Foaming the chassis

[fabianyee]

the Strut towers are not part of the chassis??

There is more to it. Similarly, bigger anti roll bar will lessen you car's grip. But then again, these are ALL suspension tweaks.

Antiroll bar is suspensioin tweak. Anti roll bar decrease bodyrolls.
Again your statement is partially true. There is an optimum stiffness to the antiroll bar for the car to achieve the balance between body roll and traction. When it's TOO STIFF the grip lessens at the corner. Get it right and it'll do wonders. I've tweaked the settings on the Ireland Engineering anti roll bars so I know what settings works and what not.

Again, u still haven't presented your case. Experience on both this issue is much appreciated. I know u've been dabbling with the RC chassis. but not everything can be translated to real life use on a full scale vehicle.

 

[E46Fanatic]

Originally posted by Twin_Sparx@Feb 15 2006, 10:37 AM
Hope this clarifies the argument, and you guys enjoyed reading it as much as I enjoyed regurgitating it out.

I enjoyed reading it... Excellent stuff and it was very nice of you for sharing your domain knowledge with us enthusiasts in the forum.... I hope to meet you one day to BS more in this area... and I promise I'll buy you a few nice cold beers in the process...

BTW, what software and systems do you run your FEA on? Just curious...

 

[Twin_Sparx]

Originally posted by E46Fanatic@Feb 16 2006, 02:20 PM

BTW, what software and systems do you run your FEA on? Just curious...

A beer treat is most welcome indeed, thanks!! :yes!:

Pre and post processing of the model & results were done on an HP Pavillon workstation running HP-UX v11. Softwares were Altair Hyperworks and LS Pre/Post from LSTC.

The solver was LS-DYNA v970 running on a 16-CPU Dell linux cluster with Intel Xeon chips.

Why the interest? :blush:

 

[E46Fanatic]

I'm quite a tech geek thats why..heh :blush: . We are in the business of supercomputing on demand and have done work with parties for vehicle crash simulation among some of our business in this area. Primarilly used LS-Pre/Post and LS-Dyna on a portion of a 120 node IBM Linux cluster with dual AMD Opteron64s per node. Also doing visualization in our viz lab with IBM's Deep Computing Visualization (DCV).

I think you have a fantastic job... I find it fascinating

 

[ALBundy]

Originally posted by fabianyee+Feb 16 2006, 02:42 AM-->QUOTE (fabianyee @ Feb 16 2006, 02:42 AM)

 

[The Necessary]

Aiyah, who cares about how stiff your chassis is when you're too light to flex it?

I guess chassis stiffness does matter to those who're more generously endowed! Hahaha!

 

[fabianyee]

Originally posted by ALBundy@Feb 16 2006, 04:00 PM

Strut bars will not improve the grip level as you claimed and neither will it improve handling substantially. Basically the two shock towers are in unison under hard cornering and would probably help to prevent them from collapsing under severe cornerings (if the chassis aint strong enough).

A stiffened chassis will cause the car to lose its grip easier especially when the road surface is uneven. Tire contact with road surface is lesser compared to one with a softer chassis and hence lesser grip.

still waiting for u to present ur case/experience...

 

[kevster30]

Stiff chassis:

1) on our 'wonderful' civil roads: it would reduce grip as the chassis and suspension components would be 'fighting' against oscillation(movement) to try and maintain the optimum contact patch. Stiffer chassis on-road will cause the car to become 'skittish'. How do I know? try driving a track prepped car on our roads. It will be darting and bouncing all over!

2) on the track: it will ensure a consistent contact patch IF the rest of your suspension is set-up optimally. Hence, stiffer chassis would promote better grip(if your suspension is properly tuned to the conditions) Why else bother with roll cages and strut bars and double-seam welded chassis?

To surmise this 'discussion' on foaming, I recommend that BOTH Lee and the Necc be taken out back and foamed. Then 3-4 days later, subject them to the independent laboratory tests at PNDC with Dr. Zoggee as testor! HOW?

 

[The Necessary]

Na, I think we should take Kev's foamed up ride and smash it into an e36 to see if the foaming makes any difference.

 

[kevster30]

Originally posted by The Necessary@Feb 16 2006, 03:44 AM
Na, I think we should take Kev's foamed up ride and smash it into an e36 to see if the foaming makes any difference.

But, but, I just tried a little of it on my side sills and not the whole hog like Lee!

Besides, why you wanna waste a nice car like an e36? :rofl:

 

[The Necessary]

Originally posted by kevster30+Feb 16 2006, 03:50 AM-->QUOTE (kevster30 @ Feb 16 2006, 03:50 AM)

 

[kevster30]

Hehehehehehehe!

 

[flash]

Originally posted by kevster30+Feb 16 2006, 04:50 PM-->QUOTE (kevster30 @ Feb 16 2006, 04:50 PM)

 

[Alvin]

Aiya just foam your little birdy & see if the stiffening helps. Can use some side gforce also to determind if you skid or loose traction. Whats this thread about again? kekekekekkekekekekekke

 

[kevster30]

Originally posted by flash+Feb 16 2006, 04:15 AM-->QUOTE (flash @ Feb 16 2006, 04:15 AM)

Originally posted by kevster30@Feb 16 2006, 04:50 PM

 

[kevster30]

Originally posted by Alvin@Feb 16 2006, 04:18 AM
Aiya just foam your little birdy & see if the stiffening helps. Can use some side gforce also to determind if you skid or loose traction. Whats this thread about again? kekekekekkekekekekekke

Hahahahahaaaa! :rofl: :rofl: FOAMING UR DIDDY! Hahahahahaaha!

 

[ah lian]

h34r:

 

[Zoggee]

Originally posted by pussy@Feb 16 2006, 02:44 PM
wow.. 14 pages..

my input and results..
foaming the chassis.. well did it during the recent holidays..

handling ? my current suspension could not take it... on the fast road and sweeping corners...( based on my curent engine conversion, not before it B18 )

solution ? changed the springs and dampers... car handles much better and a firm ride.. 180km/h in sweeping corners to Bukit kayu hitam..

effects ? the road noise is reduced, going over humps is stiff and solid thud on the suspension..

if accident ? no idea, have to wait and see.. zoggee ? crash pilot ?


regards.

Yes...!!!! B)

test whos car....??? crash whos car..???? :nyehehe:

 

[Zoggee]

Originally posted by E46Fanatic+Feb 16 2006, 03:50 PM-->QUOTE (E46Fanatic @ Feb 16 2006, 03:50 PM)

 

[Zoggee]

Originally posted by kevster30@Feb 16 2006, 05:48 PM
Stiff chassis:

1) on our 'wonderful' civil roads: it would reduce grip as the chassis and suspension components would be 'fighting' against oscillation(movement) to try and maintain the optimum contact patch. Stiffer chassis on-road will cause the car to become 'skittish'. How do I know? try driving a track prepped car on our roads. It will be darting and bouncing all over!

2) on the track: it will ensure a consistent contact patch IF the rest of your suspension is set-up optimally. Hence, stiffer chassis would promote better grip(if your suspension is properly tuned to the conditions) Why else bother with roll cages and strut bars and double-seam welded chassis?

To surmise this 'discussion' on foaming, I recommend that BOTH Lee and the Necc be taken out back and foamed. Then 3-4 days later, subject them to the independent laboratory tests at PNDC with Dr. Zoggee as testor! HOW?

huh..?? since when I become a Dr.??? :unsure: