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 Post subject: Re: Mid-corner oversteer
PostPosted: August 31, 2017, 2:32 am 
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Joined: January 10, 2008, 4:47 pm
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Location: Massachusetts
I think a camera would work well. I didn't have much luck trying to use something like a tie wrap on the coilover shaft. The thing is you have bumps and very quickly they just push the tie wrap all the way up. That was on my formula ford and it was sprung stiffer than most.

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 Post subject: Re: Mid-corner oversteer
PostPosted: August 31, 2017, 4:50 pm 
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Joined: July 4, 2006, 5:40 pm
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Location: Novato, CA
Seems to me you need more front spring and more rear shocks. If it were me, that's where I'd start. Assuming the travel thing isn't an issue, which it doesn't sound like.


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 Post subject: Re: Mid-corner oversteer
PostPosted: August 31, 2017, 10:28 pm 
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Joined: June 8, 2010, 8:02 pm
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Location: White Rock, BC, Canada
Lots of good input. Thanks guys.
I was at the shop last night but only was able to have a quick look at the suspension. For bind, I am sure I checked through the entire range that there was no suspension bind. As far as shock travel, I can see little oil lines of where the shock has travelled recently. The LR shows still 3/8" travel until bumpstop and shows no signs of bumpstop contact. The RR bumpstop has been used (probably with heavy passenger). Bumpstops are fairly large, well shaped units inside the coilovers. I can't see the springs binding, but didn't measure. I have a little camera I should be able to use to watch the shocks. Lower arms are level and probably 15"(? eyeballed only). I think I may have lied about my antisquat. I am not in my max setting, so probably have a more reasonable amount of it.

I will do some testing/filming and update as I know more. I may put some slower tires on so I can check the feel of it at lower speeds too. With the R-comps, it has a little too much kinetic energy to be trying out anywhere other than at autoX etc.

Cheers.

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 Post subject: Re: Mid-corner oversteer
PostPosted: September 1, 2017, 10:45 pm 
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Joined: February 8, 2014, 10:47 pm
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Location: Cornholio OR "Where the magic happens"
Check up travel?

Put a GoPro on it to see what is happening?

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 Post subject: Re: Mid-corner oversteer
PostPosted: September 4, 2017, 1:45 am 
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Joined: August 27, 2005, 1:04 am
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Location: Kamloops, BC, Canada
C10CoryM wrote:
Coming from the same gutless FWD background, I considered that as well and definitely think it may be a factor. The S/C tends to slap the throttle-plate closed very fast so mine could even be worse. Did you notice it while trying to finesse the throttle around a sweeper as well? As in, noticing understeer so touch throttle to sort it out then reduce throttle and surprise oversteer? I have been dealing with a sticky throttle (off idle) which was a real struggle to drive yesterday. That is high priority to get sorted (and make sure my S/C valves are working). My driving skills are not up to this car yet, but my experienced friend didn't think it was from engine braking. Though I'm not sure he's driven a car with this engine/weight ratio before. I'll ask.

Thanks again for the input so far. It helps.


Honestly? I was such a hack and in so far over my head that when I first started autocrossing it I had to resort to pushing the clutch in around every corner so that I didn't spin it. On my first ever run with it I spun the car three times. Once I learned how the car handles and got my brain up to speed with the car (almost), I was able to pretty much balance the cornering attitude of the car with the throttle, from understeer to basically as much oversteer as I want, and it's a ton of fun doing it now. I did end up going to stiffer springs due to the amount of body roll I was getting though, but by that time I was getting a handle on the car and getting a lot better at driving it already. Try pushing the clutch when you go into a corner, that should eliminate any concerns about it being engine braking.
Kristian

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 Post subject: Re: Mid-corner oversteer
PostPosted: August 8, 2018, 10:42 pm 
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Update: First event of the year and the morning was massive oversteer everywhere. I set my front shocks full stiff, and full soft in rear and it was much more sorted. I'm going to have to run out the season as is, but this winter a front swaybar will be high priority.


Thanks again!

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 Post subject: Re: Mid-corner oversteer
PostPosted: August 9, 2018, 9:24 am 
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Joined: July 3, 2015, 7:15 pm
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Location: Atlanta GA Area
Sounds like it could be a few things. Worn out or too much air pressure in rear tires. Too small a width in rear tires for power being applied. Possible roll steer in your rear suspension as in unloads the inside tire and then loses traction.
You Should get photos of the amount of lean you have in a corner to determine roll angle and solve for that if too much. I have a nice big bar on the back of mine now. :)
Good luck.

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 Post subject: Re: Mid-corner oversteer
PostPosted: August 9, 2018, 9:49 pm 
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Rudy14 wrote:
Sounds like it could be a few things. Worn out or too much air pressure in rear tires. Too small a width in rear tires for power being applied. Possible roll steer in your rear suspension as in unloads the inside tire and then loses traction.
You Should get photos of the amount of lean you have in a corner to determine roll angle and solve for that if too much. I have a nice big bar on the back of mine now. :)
Good luck.


I think once I stiffen up the front with a swaybar and transfer the weight to the inside corner I may be in good shape. Rear tire pressure is as low as possible, but so are the fronts (20psi min). Tire wear is pretty even but need more seat time to tell. Current tires are ancient, but still have decent grip until they overheat. Have new ones sitting here but they won't fit w/o redoing fender stays so will have to wait until winter. I'll check for roll-steer next time I am on the alignment machine, but I think I'm good there. I was careful about that in design.

Thanks.

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