Welcome to the North American Subaru Impreza Owners Club Thursday April 9, 2020
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC General > Motorsports

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 03-22-2020, 10:34 PM   #101
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

I was about to say that. I too have wishbone.exe.
* Registered users of the site do not see these ads.
Homemade WRX is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 03-23-2020, 12:36 AM   #102
JDwhiteWRX
Scooby Specialist
 
Member#: 190502
Join Date: Sep 2008
Chapter/Region: International
Location: Sydney, Australia
Default

Quote:
Originally Posted by Homemade WRX View Post
I was about to say that. I too have wishbone.exe.
I managed to get it working last night on W10 so all I need to do now is go re-measure everything. As of today I am "working from home" indefinitely so I should have plenty of time.
JDwhiteWRX is offline   Reply With Quote
Old 03-23-2020, 08:11 PM   #103
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

Yeah, I think we're all finding a bit more time in the garage now
Homemade WRX is offline   Reply With Quote
Old 03-24-2020, 08:27 AM   #104
Hardrvin
Scooby Newbie
 
Member#: 63647
Join Date: Jun 2004
Chapter/Region: MWSOC
Location: Evansville, IN
Vehicle:
05 FXT
12.5 @ 109

Default

Quote:
Originally Posted by JDwhiteWRX View Post
I managed to get it working last night on W10 so all I need to do now is go re-measure everything. As of today I am "working from home" indefinitely so I should have plenty of time.
Always keen to hear how the rest of the world is managing.

I’ve popped in and out of this thread so sorry if it’s been covered. Did you look at the dive geometry as well or make it adjustable?

Last edited by Hardrvin; 03-27-2020 at 01:38 AM.
Hardrvin is offline   Reply With Quote
Old 03-24-2020, 06:44 PM   #105
JDwhiteWRX
Scooby Specialist
 
Member#: 190502
Join Date: Sep 2008
Chapter/Region: International
Location: Sydney, Australia
Default

Quote:
Originally Posted by Hardrvin View Post
Always keen to here how the rest of the world is managing.

Iíve popped in and out of this thread so sorry if itís been covered. Did you look at the dive geometry as well or make it adjustable?
I have left anti-dive out of the front suspension, there is still some angle there but its just enough to allow for rake so it doesn't go into pro-dive. I can also adjust a very small amount of angle into the control arms by playing with the spacers where the arms attach to the chassis.

This was something I considered for a long time, it seems like some professional builds remove it and some leave it in. I've had a good look at many cars at WTAC over the years, Under Suzuki's new build had no anti-dive but the HKS TRB03 had left it in for example.
JDwhiteWRX is offline   Reply With Quote
Old 03-26-2020, 05:49 PM   #106
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

Quote:
Originally Posted by JDwhiteWRX View Post
I've had a good look at many cars at WTAC over the years, Under Suzuki's new build had no anti-dive but the HKS TRB03 had left it in for example.
Was Suzuki running a 3rd spring for downforce and the TRB03 wasn't?
Homemade WRX is offline   Reply With Quote
Old 03-26-2020, 07:53 PM   #107
JDwhiteWRX
Scooby Specialist
 
Member#: 190502
Join Date: Sep 2008
Chapter/Region: International
Location: Sydney, Australia
Default

Quote:
Originally Posted by Homemade WRX View Post
Was Suzuki running a 3rd spring for downforce and the TRB03 wasn't?
This is true but they were just a couple of examples off the top of my head. I went back and looked at some more of my photos and again its a mix of some have it and some don't, Under's car was the first to compete a 3rd spring as previously they were not allowed.

A quote from Carroll Smith's Tune to Win book:

How much anti-dive a given car can tolerate is a question
of the height and fore and aft location of the c.g., wheelbase
length, mass and the expected rate of retardation. Present
practice is to use none on Formula Cars and Sports racing
Cars-they don't need it and, due to their inherently sensitive
natures, they can't tolerate the upsets. Large front
engined Sedans, on the other hand, aren't very sensitive to
begin with and need all of the help they can get and typically
feature 20% to 25% anti dive.
JDwhiteWRX is offline   Reply With Quote
Old 03-26-2020, 11:45 PM   #108
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

A lot of current TA is far beyond what Carroll studying. The downforce numbers have become quite wild.

