How much pressure to make a Falken lose grip?
08-26-2003, 04:25 AM
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How much pressure to make a Falken lose grip?
For whatever reason, I have the worlds only 7th gen Celica that understeers...
Basic question, with a Falken, just how much pressure does it take to make it lose grip? I've run as high as 50 psi rear and 38 front, but I still can't get it to come around without excessive efforts (heavy trail braking, or big lifts), I want it to be subtle.
60 psi, 70 psi? There has to be a point where I've got dangerous levels of air in the tire...
Scott
Basic question, with a Falken, just how much pressure does it take to make it lose grip? I've run as high as 50 psi rear and 38 front, but I still can't get it to come around without excessive efforts (heavy trail braking, or big lifts), I want it to be subtle.
60 psi, 70 psi? There has to be a point where I've got dangerous levels of air in the tire...
Scott
08-26-2003, 04:39 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
i've gone as high as 70psi and the tire didn't blow up. i was definitely nervous though. how much rear camber/toe-in are you running? that is likely your problem, not tire pressure.
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08-26-2003, 04:48 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
Wouldn't a lower pressure in rear lend itself towards oversteer?
I run 43f/31r and my car rotates like a top.
I run 43f/31r and my car rotates like a top.
08-26-2003, 04:50 AM
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Re: How much pressure to make a Falken lose grip? (solo-x)
I'm trying to keep teh alignment as is (for now) because tire wear is good. Back when I was on Hoosiers, I could add 5 pounds to the rear and it was like being in a different car, the problem is the Falkens, the front sjust don't generate enough grip...
Front: -2 degrees camber, 0 toe
Rear: -1.4 degrees camber, 0 toe (the 0 toes is considered agressive in the Celica camp)
Shocks, Koni SA all around.
Right now, I'm looking for a bandaid for a problem, next season I'll either be back on real tires with better (DA) shocks, or in a different car. I'm just playing this season on the Falkens to save money (2 drivers every event, 2 events per month, 1.5 sets of tires for the season).
I could add a little toe out and all would be well, even a little more negative camber would loosen the rear (yes, more does loosen the rear, you never get the whole tire on the ground with more rear camber).
Scott
Front: -2 degrees camber, 0 toe
Rear: -1.4 degrees camber, 0 toe (the 0 toes is considered agressive in the Celica camp)
Shocks, Koni SA all around.
Right now, I'm looking for a bandaid for a problem, next season I'll either be back on real tires with better (DA) shocks, or in a different car. I'm just playing this season on the Falkens to save money (2 drivers every event, 2 events per month, 1.5 sets of tires for the season).
I could add a little toe out and all would be well, even a little more negative camber would loosen the rear (yes, more does loosen the rear, you never get the whole tire on the ground with more rear camber).
Scott
08-26-2003, 05:10 AM
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Re: How much pressure to make a Falken lose grip? (89STS)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 89STS »</TD></TR><TR><TD CLASS="quote">Wouldn't a lower pressure in rear lend itself towards oversteer?
I run 43f/31r and my car rotates like a top.</TD></TR></TABLE>
In my simple world, raising tire pressure is like raising spring rate, with the appropriate effects. What you say might be true past a certain threshold though...
I run 35 all around with my Integra with stock suspension, which makes it a bit tail-happy in fast corners
I run 43f/31r and my car rotates like a top.</TD></TR></TABLE>
In my simple world, raising tire pressure is like raising spring rate, with the appropriate effects. What you say might be true past a certain threshold though...
I run 35 all around with my Integra with stock suspension, which makes it a bit tail-happy in fast corners
08-26-2003, 05:35 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
Falkens behave opposite of hoosiers. You need to lower pressure in the rear to get rotation.
Everyone tries some ungodly high pressures in the rear with those tires and that just doesn't work. Set the falkens down to around 25-28psi and have fun rotating.
Everyone tries some ungodly high pressures in the rear with those tires and that just doesn't work. Set the falkens down to around 25-28psi and have fun rotating.
