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Horrible understeer

Bluemustang

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an alignment doesn't fix the squirrely IRS. But if your level of investment is going to be the absolute leastest, then sure an alignment can help.

I'm interested in FIXING engineering mistakes.

An IRS that can move and deflect all around is an ERROR.
A diff that can bounce all over the place and has the WRONG freaking bolts in the rear is an ERROR.
A set of shocks that are underdamped in rebound is an ERROR, not a "preference".
Exactly. There is so much I could go into - but just to point out one thing. The IRS in stock form is HORRIBLE. Anyone who has seen a video showing the deflection would have to be scared shitless driving the car hard with it like that.
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TeeLew

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I have ride-height adjustable coil-overs. :)
But point taken. I probably should have said "stock'ish RATE rear springs"
Gotcha. I think that's all that's necessary, at least for a 200tw tire. Ya, you can run higher rates, but I just don't see any advantage to it.
 

1958cyclist

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OK, now that I have 99% of my suspension mods done, Steeda stop the hop, knuckle bearings, 200/800 springs, good struts and shocks, all the normal upgrades. It plows like a Mack truck, even with 295/35 19 R7's square

I read a lot where people recommend larger front sway bars?? Wouldn't this make it understeer more????

So what should I do to balance the car out. HPDE type events, no competition other than me against me per lap.

Thanks
Yes, camber plates properly adjusted will certainly help keep as much flat tire on road surface as possible. I have a similar setup to yours: Steeda Sport Springs, with 295-30-19 front and 305-30-19 rear. Everything else is stock PP1. The course I frequent is very tight and technical so I've found that -2.9 camber seems to work pretty well for the occasional track day. I leave it set at this setting for street as well. It's not a daily driver, so I'm overly concerned about tire wear.
 

bnightstar

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The course I frequent is very tight and technical so I've found that -2.9 camber seems to work pretty well for the occasional track day. I leave it set at this setting for street as well. It's not a daily driver, so I'm overly concerned about tire wear.
Can I ask about that my camber is -3.2 at the moment (minimum possible to tug the 305/30) inside however when on PP1 wheels on full lock they scrub on the inside with the 255/40/19 tires and this is annoying the shit out of me because I need full lock to get into my garage ... Anyone else having similar problem ?
 

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Flyhalf

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Pressure is 43 hot

Yes more spring is needed.
Well. I think you find the issue :)
43 hot is .
Just too much.
34 is optimal. Lower even better.

Yeah i know. Hoosier suggests that. It is just the joke of the race community tho. At 46hot simply...there is no grip .
They do.that to protect themselves.
I run 30 hot. But for time trials. So 34 -36 hot for longer stints is perfect.

Reduce the pressure to 34 hot. And pls report the result.

Feel free to share your video too.
That is where i can be helpful in case you have some other issues 🙂
 
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K4fxd

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bnightstar

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Long studs and wheel spacers are the answer.
I don't want to run spacers because it's dangerous seen it time and again at my local track people loosing wheels no thank you.
 

TeeLew

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I don't want to run spacers because it's dangerous seen it time and again at my local track people loosing wheels no thank you.
There are 2 types. Through bolt spacers with extended studs are every bit as robust as a wheel with a longer hub. There's no physical difference.

If a 5-lug nut came loose, then it likely wasn't tightened correctly. If they tightened the wheel on with the spacer not seated, that could cause the problem you mention. This is not a problem with the parts. It's a problem with the mechanic.
 

luc

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I don't want to run spacers because it's dangerous seen it time and again at my local track people loosing wheels no thank you.
That is nonsense
The correct type of spacers do not add any more load than a wheel with the same effective offset
 

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bnightstar

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There are 2 types. Through bolt spacers with extended studs are every bit as robust as a wheel with a longer hub. There's no physical difference.

If a 5-lug nut came loose, then it likely wasn't tightened correctly. If they tightened the wheel on with the spacer not seated, that could cause the problem you mention. This is not a problem with the parts. It's a problem with the mechanic.
I don't want to argue on the topic of wheel hubs I just don't want to use them I have ET26 19x11 SM-10 and they work perfect with the 305/30 with -3.20 camber. My problem is with the OEM PP1 wheels and my oem 255/40 tires when I have -3.20 camber the top of the tire is touching inside on a full lock. Which is very annoying when parking in the garage. No rubbing on the street (when not parking) or on the track with the track set.
 

luc

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I don't want to argue on the topic of wheel hubs I just don't want to use them I have ET26 19x11 SM-10 and they work perfect with the 305/30 with -3.20 camber. My problem is with the OEM PP1 wheels and my oem 255/40 tires when I have -3.20 camber the top of the tire is touching inside on a full lock. Which is very annoying when parking in the garage. No rubbing on the street (when not parking) or on the track with the track set.
Running-3.2 on the street is quite extreme and obviously the factory pp1 front wheel has too much positive offset for the amount of camber
 

shogun32

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you can safely run 5mm worth of spacer on the stock lugs. Does that solve the problem sufficiently?
 

luc

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you can safely run 5mm worth of spacer on the stock lugs. Does that solve the problem sufficiently?
Correct but i was not going to suggest it due to the dislike for spacers
Used to run pp1 rear in the front with 5mm spacers
 

Dave2013M3

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Sorry, R7 wheels? What sizes and offsets. You said square setup, so wondering if you are talking about a 10" wide wheel vs. an 11" wide wheel. Sorry never heard of these unless you mean the R357 SVE wheels.
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