If not running a 3rd spring, the spring rates have to be crazy high. So no wonder the minor CG pitch forward wouldn't effect dynamics in such a combo.
Homemade WRX is offline   Reply With Quote
Old 03-27-2020, 06:04 AM   #109
JDwhiteWRX
Scooby Specialist
 
Member#: 190502
Join Date: Sep 2008
Chapter/Region: International
Location: Sydney, Australia
Default

Yes the Tilton Evo was running 1800kg front springs this year.
JDwhiteWRX is offline   Reply With Quote
Old 03-27-2020, 11:21 PM   #110
speedyHAM
Scooby Specialist
 
Member#: 48377
Join Date: Nov 2003
Chapter/Region: MWSOC
Location: "They eat fish soaked in lye"
Vehicle:
1996 Gutted, built
XP class Impreza L

Default

Quote:
Originally Posted by JDwhiteWRX View Post
Yes the Tilton Evo was running 1800kg front springs this year.
Wow- that's huge
speedyHAM is offline   Reply With Quote
Old 03-27-2020, 11:37 PM   #111
JDwhiteWRX
Scooby Specialist
 
Member#: 190502
Join Date: Sep 2008
Chapter/Region: International
Location: Sydney, Australia
Default

A few photos off my phone form WTAC last year.

Tilton Evo after the tire failure.


Front springs


Under's new car after he crashed in practice, you can see the upper control arm is level. I also have photos of the Nemo Evo and RP968 with level front control arms.
JDwhiteWRX is offline   Reply With Quote
Old 03-28-2020, 08:32 AM   #112
Norm Peterson
Scooby Specialist
 
Member#: 498642
Join Date: Mar 2019
Chapter/Region: Tri-State
Location: our wrx IS the family sedan
Vehicle:
'19 WRX Limited 6M
'08 Mustang GT (the toy)

Default

Quote:
Originally Posted by JDwhiteWRX View Post
Yes the Tilton Evo was running 1800kg front springs this year.
Something's doesn't feel quite right here. Even if that 1800 was in N/mm, that's still something like 10,300 lb/in, and the front sta-bar in the second picture would basically be just ballast.

I have a suspicion that the 190-65-1800 designation is in mixed units, metric for the dimensions and "English" for the rate. 1800 lb/in is still pretty darn firm, but it's a rate that's fairly easy to source.


On edit, 65mm OD x 18mm wire diameter x 190mm free length with 6 active coils ==>right around 1800 lb/in.


Norm

Last edited by Norm Peterson; 03-28-2020 at 08:40 AM.
Norm Peterson is offline   Reply With Quote
Old 03-29-2020, 10:01 PM   #113
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

Homemade WRX is offline   Reply With Quote
Old 03-30-2020, 08:34 AM   #114
Norm Peterson
Scooby Specialist
 
Member#: 498642
Join Date: Mar 2019
Chapter/Region: Tri-State
Location: our wrx IS the family sedan
Vehicle:
'19 WRX Limited 6M
'08 Mustang GT (the toy)

Default

Dunno . . . I agree, the part number format looks consistent but I can't make that KW lookup find anything past 350. I suppose it could be a special custom-wound spring, but if you take the 65 and 190 dimensions with four active coils you end up with something more like 650. Not cleanly passing a sanity check.


Norm
Norm Peterson is offline   Reply With Quote
Old 03-30-2020, 08:39 AM   #115
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Mooresville, NC
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

Quote:
Originally Posted by Norm Peterson View Post
Dunno . . . I agree, the part number format looks consistent but I can't make that KW lookup find anything past 350. I suppose it could be a special custom-wound spring, but if you take the 65 and 190 dimensions with four active coils you end up with something more like 650. Not cleanly passing a sanity check.


Norm
Having spent time doing specialized suspension design, a lot of these spring manufacturers have specialized springs not in the normal catalog.

Wouldn't surprise me if it's a special spring.

Last edited by Homemade WRX; 03-30-2020 at 08:49 AM.
Homemade WRX is offline   Reply With Quote
Old 03-30-2020, 09:30 AM   #116
Norm Peterson
Scooby Specialist
 
Member#: 498642
Join Date: Mar 2019
Chapter/Region: Tri-State
Location: our wrx IS the family sedan
Vehicle:
'19 WRX Limited 6M
'08 Mustang GT (the toy)

Default

Quote:
Originally Posted by Homemade WRX View Post
Having spent time doing specialized suspension design, a lot of these spring manufacturers have specialized springs not in the normal catalog.

Wouldn't surprise me if it's a special spring.
Understood. It's just that I can't make 1800 N/mm happen from the dimensions provided. Not even close.

I get why you'd need to run more front spring if you're running little or no anti-dive (kind of where this whole sidetrack started).



On edit, I spent way too many years making and reviewing engineering calculations to not keep trying to make stuff like this make sense.


Norm

Last edited by Norm Peterson; 03-30-2020 at 10:13 AM.
Norm Peterson is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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
Forum Jump

All times are GMT -4. The time now is 04:46 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2020 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.