08-26-2003, 06:43 AM
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Re: How much pressure to make a Falken lose grip? (Todd00)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Falkens behave opposite of hoosiers. You need to lower pressure in the rear to get rotation.</TD></TR></TABLE>
See, that's the kind of stuff I like to hear. I'll give it a shot. Kind of like the old BFG R1 days. Just keep lowering the presure untill the *inside* of the tire cords.
Scott
See, that's the kind of stuff I like to hear. I'll give it a shot. Kind of like the old BFG R1 days. Just keep lowering the presure untill the *inside* of the tire cords.
Scott
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08-26-2003, 06:53 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
lol. Don't worry you won't cord the Azenis at 25psi....been there done that and they still work fine. I've actually been lower than 25 at a couple events to get my pig (ITR) to turn 
08-26-2003, 07:27 AM
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Re: How much pressure to make a Falken lose grip? (typer_801)
Man, I want to try lowering my rear tires now, but it just defies logic. Can anyone explain why it would make your car rotate more to lower the pressure in the rears with Azenis?
08-26-2003, 07:37 AM
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Re: How much pressure to make a Falken lose grip? (hatch2k)
I'm sure you could get the tire to lose grip at either extreme. Either you over inflate so the contact patch is the size of a quarter, or you underinflate to a point where the sidewall is the only thing holding the car up.
It seems to me there would be a better way... Maybe a different tire in back?
It seems to me there would be a better way... Maybe a different tire in back?
08-26-2003, 07:40 AM
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Re: How much pressure to make a Falken lose grip? (Floyd)
Floyd,
when I was at the FATT, I ran my first couple of sessions with the tires over inflated (duh, didn't think to check them, and with the heat, well, pressure rises with temp - some pesky pv = nrt kind crap).
With the tires around 36-38 pounds (cold) all around, the car was getting pretty squirly under braking - as in, the rear end was really wanting to step out braking for 1 at summit.
Setting the pressures back to the low 30s (31-33) made the world all better again.
just FYI.
when I was at the FATT, I ran my first couple of sessions with the tires over inflated (duh, didn't think to check them, and with the heat, well, pressure rises with temp - some pesky pv = nrt kind crap).
With the tires around 36-38 pounds (cold) all around, the car was getting pretty squirly under braking - as in, the rear end was really wanting to step out braking for 1 at summit.
Setting the pressures back to the low 30s (31-33) made the world all better again.
just FYI.
08-27-2003, 05:23 AM
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Re: How much pressure to make a Falken lose grip? (Angry Joe)
Update...
Well, it's easier to add air then take it out so I started off high. At 60 psi I had a bit better balance, with easy lift throttle oversteer, so looks like there is a high enough pressure. After 4 runs I tweaked the rear shocks, setting them softer (remember Celicas have funky rear-steer toe changes, so softer means more rear steer). With the softer shocks, the tires were much happier (before it was kind of on off oversteer), and I was able to slide the car nicely, and transitions felt very good.
I know Tom Hoppe was able to finally loosen his car up too. "I want to be able to run that sweeper wide open, and have the tail hang out all the way around..."
Yes, you *can* drift AWD, I witnessed it. He did just that, ran the sweeper wide open, with the rear trying to pass teh front the whole way around. It owuld have worked if it weren't for the next turn (where the rear did catch up to the front).
Scott
Well, it's easier to add air then take it out so I started off high. At 60 psi I had a bit better balance, with easy lift throttle oversteer, so looks like there is a high enough pressure. After 4 runs I tweaked the rear shocks, setting them softer (remember Celicas have funky rear-steer toe changes, so softer means more rear steer). With the softer shocks, the tires were much happier (before it was kind of on off oversteer), and I was able to slide the car nicely, and transitions felt very good.
I know Tom Hoppe was able to finally loosen his car up too. "I want to be able to run that sweeper wide open, and have the tail hang out all the way around..."
Yes, you *can* drift AWD, I witnessed it. He did just that, ran the sweeper wide open, with the rear trying to pass teh front the whole way around. It owuld have worked if it weren't for the next turn (where the rear did catch up to the front).
