XRAY - Model racing cars

Hey everyone,

I seem to be getting mixed information on what exactly droop and/or downstop settings are and would love for someone to clarify.

Going by the Hudy manual, I follow the usual setup procedure and set my 'downstops' (at 6mm front, 5mm rear), then my 'ride height' (at 5mm front, 5.2mm rear).

So my understanding of the 'downstops' setting in terms of the hudy setup blocks/downstop guage, is that the reading is 6mm (or 5mm) above the bottom of the chassis. Correct?

So moving on, is this also the setting you use for 'droop' when you go to set it (6mm and 5mm)? Here is where I get confused, because I've heard two things:

1) Your downstop setting is your droop (huh?)

2) I run X mm (the example I hear most often is 3mm front and 2mm rear) above ride height as my droop.

I don't even understand route 1, but it seems real common. Are they saying that they allow the car to travel 6mm (front) and 5mm (rear) before the tires leave the ground?

As far as the second goes - I tried the 'trick' that some people told me on how to set this up - and that is simply put the car up on blocks at the height you want your 'droop' to be. The recommended was 3mm over ride height in the front, so I put the front of the car up on the 8mm step on my guage and adjusted the downstops until the tires were just touching. Did the same for the rear, but at 7.5mm.

Well, as some of you will probably figure out, this limits the travel and changes my ride height. So I'm either doing something wrong, I misunderstood, or the method is flawed.

I would really appreciate if someone could clear this up for me, and give me recommended settings to start at.

Thanks!

Luke

I agree it gets very confusing,the way I read it is if you have the car on 10mm blocks and using a droop gauge you measure the height to the underside of the arm, not sure if it is actually 6mm or 5mm above the bottom of chassis as on the set up sheets it looks like chassis starts at 1mm.
The other way is to have wheels and shocks on (useful in between heats) and measure how far up the chassis travels from standing before tyres are off the surface

This is how it's normally done;



When a sheet says 6 and 5 this is normally what they mean (my drop gauge is also a ride height gauge which explains the numbers underneath the chassis)

When a setup sheet says 2mm or 3mm ORH or 'Over Ride Height', that's where everything is attached and the chassis is carefully lifted up, after it has been raised 2mm etc the tyres will start to lift off the ground.

I think 2mm over ride height is around 7 on gauges, 3mm is 6 on gauges etc.

Hope that makes sense
Skiddins

Skiddins, if these is the case, there is no need to use droop blocks. You just use a ride height tool, which you place under the arm to measure your droop, with the car placed on a flat surface.

Great information everyone, thanks.

Still not totally clear though - I understand the 'downstops' now (the first step of the hudy setup procedure) and the 6mm/5mm.

So what about the 'droop' then (the third step of the hudy setup procedure) and why do you usually only see the downstop setting and not a 'droop' setting?

What do guys normally run for droop in low to medium carpet?

Luke

Droop is the upward and downward travel limit of the suspension. In some contexts it can be referred to as uptravel, or downtravel. Not to be confused with upstop however. Upstop is only a physical addition to the suspension that only serves the purpose of limiting the uptravel to an extent which the suspension itself cannot.

Droop is a crucial setting parameter of a touring car as it adjusts the weight transfer of the chassis.

Droop is directly affected by chassis ride height. When the car is raised off the ground (higher ride height), the droop is reduced. Traditionally there should be a compensation made in the droop setting when big changes to the ride height are made.

When droop is increased, the downstop value measured on the downstop gauge, is of a lower number.

When droop is decreased, the same value is of a higher number.

Thank you!