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inboard castor and extra squat??????
clbarclay - 3/4/05 at 04:49 PM

Having realised that there are a few black holes in my knowlage of suspension and handlind I decided to read up on it over the last week whalst on holiday.
Whalst reading I came accross an intersesting point on anti squat, which is to have the axis of the wishbone pivots going through cars center of gravity.

Practically all my experiance of racing cars comes from off-road radio controlled model cars, bellow are 2 examples where they have the complete opposite of anti squat on the front suspension, which should give extra squat.


The top pic below is rwd and has no front breacking. It has about 30degrees (there abouts) of inboard castor. The kingpin is perpendicular to the wishbone.

The bottom one is 4wd and has front breaking from the electric motor. It has 5-10degrees of inboard castor and an extra 5degrees of outboard castor.


These cars can often nose dive from heights up to 20 times or more the height of the car. So is the angle of the wishbones just to give suspension when landing nose first or what? Rescued attachment both small.JPG
Rescued attachment both small.JPG


Northy - 3/4/05 at 05:12 PM

B3 at the top, and Cat at the bottom.

I've got a B4 and Predator (P8 at the mo, just ordered an X10)

Its refered to as kick-up on the front end isn't it? Only refered to as anti-squat on the rear.

I'd think they are totally different beasts been offroad.

Just checked the Pred and it has hardly any kick-up on the wishbones, but quite a lot of camber on the upright.

Do you race then?


clbarclay - 3/4/05 at 05:29 PM

Close but only half a cigar, top ones a B2


haven't raced for a year or 2 know, but used to break wishbones reeguarly before then.


Northy - 3/4/05 at 05:36 PM

Oh yeah, the B3 had different front camber blocks etc


RogerM - 3/4/05 at 06:35 PM

The Pred P8 actually ran anti-dive front geometry.

Not seen the X10 yet but will stay with my own creation, Project Mako

www.roger-candice.pwp.blueyonder.co.uk

not the best quality web site ever, knocked it up one evening a while ago and not updated it since.

I always loved the Pred, was the best of the bunch.

The main reason for running so much kick up on the front of an off road car is to help the suspension deal with the big hits (the ruts would give a 1:1 car a rumble, they are like a cliff to a 1:10). Tourning cars (snooring cars if you ask me) tend to run much less. I run 1 deg anti dive on the front of my Yokomo SD and 4deg outboard castor.

Worcester used to be my club. Raced nationals right up to this year, when I don't intend to ... big car to build!!!

Roger


andylancaster3000 - 3/4/05 at 09:22 PM

You off-roaders.. way too much mud for me. A few excursions off the the black stuff when I was racing my Pan and touring cars was bad enough to clean up!

Bleeding good fun though aren't they!

Andy


Northy - 3/4/05 at 09:27 PM

I love my Pred

The new one will be awesome


NS Dev - 4/4/05 at 07:12 AM

take a look at the various grasser pics in my archive. I race offroad but in something rather bigger!

The rear suspension on my grasser is "pro-squat" in that the trailing arm angle actually sits the rear of the car down as I go off the start line, transferring weight rearwards and also cushioning the shockload on the tyres, helping to stop them breaking loose so badly.

Having said that, some run anti-squat and still seem to go off the line comparably!!

The front end is basically a "locost development" with longer wishbones but using Cortina uprights still, but with modified steering arms, and with an ultra high ratio rack, giving about 0.75 of a turn lock to lock! (great for those opposite lock moments.......well, laps!)