Scott
08-27-2003, 05:40 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by celica73 »</TD></TR><TR><TD CLASS="quote">
Yes, you *can* drift AWD, I witnessed it. He did just that, ran the sweeper wide open, with the rear trying to pass teh front the whole way around. It owuld have worked if it weren't for the next turn (where the rear did catch up to the front).</TD></TR></TABLE>
Hahahaha. Yeah, you need to be ready to catch it. Drifting on asphalt's never been an issue in the wagon. It's reeling it back in under power that's the issue. If you lift, even a little bit, you'll either powerslide sideways for a few seconds (like when I had Daddio in the car a couple weekends ago... "Wow, that was about 4 seconds of sideways.. made a course worker run) or you'll be facing the way you came (maybe a few times consecutively).
Sure you can make it lose grip, but getting it back when you need to is the fun part.
I'd rather have just a little bit and get it back earlier. Wait, what am I saying? Of course sideways is teh fast4r way around a course!
--kC
Yes, you *can* drift AWD, I witnessed it. He did just that, ran the sweeper wide open, with the rear trying to pass teh front the whole way around. It owuld have worked if it weren't for the next turn (where the rear did catch up to the front).</TD></TR></TABLE>
Hahahaha. Yeah, you need to be ready to catch it. Drifting on asphalt's never been an issue in the wagon. It's reeling it back in under power that's the issue. If you lift, even a little bit, you'll either powerslide sideways for a few seconds (like when I had Daddio in the car a couple weekends ago... "Wow, that was about 4 seconds of sideways.. made a course worker run) or you'll be facing the way you came (maybe a few times consecutively).
Sure you can make it lose grip, but getting it back when you need to is the fun part.
I'd rather have just a little bit and get it back earlier. Wait, what am I saying? Of course sideways is teh fast4r way around a course!
--kC
08-27-2003, 08:43 AM
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Re: How much pressure to make a Falken lose grip? (Todd00)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Falkens behave opposite of hoosiers. You need to lower pressure in the rear to get rotation.
Everyone tries some ungodly high pressures in the rear with those tires and that just doesn't work. Set the falkens down to around 25-28psi and have fun rotating.
</TD></TR></TABLE>
do you guys think it has to do with the fact that the Azenis has very stiff sidewalls?
I always recommend going with higher pressure on the rear (relative to the front) to achieve better rotation. At mid-ohio last year when I ran Sean L.'s ITR we experieced weird turn in oversteer but severe power understeer when we ran 38/30. You guys might find this report interesting:
http://www.g-speed.com/eg2/tq-...5.htm
they both autox a bit so i'm sure they ran the rear lower setup on azenis bc of what others autox ppl said. However I prove it to them that it didn't work at Mid-Ohio. Just FWIW and YMMV. I even made a fun pix:
Everyone tries some ungodly high pressures in the rear with those tires and that just doesn't work. Set the falkens down to around 25-28psi and have fun rotating.
</TD></TR></TABLE>
do you guys think it has to do with the fact that the Azenis has very stiff sidewalls?
I always recommend going with higher pressure on the rear (relative to the front) to achieve better rotation. At mid-ohio last year when I ran Sean L.'s ITR we experieced weird turn in oversteer but severe power understeer when we ran 38/30. You guys might find this report interesting:
http://www.g-speed.com/eg2/tq-...5.htm
they both autox a bit so i'm sure they ran the rear lower setup on azenis bc of what others autox ppl said. However I prove it to them that it didn't work at Mid-Ohio. Just FWIW and YMMV. I even made a fun pix:
08-27-2003, 08:44 AM
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Re: How much pressure to make a Falken lose grip? (celica73)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">Basic question, with a Falken, just how much pressure does it take to make it lose grip? I've run as high as 50 psi rear and 38 front, but I still can't get it to come around without excessive efforts (heavy trail braking, or big lifts), I want it to be subtle.
60 psi, 70 psi? There has to be a point where I've got dangerous levels of air in the tire...</TD></TR></TABLE>
why not try a less grippy tire on the back?
60 psi, 70 psi? There has to be a point where I've got dangerous levels of air in the tire...</TD></TR></TABLE>
why not try a less grippy tire on the back?
