First time AutoX UMI AFCO Coilovers Video - LS1TECH



Road Racing Road Course | Autocross

First time AutoX UMI AFCO Coilovers Video

Reply
 
Thread Tools Search this Thread
Old 10-25-2016, 12:43 PM   #1
TECH Enthusiast
Thread Starter
iTrader: (13)
 
Cpt.Derrek's Avatar
 
Join Date: Oct 2010
Location: Ventura, CA
Posts: 527
Default First time AutoX UMI AFCO Coilovers Video

First time AutoX with my new UMI AFCO Coilovers and UMI RR K-member and A Arms. They performed great! and I meant to try to adjust the rebound settings but was too lazy to get up under there to try and mess around with that. I had them right about in the middle setting. First time for a lot of things on my car so it was more of a learning experience then really competitive but I set my goal at the start of the day to get a 38 second run and on my very last run I was able to get it so I left feeling very accomplished, only ended up in 13th place overall though... still beat a dodge Viper ACR

Anyways enjoy the video

Car setup
Stock LS1 with bolt-ons
4l80e w/3k triple disc 10.5" CircleD converter
UMI AFCO coilovers
UMI RR K-Member
UMI Boxed A-Arms
-1.5 chamber 3.5 caster 0 toe
UMI full length torque arm
MWC Watts link
LCA relocation bracket
Strano hollow sway bars
CTS-V brembo Front brakes
285 front 305 rear Continental Extreme Contact DR tires

Last edited by Cpt.Derrek; 10-25-2016 at 12:48 PM.
Cpt.Derrek is offline   Reply With Quote
Old 10-25-2016, 03:54 PM   #2
TECH Resident
 
Join Date: Oct 2006
Posts: 779
Default

Those tires need a lot more camber to work properly - closer to 3 degrees would be ideal. Also, additional caster would be desirable. You should have plenty of adjustment with those UMI parts. Run as much as you can get, I run over 7 degrees in my car.
79_T/A is offline   Reply With Quote
Old 10-25-2016, 04:54 PM   #3
TECH Enthusiast
Thread Starter
iTrader: (13)
 
Cpt.Derrek's Avatar
 
Join Date: Oct 2010
Location: Ventura, CA
Posts: 527
Default

Quote:
Originally Posted by 79_T/A View Post
Those tires need a lot more camber to work properly - closer to 3 degrees would be ideal. Also, additional caster would be desirable. You should have plenty of adjustment with those UMI parts. Run as much as you can get, I run over 7 degrees in my car.
Thanks for the tips. The alignment shop only gave me 3.5 even though I requested 4.5 and they charged me a boat load of money to do this, unless I can find a better performance alignment shop I don't want to touch the alignment again. I also won't replacing these tires with the same type, I just ran these because I got them used for a great price. I'll probably replace them with some semi slicks 295 wide.
Cpt.Derrek is offline   Reply With Quote
Old 10-25-2016, 06:25 PM   #4
TECH Enthusiast
 
30thanniv's Avatar
 
Join Date: Aug 2004
Location: Florida
Posts: 730
Default

Excellent. Love it!!
30thanniv is offline   Reply With Quote
Old 10-26-2016, 07:58 AM   #5
On The Tree
iTrader: (1)
 
gscherer78ta's Avatar
 
Join Date: Nov 2013
Location: Fort Worth, TX
Posts: 152
Default

The car looks great out there!
gscherer78ta is offline   Reply With Quote
Old 10-26-2016, 11:17 AM   #6
TECH Fanatic
iTrader: (6)
 
CamaroSS27's Avatar
 
Join Date: Jan 2009
Location: Denton, TX
Posts: 1,476
Default

great job man, can't wait to get those coilovers for my ride.
CamaroSS27 is offline   Reply With Quote
Old 10-26-2016, 11:32 AM   #7
Launching!
iTrader: (2)
 
Join Date: Jan 2004
Location: State College, PA
Posts: 281
Default

And that's a good looking TA too.
Chris Paveglio is offline   Reply With Quote
Old 10-27-2016, 10:03 AM   #8
TECH Fanatic
 
Join Date: Feb 2012
Posts: 1,402
Default

Is it me or does the car seem to roll/dip quickly then find it's steady state compression around turns? May be your inputs as well.

