Same logic goes for the front, current -1.2 plus whatever I get from lowering might push the camber close to my target (more than -2).

I realize now that with a small drop (1" max) I might get way less than I was hoping in both front/back

Just like @new2subaru I like going in small steps, so I think I'll try powerflex bush first and go from there (with LCA next on the list...I'll need these anyway when I'll switch to coilovers).
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Old 01-09-2020, 10:24 AM   #343
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More camber should fix the understeer, great, how about the rest of the problems?
Everyone seems to agree that too much grip overwhelm the stock suspension, my question is basically if changing only the springs will make a meaningful difference or I should save the money and go straight to coilovers?
The springs will help. see @new2subaru.

With sticky tires, coilovers will be better (as long as they're good coilovers) but the RCE yellows still work well even with the Federals.

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Old 01-09-2020, 10:42 AM   #344
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"Pedders only", just like "powerflex bushings alone" are worth only for partial of needed camber, around 0.75deg IIRC each. Even more so, if powerflex bushings are adjustable, pedders topmounts are of fixed offset. So i just use combo of three on front, pedders+powerflex (at maxed out position)+single set of camberbolts, doing actual adjustment only with camberbolts (from eg. -3 for summer track to -1.5 for winter).

As for drop, i really suggest not to drop any more then 1", even if there are both coilovers and springs for lowering even more in market. Problems being like there already being relatively short bump travel on these cars even stock, thus lowering, even with cut bumpstops will leave too little and will need very stiff springs (bye bye comfort for dual used car), stock ground clearance also not exactly plentiful (hello diagonal crabwalks over speedbumps, steep driveways and digging in snow), geometry will be fscked up (so more parts/budget needed to compensate, eg. for roll center change), due higher angle rear CV joints will see much higher wear (so another purchase to rise diff advisable). So in short - better don't . Reasonable drop = less spendings, better handling, better comfort and compliance . Only thing gained with slamming too much - arguably better looks in eyes of few who whines about wheel gap and alike, and not caring making anything else worse. If you track your car, if you still use it for daily driving, then i guess that you care enough for both handling and comfort to not sacrifice those for sake of slamming.
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Old 01-09-2020, 12:01 PM   #345
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Slamming/lowering is not my target, I'm just exploring options to fix my ride so I'm not going to do anything (including dropping) if I don't have a valid reason (function >>> form for me). I also have back problems, so I'm not willing to compromise to much on comfort.

I would switch to RCE yellows in order to fix my issues (not to lower the car) but only if that fixes my problems (without creating others).

Even with coilovers I will not drop more than 20mm (if at all).
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Old 01-09-2020, 02:52 PM   #346
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If you're just trying to eliminate the understeer, I wouldn't go straight to lowering springs unless you're going to pair it with rear LCA's to dial out a little camber. I'd look at ways to get more front camber first and go from there.

If you have clearance at the tire and spring seat, you can run SPC lobed bolts in the lower holes of the front knuckle with the stock lower bolts in the top hole, you should be able to get over -2* of camber up front, probably closer to -2.5*. If you don't have enough clearance, you can also run camber plates on the stock shocks/springs.

There is VERY minimal camber gain on the front suspension, so lowering it alone won't get you any more useful camber up front. The rear camber gain is much better, but as a result you'll have even more of a grip imbalance.

You could also try a rear sway bar, but it wouldn't be my first option.
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