08-27-2003, 09:51 PM
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Re: How much pressure to make a Falken lose grip? (GhettoRacer)
Last weekend I had the privledge to run on an autox track built on a half mile oval.
I dropped my rear pressure to 26 and it worked great at high speed slaloms and the tighter inner part of the course.
I dropped my rear pressure to 26 and it worked great at high speed slaloms and the tighter inner part of the course.
08-27-2003, 11:18 PM
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Re: How much pressure to make a Falken lose grip? (celica73)
I have lots of experience running different pressures in race tires and street tires. I've never quite understood why people prefer to run higher pressures to get the car to rotate because higher pressures make the limit from grip to slide much more abrupt... not what you want.
I ran 24 psi in a 2000 Celica and won a national with it before I sold it. And more recently I ran 25 psi in the rear of the sts civic that won nationals at topeka last year. With lower pressure, you are still reducing grip, but you are allowing better limit characteristics (in my opinion) because you get more lateral movement out of the tire sooner than if it's 60 psi. That helps turn-in in a way 60 psi doesn't.
It's also a well known fact that more compliance in the tires generally makes the tire work better in the real world (read the late Carroll Smith's Tune to Win). To paraphrase...."There is an ideal pressure for a tire given a certain situation, and any more or less pressure will reduce that maximum traction. But in the real world, the lower pressure offers a less peaky traction curve that is easier to drive, and that makes you faster." And he's not talking about novices either.
So, don't hesitate to run lower pressures. I much prefer the lowr pressures for the better drivability, and who wouldn't want that? That's my story, and I'm sticking to it.
Chris Shenefield
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Now moving to a larger facility!
I ran 24 psi in a 2000 Celica and won a national with it before I sold it. And more recently I ran 25 psi in the rear of the sts civic that won nationals at topeka last year. With lower pressure, you are still reducing grip, but you are allowing better limit characteristics (in my opinion) because you get more lateral movement out of the tire sooner than if it's 60 psi. That helps turn-in in a way 60 psi doesn't.
It's also a well known fact that more compliance in the tires generally makes the tire work better in the real world (read the late Carroll Smith's Tune to Win). To paraphrase...."There is an ideal pressure for a tire given a certain situation, and any more or less pressure will reduce that maximum traction. But in the real world, the lower pressure offers a less peaky traction curve that is easier to drive, and that makes you faster." And he's not talking about novices either.
So, don't hesitate to run lower pressures. I much prefer the lowr pressures for the better drivability, and who wouldn't want that? That's my story, and I'm sticking to it.
Chris Shenefield
http://www.redshiftmotorsports.com
Now moving to a larger facility!
08-28-2003, 01:50 AM
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Re: How much pressure to make a Falken lose grip? (Todd00)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Todd00 »</TD></TR><TR><TD CLASS="quote">Falkens behave opposite of hoosiers. You need to lower pressure in the rear to get rotation.
</TD></TR></TABLE>
sorry about my ignorance, but i don't understand the logic in that..
woudn't lowering tire pressure increase the area of contact?
</TD></TR></TABLE>
sorry about my ignorance, but i don't understand the logic in that..
woudn't lowering tire pressure increase the area of contact?
08-28-2003, 02:31 AM
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Re: How much pressure to make a Falken lose grip? (ChrisShen)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I have lots of experience running different pressures in race tires and street tires. I've never quite understood why people prefer to run higher pressures to get the car to rotate because higher pressures make the limit from grip to slide much more abrupt... not what you want.</TD></TR></TABLE>
my experience sounds the opposite of you though... i did not think it was possible to have sharp turn in over steer, then then push as soon as we got on power. however that was at midohio on a medium speed road course.
in both cases (celia car and civic), what was your pressure relative to the front; exactly what pressure were you running? were those cold or hot pressure? cold i assume? the pressure i mentioned in my url are hot...
my experience sounds the opposite of you though... i did not think it was possible to have sharp turn in over steer, then then push as soon as we got on power. however that was at midohio on a medium speed road course.
in both cases (celia car and civic), what was your pressure relative to the front; exactly what pressure were you running? were those cold or hot pressure? cold i assume? the pressure i mentioned in my url are hot...