You have a lot of adjustable parts. I agree, more camber is needed. I'm about -2.5 maxed castor and 1/8" toe out. Lots of fine tuning in your future.

Where do you have your watts link set?
smitty2919 is offline   Reply With Quote
Old 10-27-2016, 10:49 AM   #9
TECH Enthusiast
Thread Starter
iTrader: (13)
 
Cpt.Derrek's Avatar
 
Join Date: Oct 2010
Location: Ventura, CA
Posts: 527
Default

Quote:
Originally Posted by smitty2919 View Post
Is it me or does the car seem to roll/dip quickly then find it's steady state compression around turns? May be your inputs as well.

You have a lot of adjustable parts. I agree, more camber is needed. I'm about -2.5 maxed castor and 1/8" toe out. Lots of fine tuning in your future.

Where do you have your watts link set?
Thanks for pointing that out. I feel like it rolls/dips more than I would have liked but I have nothing to compare it to. I had one of the drivers there ride with me and he said the same thing but only thing that I can think of is to get stiffer springs.

As far as the alignment I still want to car to be street friendly not all out racecar but I would like to get some on-car adjustable upper a-arms so I can adjust when I'm at the track, and with that I'd be able to get my desired spec.

I have my Watts link set to lowest hole while keeping the arms parallel to keep my roll center as low as possible, if you think that needs to be adjusted let me know.
Cpt.Derrek is offline   Reply With Quote
Old 10-27-2016, 11:24 AM   #10
TECH Fanatic
 
Join Date: Feb 2012
Posts: 1,402
Default

The lower you go with the watts link the more spring rate you need to compensate...what are your rear spring rates? I have mine set to 2nd hole from the top and running 150rate Strano spring. Also you only need to keep the "arms" parallel during initial installation when you start at the middle hole. You can then move the propeller up/down and not worry if the arms are parallel to the ground.

Moving the watts link up = oversteer tendencies
Moving it down = understeer tendencies

This is assuming NOTHING else changes. We all know bar rates and tires play a roll in oversteer/understeer.

Also, are your shocks compression adjustable? If so you can "increase" the dampening of the shocks upon compression. In other words you make the shock harder to compress. This may slow down the initial fast roll you see.

Having the shocks rebound adjustable allows you to slow down that rate at which the spring will pull them out.
smitty2919 is offline   Reply With Quote
Old 10-27-2016, 01:38 PM   #11
TECH Enthusiast
Thread Starter
iTrader: (13)
 
Cpt.Derrek's Avatar
 
Join Date: Oct 2010
Location: Ventura, CA
Posts: 527
Default

Quote:
Originally Posted by smitty2919 View Post
The lower you go with the watts link the more spring rate you need to compensate...what are your rear spring rates? I have mine set to 2nd hole from the top and running 150rate Strano spring. Also you only need to keep the "arms" parallel during initial installation when you start at the middle hole. You can then move the propeller up/down and not worry if the arms are parallel to the ground.

Moving the watts link up = oversteer tendencies
Moving it down = understeer tendencies

This is assuming NOTHING else changes. We all know bar rates and tires play a roll in oversteer/understeer.

Also, are your shocks compression adjustable? If so you can "increase" the dampening of the shocks upon compression. In other words you make the shock harder to compress. This may slow down the initial fast roll you see.

Having the shocks rebound adjustable allows you to slow down that rate at which the spring will pull them out.
Ok cool Thank you very much for the information, I didn't find much when searched online for it, I found that having the propeller mounted higher you get more roll steer and lower is less roll steer but that's all I found.

I am running the UMI provided 600# front and 200# springs rates, but I think I have mine the 3rd from the top, I can't go up any higher. Maybe try lower? Though my rear end felt pretty planted and I couldn't even get much rotation if any coming out of turns.

The shocks are fixed medium firm compression but adjustable rebound set to the about the middle setting, maybe try softening rebound?
Cpt.Derrek is offline   Reply With Quote
Old 10-27-2016, 02:56 PM   #12
TECH Fanatic
 
Join Date: Feb 2012
Posts: 1,402
Default

Wait you said on post #9 that your WL is set to the lowest hole...then in post #11 you say it is 3rd from the top??

Overall the lower you move the propeller down, the more spring rate you need (your 200# should be fine and allow you to) and the more understeer.

