|
|
|
|
| Author |
|
|
Registered
|
Cage for Coilovers? (Pics)
Experts,
I'm at a cross roads and sick of reading conflicting information. Hoping someone has some information that I cannot find. 1979 SC, 3.6, coilovers, running Nankang AR-1's (not slicks) The car had a weld in full cage but like an idiot I had the front half removed (before I got into extensive track time) The car is flexing something fierce at the moment. You can feel it twisting and hear it popping and creaking under load. My question, if I weld in the front half cage will I gain any structural rigidity to benefit the front suspension? Half the Porsche experts out here in NZ are saying yes, the other half saying the front cage would only be for safety purposes. 2nd question based on the 1st. Do I need to tie a front cage through the dash into the front struts to achieve the rigidity I'm looking for? All sort of threads on the cage subject but I can't find data only opinions. Thanks! Dan     
|
||
06-13-2021, 08:38 PM
|
|
|
porsher
|
In my experience a six point cage stiffened up the tub significantly.
ie A, B and C pillars only: not including the front shock towers How do I know? Well at my home track the front suspension started bottoming out after the cage was installed I concluded that the body flex was absorbing some energy which was not the case after the cage went in.
__________________
86 911 Race Car, with a few 993 bits in the boiler room 79 928 Race Car 88 928 Becoming a Race Car |
||
|
06-14-2021, 11:04 AM
|
|
|
Registered
Join Date: Jan 2003
Location: Langley,B.C.
Posts: 12,002
|
Your front half cage with stiffen the entire chassis significantly.
Cheers
__________________
Turn3 Autosport- Full Service and Race Prep www.turn3autosport.com 997 S 4.0, Cayman S 3.8, Cayenne Turbo, Macan Turbo, 69 911, Mini R53 JCW , RADICAL SR3 |
||
|
06-14-2021, 06:24 PM
|
|
|
Registered
Join Date: Aug 2009
Location: Costa Mesa, CA
Posts: 1,181
|
I’m not saying you need to do this........ but I put a bit of steel in the front of my car..... the chassis is quite stiff now.
 
|
||
|
06-14-2021, 06:45 PM
|
|
|
Registered
Join Date: Aug 2009
Location: Costa Mesa, CA
Posts: 1,181
|
 
|
||
|
06-14-2021, 06:53 PM
|
|
|
Registered
Join Date: Mar 2010
Location: Socal
Posts: 2,384
|
Mine is similar , tied into the upper shock towers and rear front arm mounts .
Are you also tied into the front A-arm mounts Evan ? |
||
|
06-14-2021, 07:16 PM
|
|
|
|
Racer
Join Date: Oct 2010
Location: Franklin, TN
Posts: 5,885
|
This seems to work great for my race car......
__________________
Scott Winders PCA GT3 #3 2021 & 2022 PCA GT3 National Champion 2021 & 2022 PCA West Coast Series GT3 Champion |
||
|
06-14-2021, 07:45 PM
|
|
|
Registered
Join Date: Mar 2010
Location: Socal
Posts: 2,384
|
Scott
I asked for pics before but never got a reply . Is yours tied in all the way from front A-arm mounts to rear engine mounts ? |
||
|
06-14-2021, 07:51 PM
|
|
|
Registered
Join Date: Aug 2009
Location: Costa Mesa, CA
Posts: 1,181
|
Quote:
I’m in the process of tying the 935 camber boxes in the rear into the cage in a similar fashion. The only part of my suspension not triangulated into the cage will be the spring plate pivots. That’s the 1pt. to keep it from being classified as a tube frame car. 
Last edited by Evan Fullerton; 06-14-2021 at 08:20 PM.. |
||
|
06-14-2021, 08:18 PM
|
|
|
Registered
Join Date: Mar 2010
Location: Socal
Posts: 2,384
|
Thanks for the info Evan .
I might yet still have to find time to come look at your car , just to see what it is all about . I think mine is/was maybe not far from being full-space-frame , but it was the engine mounts .. Quite a bit has been removed since then , but it would be interesting for me to see what should be left and what can be removed once the restoration starts to make it back into to a road car . This is just for my knowledge and entertainment though , as I’d rather pay an expert than claim to be one  . Last edited by ian c2; 06-14-2021 at 08:33 PM.. |
||
|
06-14-2021, 08:29 PM
|
|
|
Racer
Join Date: Oct 2010
Location: Franklin, TN
Posts: 5,885
|
Quote:
Yes, it is tied from the front to the back: 
__________________
Scott Winders PCA GT3 #3 2021 & 2022 PCA GT3 National Champion 2021 & 2022 PCA West Coast Series GT3 Champion |
||
|
06-14-2021, 09:30 PM
|
|
|
Racer
Join Date: Oct 2010
Location: Franklin, TN
Posts: 5,885
|
Oh, engine mounts are solid and there is no rear chassis crossmember:
__________________
Scott Winders PCA GT3 #3 2021 & 2022 PCA GT3 National Champion 2021 & 2022 PCA West Coast Series GT3 Champion |
||
|
06-14-2021, 09:35 PM
|
|
|
|
Registered
Join Date: Mar 2010
Location: Socal
Posts: 2,384
|
Thanks for the info Scott .
|
||
|
06-16-2021, 07:53 AM
|
|
|
Registered
Join Date: Sep 2007
Location: Wheaton, IL (Chicago 'burbs)
Posts: 3,141
|
My cage is tied to the front and rear strut towers, from all the experts I'd consulted 15+ years ago this is a necessity with coilovers. Especially in the front, those shock towers were never designed to take the forces of 400+ pound springs. I bet everything up front is flexing. I made sure my cage was tied to all the appropriate places front and rear before ever going to coilovers.
__________________
Ed '86 911 Coupe (endless 3.6 transplant finally done!) '14 Jeep Grand Cherokee 3.0 Turbodiesel (yes they make one) '97 BMW 528i (the sensible car, bought new) '12 Vintage/Millenium 23' v-nose enclosed trailer |
||
|
06-16-2021, 05:20 PM
|
|
|
Registered
|
This thread is what I needed. Going to give the shop these pictures and see what they can do. Didn't want to pull the gas tank but maybe I will to tie the cage into the front.
I've already created a 12 inch crack in the wheel well below the strut mounts. Strut mounts held but the tub didn't. The crack is in place you would never have guessed. I'll post pics when the cage is done! Thanks for the help! |
||
|
06-21-2021, 02:49 PM
|
|
1987 Porsche Targa 3.2
