TIP Engineering Forum Index TIP Engineering
Theory In Practice
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Shock dyno tech article

 
Post new topic   Reply to topic    TIP Engineering Forum Index -> Good Vibrations
View previous topic :: View next topic  
Author Message
Wiisass
Head suspension nerd


Joined: 09 Nov 2005
Posts: 131
Location: Philly

PostPosted: Tue Jan 31, 2006 11:33 am    Post subject: Shock dyno tech article Reply with quote

This is the tech article I wrote about our (FSAE) new dyno and the testing I've done. There's some good info on there on basic dyno stuff and testing and understanding the results. All of the specific stuff in there relates to the dampers that we're using or have used in the past on the FSAE car.

www.theoryinpracticeengineering.com/tech/shocks.pdf
_________________
TIP Engineering
Just put the TIP in.
R&D, damper development and fabrication.

jrud@tipengr.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
MistaTwo



Joined: 09 Mar 2007
Posts: 18
Location: Pittsburgh, PA / London, England

PostPosted: Mon Mar 12, 2007 4:29 am    Post subject: Reply with quote

What was your overall opinion of the Cane Creek's on the car? We're currently running Ohlins ST44's on one of our cars, and Rissi Racing dampers on the new one. However, the Rissi's were shockingly terrible on the dyno, and the Ohlins are massive, so we were looking into the Cane Creeks. I'll be reading the paper you have posted later today so hopefully that'll provide some more insight into it
Back to top
View user's profile Send private message AIM Address MSN Messenger
Wiisass
Head suspension nerd


Joined: 09 Nov 2005
Posts: 131
Location: Philly

PostPosted: Mon Mar 12, 2007 12:32 pm    Post subject: Reply with quote

I couldn't have been happier with the Cane Creeks despite the cost. I was a little worried about them being too stiff for the springs we wanted to run (225/250), but they worked out fine. After tuning them, the damping ratios ended up a little higher than I anticipated which worked out perfect for the dampers. Adjustments on the dampers were consistent and well defined.

I used the Risse's the two past year and I was never happy with them. They didn't seem to do anything right. They're fine when there are other things with your setup that need improvement. But when you get to the point where your shocks are holding you back, they really aren't worth it. Unless you want to make shims and pistons in house and spend way too much time on the dyno, I don't think they're worth the effort.

If you need any additional plots other than what are in that paper, let me know. I spent a lot of time on the dyno with both these and the Risse's.

Tim
_________________
TIP Engineering
Just put the TIP in.
R&D, damper development and fabrication.

jrud@tipengr.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
MistaTwo



Joined: 09 Mar 2007
Posts: 18
Location: Pittsburgh, PA / London, England

PostPosted: Mon Mar 12, 2007 3:26 pm    Post subject: Reply with quote

yea yea the Risse's were horrendous when we put them on the Dyno. The Ohlins were absolutely gorgeous, but they are quite big and heavy, with the remote resevoires too. We've been looking in to the Cane Creeks cause it seems to be the best of both worlds. But yea, if you could send me whatever you have on the Cane Creeks, that would be fantastic. Right now its pretty much down to either:

A: making our own in house
B: the Cane Creeks or
C: reusing the Ohlins.
D: somehow making some penske 3-ways from a sportbike work, even though they are gigantic

but its good to know you thought they were really good. for us over in england, the price isnt a huge deal because of the exchange rate. did you run them with the steel springs or the ti springs? sorry, lots of questions, but hahaha thats the whole point of the forum. thanks again man!
Back to top
View user's profile Send private message AIM Address MSN Messenger
MistaTwo



Joined: 09 Mar 2007
Posts: 18
Location: Pittsburgh, PA / London, England

PostPosted: Tue Mar 13, 2007 10:15 am    Post subject: Reply with quote

im also seeing alot of hysterisis at the beginning of the graphs. did you notice that when driving or tuning them?
Back to top
View user's profile Send private message AIM Address MSN Messenger
Wiisass
Head suspension nerd


Joined: 09 Nov 2005
Posts: 131
Location: Philly

PostPosted: Tue Mar 13, 2007 12:03 pm    Post subject: Reply with quote

Do you have the Roehrig software? I can send you a bunch of the files for that software and it will probably be a lot more beneficial for you than to just send you jpg captures of the plots.

For the springs, we had Draco make us springs. Cane Creek didn't offer a spring with a rate less than 300lb/in, which was too stiff for us. The springs were steel, I had looked into Ti springs, but they were a little too expensive for us to budget in.

We also tried going with the Shock Shop Ohlins setup, but we couldn't find a way to package them without changing a lot of things.

As for the plots, I don't think that is hysteresis, it's due to the way the pressure builds inside the damper during a crank dyno test. It also only really happens as the bleed orifice gets closer to being closed off. And we also never ran the shocks that stiff, so I can't say how it felt on the car at that setting.

Tim
_________________
TIP Engineering
Just put the TIP in.
R&D, damper development and fabrication.

jrud@tipengr.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
MistaTwo



Joined: 09 Mar 2007
Posts: 18
Location: Pittsburgh, PA / London, England

PostPosted: Wed Mar 14, 2007 4:30 am    Post subject: Reply with quote

sadly i do not have the software, but i will ask around today to see if we can make use of it somehow. but thanks for all this, it is really helping with damper selection for next year. i'll let you know today or tomorrow if we have the software somewhere. thanks again!
Back to top
View user's profile Send private message AIM Address MSN Messenger
Wiisass
Head suspension nerd


Joined: 09 Nov 2005
Posts: 131
Location: Philly

PostPosted: Wed Mar 14, 2007 1:17 pm    Post subject: Reply with quote

You can download the software from the Roehrig site.

http://www.roehrigengineering.com/cart/pages.php?pageid=2

I'll throw a some of the test files up on the site a little later tonight, once I get home. I have some low speed and high speed sweeps that show the adjustment range of the dampers.
_________________
TIP Engineering
Just put the TIP in.
R&D, damper development and fabrication.

jrud@tipengr.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
Wiisass
Head suspension nerd


Joined: 09 Nov 2005
Posts: 131
Location: Philly

PostPosted: Wed Mar 14, 2007 4:42 pm    Post subject: Reply with quote

http://www.theoryinpracticeengineering.com/tech/canecreek/

I just threw up some of the tests. There's two folders in there, most of the files are Roehrig files and then there are word documents with notes in them.

Tim
_________________
TIP Engineering
Just put the TIP in.
R&D, damper development and fabrication.

jrud@tipengr.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
MistaTwo



Joined: 09 Mar 2007
Posts: 18
Location: Pittsburgh, PA / London, England

PostPosted: Fri Mar 16, 2007 9:22 am    Post subject: Reply with quote

thanks alot man. the software is downloading as i type this, so i'll take a look at it all later this weekend. ill let you know if i have any questions about it sometime next week then. but this is really really useful i cant thank you enough for this!
Back to top
View user's profile Send private message AIM Address MSN Messenger
Display posts from previous:   
Post new topic   Reply to topic    TIP Engineering Forum Index -> Good Vibrations All times are GMT - 5 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group