"stiffening" rebound shock adjustment slows down the shocks ability to extend.
"softening" rebound shock adjustment allows the shock to extend quicker.

I have found there is no exact science to suspension tuning. There are obvious DO's and DON'Ts but it boils down to gaining seat time and growing with the car so you two mesh well together to shave seconds.

I have strano springs and koni rebound adj shocks...DON"T adjust rear shocks to full stiff or it will be as if your rear end is on ice....ask me how I know

It's all controlling the weight transfer rate and matching it to your driving style. If the rear is allowed to transfer the weight faster and therefore reach the grip limit of the tire faster than the front...oversteer. That comes from stiff rear shocks,stiff bars, stiff springs and more air in the rear tire.

You could get in my car and hate it. But it works well for me. Trial and error and have fun!

IMO, since you just got new C/O's, set everything to "neutral" or middle ground. Drive the car and tweak one thing at a time. Figure out what you want the car to do that it's not doing, and adjust accordingly.
smitty2919 is offline   Reply With Quote
Old 10-27-2016, 03:45 PM   #13
TECH Enthusiast
Thread Starter
iTrader: (13)
 
Cpt.Derrek's Avatar
 
Join Date: Oct 2010
Location: Ventura, CA
Posts: 527
Default

Quote:
Originally Posted by smitty2919 View Post
Wait you said on post #9 that your WL is set to the lowest hole...then in post #11 you say it is 3rd from the top??

Overall the lower you move the propeller down, the more spring rate you need (your 200# should be fine and allow you to) and the more understeer.

"stiffening" rebound shock adjustment slows down the shocks ability to extend.
"softening" rebound shock adjustment allows the shock to extend quicker.

I have found there is no exact science to suspension tuning. There are obvious DO's and DON'Ts but it boils down to gaining seat time and growing with the car so you two mesh well together to shave seconds.

I have strano springs and koni rebound adj shocks...DON"T adjust rear shocks to full stiff or it will be as if your rear end is on ice....ask me how I know

It's all controlling the weight transfer rate and matching it to your driving style. If the rear is allowed to transfer the weight faster and therefore reach the grip limit of the tire faster than the front...oversteer. That comes from stiff rear shocks,stiff bars, stiff springs and more air in the rear tire.

You could get in my car and hate it. But it works well for me. Trial and error and have fun!

IMO, since you just got new C/O's, set everything to "neutral" or middle ground. Drive the car and tweak one thing at a time. Figure out what you want the car to do that it's not doing, and adjust accordingly.
haha my bad, I set the hole to the lowest point I could while keeping the bars parallel, which was the 3rd hole down from the top. So should I try to lower my the hole some more?

The driver that rode with me said about the same thing you're saying about the setup and driving style. When I asked him if there was anything he'd adjust he just said he'd personally like it stiffer but with the current setup it works with my driving style.

Right now I do have the shocks in the middle setting but I also don't know what to expect or how the change will feel on the track, but I guess that's what getting seat time and test and tuning is for. I have a track event the 3rd of December with unlimited access to the track so I guess that'll be the perfect time for test and tuning

Thanks again for the help Smitty2919 its definitely helpful having a another set of eyes.
Cpt.Derrek is offline   Reply With Quote
Old 10-27-2016, 04:32 PM   #14
TECH Fanatic
 
Join Date: Feb 2012
Posts: 1,402
Default

Only worry about the bars being parallel when using the middle hole. You install the watts link using the middle hole. Once that is set, you can move up and down all you want.

Seat time and messing with stuff is name of the game. Drive it with everything neutral and adjust from there. Only one way to find out is to tinker and learn by doing
smitty2919 is offline   Reply With Quote
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
What cool new stuff has UMI been up to? See inside! UMI Performance Suspension & Brakes 214 04-27-2017 08:05 AM
HOSS LS7/T56 Build Thread WVhuggerSS Generation IV Internal Engine 85 08-29-2016 04:00 PM
It's finally time blackandgold Suspension & Brakes 16 06-06-2016 04:50 PM
Tubular K-member & control arm advice floman Drag Racing Tech 6 04-25-2016 12:11 PM
coilovers or just a good shock/spring combo? fastassls1maro Suspension & Brakes 3 07-31-2013 08:24 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 03:42 PM.


 
  • Ask a Question
    Get answers from community experts
What's your question?
Send