Psycho Warren

iTrader: (5)

Looking at options for when i rebuild the cossie puma.

Now i dont want to go for a standard beam - we all know how shit they are.

So what are the current options?

I was thinking a "stage 3" 6 degree adjustable beam with fabricated arms,

or maybe a WRC type square beam set up,

or most expensively a complete multi-link cradle set up like MK does.

What are peopes views on the 3 setups?? Which is best in terms of trackday handling for a 4wd cossie?

What is the rough costs?

Would one be a better value overall package compared to the other even if it isnt ultimately the "best" handling or most adjustable option?

Who currently makes the muti link set ups??

MK MOTORSPORT

iTrader: (1)

for price I would say 6 degree is the best value for money ,rear cradles are very good but expensive and you have to mod shell ie turrets etc.
mark

Psycho Warren

iTrader: (5)

Im designing the chassis in composite from scratch so its not a problem to "mod the shell" in the design stage as long as i know. With composites i have to laminate in the load spreading metal plates at initial build so i need to be dead set on either a cossie beam set up or a multilink set up as they mount completely differently.

MK MOTORSPORT

iTrader: (1)

HI WARREN
you need to decide which you want to go for ,you could put mounts in for both the you can choose later
mark

Psycho Warren

iTrader: (5)

Which is why im after advice now. less mounting plates= less weight!! so i want to make a choice and get it right first time really.

saph4be

Suppose it all comes down to budget.

Caddyshack

What is so wrong with the std setup and what benefits apart from adjustability do other options give.....out of interest.

Useful thread

MK MOTORSPORT

iTrader: (1)

hi
its the adjustability and the 6 degree geometry of them that make them far superior to standard beams
mark

MK MOTORSPORT

iTrader: (1)

hi warren
if your to a budget then the 6 degree one ,if you have more to spend rear cradle if your budget is sky high lol then go double a arm with inboard rockers and oval tube etc

mark

Ridgey

iTrader: (5)

Caddy shack
Std beams give loads of camber when the rear of the car squats under acceleration, resulting in less grip from the tyre.
That's why lots of people have now fitted modified beams.

Marc sierra

iTrader: (1)

I've made my one 6 degree beam. But if I was in your situation I would go for a McPherson strut (Multi link) like the Escort WRC had. The reason I didn't for my sapph is the fact I don't want to alter the chassis, but if that is no problem the WRC setup would be my choice. I suppose it wasn't for nothing Ford changed this from the Escort Cosworth to the Escort WRC.

I suppose it shouldn't be too difficult either. I would simply use the hubs and struts from a FWD/4WD car and use those at the rear.

Caddyshack

Thanks for the info.....that's the stuff I was after.

Geometry changes that people talk about is the technical fact but it is the "what does it mean to me" that I was after and you answered it.....selling the sizzle and not the steak!

Psycho Warren

iTrader: (5)

I could probably just about design a double wishbone set up but inboard coilovers and push rod suspension is a bit overkill for a saloon car!!

Is that basically similar cradle style set up to MK and addrenaline??

MK MOTORSPORT

iTrader: (1)

Sonic Boom

iTrader: (11)

Pure cnc'd fabricated Porn
Rich

Psycho Warren

iTrader: (5)

whats the big hook things on the front of the cradle front legs??

markk

iTrader: (2)

Longitudinal link bars

cossie rs500

https://www.facebook.com/photo.php?f...type=1&theater

Glenn_

iTrader: (1)

MK thats some serious bit of kit.

jsa

Where does the rear roll centre end up on both the 6ş and cradle ?

Does either end up with different anti squat amounts and to what extent ?

Is the 6ş available with adjustable roll centre ?

nixon_2wd

How would you adjust roll center when the mounting points are the same, jsa?

Psycho Warren

iTrader: (5)

If you want to play with roll centres use this calculator:
http://www.racingaspirations.com/app...try-calculator

Marc sierra

iTrader: (1)

The roll center on a 6 degree beam is lower than on a standard beam. It is not possible to give it more anti-squat as the mounting points would need to be above the floor. The roll center on the WRC setup can more easily be changed by changing where the pick-up points on the cradle are.

jsa

Like this

http://www.e30m3project.com/e30m3per...arm_adjust.jpg

http://www.e30m3project.com/e30m3per...ter/page-2.htm

jsa

By how much ?

Hmmm. What do the Ahmed springs do to the rear ride height ?

nixon_2wd

That setup is pure danger on the street, but perhaps your car is race only.

Marc sierra

iTrader: (1)

By about a factor of 3, since the standard beam is 18 degrees.

Ahmed springs lower it about 1 cm I compared to standard think. But with a 6 degree beam it stands a bit higher at the rear because the arms get slightly longer which means the ratio between distance from mounting point to spring divived by distance from mounting point to wheel gets closer to 1.

jsa

One more, point of adjustment over standard, engineered properly, how does that become so dangerous ?

jsa

By what amount does the static position change, before the dynamic effects of 18 vs 6 come in to effect ?

Marc sierra

iTrader: (1)

I was talking about the static position.

jsa

So your saying the 6ş roll centre is a 1/3 of the height of the OEM 18ş ?

Any of you traders who sell these things know answers to the questions ?

Psycho Warren

iTrader: (5)

the 6 degree beam is copying fords geometry from the race cars, so there isnt much calculation for a trader to do other than producing an accurate jig.

Its when you want to change things further that its useful to understand the impact on the geometry in various states of the suspension.

jsa

Thing is, there are quite a few different race car beams, a couple different squares, some modified round ones and the WRC cradle.

All have different geometry, so choosing which to use would be a lot easier if the geometry was understood.

Sure the sellers on here are copying but which geometry have they copied, and are they tweaking it ?

Having looked through a lot of posts on the 6ş beams there are visible differences between the various beam makers. Question is how much of that is different geometry ?

The answer to your initial question would be much easier to understand if the geometry was explained.

Frankly I don't think it is too much to ask for the traders making these things to know the product they sell.

Personally I'm looking to purchase an adjustable rear beam, which type and who's is difficult to nail down.

MK MOTORSPORT

iTrader: (1)

hi
what geometry are you looking for .what is it you want the beam too do ,a 6 degree beam is just that 6 degree ,there are no other changes to it other than adjustment for camber and toe, and if its double adjustable the ability
too move the wheel in the arch ,the 6 degree alteration slows down the camber change for a given travel of the rear suspension , the rear cradle is a different ball game ,that can be adjusted in more ways

mark

markk

iTrader: (2)

The wrc style cradle on mine has even longer lateral links than the escort wrc setup.

Jay,

iTrader: (4)

Speak to these people

http://www.dewitts.co.uk/wrc-gpa-rear-suspension.html

Caddyshack

Looks nice and shiney....gotta be good? I like it

markk

iTrader: (2)

Lol they could sell you anything grpa or wrc but orob tell u no more about geo than this forum

MK MOTORSPORT

iTrader: (1)

hi mark
thats even better slows down the changes even more ,but best setup is double a arm with inboard rockers ,you can build in anti squat ,alter the ratio of wheel travel per shock travel,reduce unsprung weight build in camber change etc etc

mark

Jay,

iTrader: (4)

Then every one is fucked Most people are hung up the grp A/N setups or worse camber shims and ahmed springs is god lol