08-28-2003, 02:36 AM
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Re: How much pressure to make a Falken lose grip? (Mr.Integra)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">sorry about my ignorance, but i don't understand the logic in that..
woudn't lowering tire pressure increase the area of contact?</TD></TR></TABLE>
pressure changes has a major effect on the shape of the contact patch. lower elongates it (which incidentally is better for drag launches), higher makes it wider...
woudn't lowering tire pressure increase the area of contact?</TD></TR></TABLE>
pressure changes has a major effect on the shape of the contact patch. lower elongates it (which incidentally is better for drag launches), higher makes it wider...
08-28-2003, 02:56 AM
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Re: How much pressure to make a Falken lose grip? (GhettoRacer)
In both cases (civic and celica), I ran normal front pressures (38-42 ish) to maximize grip and only ran the rears at the lower pressure. Also, this is an autocross car, and the pressures are the same cold or hot (I bleed them down from run to run). Anyway, perhaps there is some reason that a road race car should be setup differently.... and also there are some very good and experienced autocrossers that run higher pressures to get the car to rotate; so it can't be all bad. I just think it's not the preferred way to go.
I think whatever is fast is right. And fast for a fwd car in autocross is relatively high levels or lateral rear movement, and if you have good control of that lateral movement and can enter turns hard without loosing the rear of the car while exiting without pushing, then you definitely have a fast autox car. And the fastest car will be the one that can be pushed the most, all else equal; so that's my reasoning for running the lower pressures.
Oh, and one other thing that's important is that the tire pressures dictate how much traction you have; and the proper way to setup the balance of the car is (in this order) springs, swaybars, shocks, tire pressures. So, if you have to do major tire pressure changes from optimum, then something about the setup is wrong. With my Celica, it was that the car was a E-Stock car and there wasn't much tuning options....and those 2000 celicas don't like much changing toe in the rear because of their rear geometry. With the Civic, I did it because I didn't have time to try different option before nationals; so I got close on the hardware setup, then I used tire pressures in rear to get the car to rotate like I needed it to. That's all.
And finally, I'm going by the theory that a tires air pressure for maximum lateral grip is dependent on the weight it carries. So, a tire that has more weight on it needs more air in it to get the most lateral grip out of it. And that's why the rear of a fwd car has pressures below the front to start out with... because there is less weight there. and then going down from there means it's going way down.
So someone running equal pressures front and rear on a car with a 60/40 weight balance is not actually running the theoretical maximum grip on there car. Although it might be "balanced" for a particular course very well like that.
Chris
I think whatever is fast is right. And fast for a fwd car in autocross is relatively high levels or lateral rear movement, and if you have good control of that lateral movement and can enter turns hard without loosing the rear of the car while exiting without pushing, then you definitely have a fast autox car. And the fastest car will be the one that can be pushed the most, all else equal; so that's my reasoning for running the lower pressures.
Oh, and one other thing that's important is that the tire pressures dictate how much traction you have; and the proper way to setup the balance of the car is (in this order) springs, swaybars, shocks, tire pressures. So, if you have to do major tire pressure changes from optimum, then something about the setup is wrong. With my Celica, it was that the car was a E-Stock car and there wasn't much tuning options....and those 2000 celicas don't like much changing toe in the rear because of their rear geometry. With the Civic, I did it because I didn't have time to try different option before nationals; so I got close on the hardware setup, then I used tire pressures in rear to get the car to rotate like I needed it to. That's all.
And finally, I'm going by the theory that a tires air pressure for maximum lateral grip is dependent on the weight it carries. So, a tire that has more weight on it needs more air in it to get the most lateral grip out of it. And that's why the rear of a fwd car has pressures below the front to start out with... because there is less weight there. and then going down from there means it's going way down.
So someone running equal pressures front and rear on a car with a 60/40 weight balance is not actually running the theoretical maximum grip on there car. Although it might be "balanced" for a particular course very well like that.
Chris
08-28-2003, 03:02 AM
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Re: How much pressure to make a Falken lose grip? (ChrisShen)
good back ground on your setup. thanks for sharing.but let me ask you this, in both cars, did you try higher pressure on the back to see how it would feel?
we can probably agree that we maximize front end, and than tune the rear according to get the rotation we want (which, going extra hi or extra low relative to the front pressure are both valid ways). trying to picture what happens to the tires to cause turn in oversteer than power understeer in the ITR's @ mid-ohio was difficult... but the pressure change (going 38/00 hot to about 40/42 hot the next day) made a dramatic difference on the handling behavior. the car felt better turning all phase of cornering (turn in, mid corner, and exit). in autox it is more busy and everything happenes faster... and like you said i know good drivers and some go higher tire pressure on back, some go lower. but if we consider tire pressure as part of the spring rate, then wouldn't that support the higher rear tire pressure?
one reason i don't like lower pressure on back is that softens the sidewall support a bit (from the pressure) allows the tires to roll over a bit. it makes the rear end feel more vague. my theory on the ITR @ midohio is that with lower pressure, during turn in the lower pressure reduce the contact match and make it narrower and longer, reducing rear grip. the tire flex from turn in breaks the rear end lose. however, as soon as power is applied, it plants the rear, rear tire flex is nomore because now car is at steady state cornering, and also the weight transfer from getting on power gives the rear too much grip, thus now we get power understeer.
i have to say turn in oversteer but quickly into power understeer was the most odd handling behavior i have experienced. I remember a while back one of the road racers here was complainng his car did that. I thought he didn't know what he was talking about heheh. Then I experienced it with the ITR @ Mid-Ohio. I wonder if that guy ever figured out the cause of his problem?!
Modified by GhettoRacer at 6:05 AM 8/28/2003
08-28-2003, 05:02 AM
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Re: How much pressure to make a Falken lose grip? (GhettoRacer)
Very helpful discussion. Having tried it both ways myself, I have to agree with Todd and Chris that lower pressures work better for the Azenis. From 45 to over 50 psi in the rear on my car, it still did not provide that same kind of predictable and comfortable rotation as did the lower pressures. I have yet to try 30 psi or below in my car, so I think I'll do that next time.
Casey, who says it ain't so easy getting my DB8 beast STS of a car to rotate....
Casey, who says it ain't so easy getting my DB8 beast STS of a car to rotate....
08-28-2003, 05:18 AM
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Re: How much pressure to make a Falken lose grip? (ChrisShen)
Chris-
Thanks for the insights! I agree, with the high pressure, the transition from grip to slip was quite abrupt. I compensated a bit for this by going with softer shocks in the rear, and it did feel better. I will have to try low pressure at the next event.
One side note, with the 2000 Celica, the rear camber curve is very good, I was wicked loose on turn-in with just -1.7 degrees in the rear, and I HAD to use 20 psi or less to just keep the rear where it belonged (I attribute this to the poor static contact patch shape when the rear had no cornering loads - if I didn't spin on turn in, the car felt great in the turns). When I set the camber to -1.3 degrees it was no longer spinning on turn in, no other changes, suddenly I could run "normal" rear tire pressures. I've only developed the push since I cheaped out this season and started running Falkens instead of Hoosiers.
Good thread guys, thanks for all the input!
Scott
Thanks for the insights! I agree, with the high pressure, the transition from grip to slip was quite abrupt. I compensated a bit for this by going with softer shocks in the rear, and it did feel better. I will have to try low pressure at the next event.
One side note, with the 2000 Celica, the rear camber curve is very good, I was wicked loose on turn-in with just -1.7 degrees in the rear, and I HAD to use 20 psi or less to just keep the rear where it belonged (I attribute this to the poor static contact patch shape when the rear had no cornering loads - if I didn't spin on turn in, the car felt great in the turns). When I set the camber to -1.3 degrees it was no longer spinning on turn in, no other changes, suddenly I could run "normal" rear tire pressures. I've only developed the push since I cheaped out this season and started running Falkens instead of Hoosiers.
Good thread guys, thanks for all the input!
Scott