Ride height

[Harry Flatters]

I only have a very basic understanding of car set-up, so can someone please explain this to me?

 

As I understand it, the perceived wisdom when setting the front ride height is that the wishbones should be parallel. If this is the case, are there any other valid settings for the RH (which would mean that the wishbones are not parallel), namely to give a tad more sump clearance, especially when running slicks?

 

What effect would having the wishbones NOT parallel have on handling?

 

*arrowright*Harry Flatters *arrowright*

AKA Steve Mell - Surrey AO and Su77on Se7ener

Carbon Components from IK9 Composites

[Normans_Ghost]

Steve, The ride height and wishbones being parrallel are not directly related.

 

I had the spacer on the wide track on the wrong side of the wishbone which affected steering (cornering). I've now fitted 2 spacers and my lower wishbone is parallel.

 

If you have an adjustable platform the ride heights are linked to corner weights. I would suggest you book it in with Gary May (Freestyle) for corner weight/ride height setup.

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

[Harry Flatters]

I think I may have used the word parallel when I really meant horizontal. I believe the wishbones should be parallel regardless of what angle they sit at.

 

*arrowright*Harry Flatters *arrowright*

AKA Steve Mell - Surrey AO and Su77on Se7ener

Carbon Components from IK9 Composites

[Normans_Ghost]

I took your parrallel as meaning horizontal.

 

If you want to see photos of before and after I'll send them.

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

[I.Mupferit]

I may be wrong here but the wishbones aren't parallel are they 🤔

 

Gary May told me to aim to get the bottom wishbone parallel with the ground or put another way, horizontal which means the upper wishbones are pointing slightly upwards.

 

Steve have you got Freestyle pushrod suspension?

 

Brent

 

2.3 DURATEC SV. In the final weeks of gestation. SVA booked/postponed/booked/postponed/booked.

[Harry Flatters]

Brent you may be right about just aligning the bottom one parallel with the ground. So I guess my question is, if I don't have sufficient clearance with the lower wishbone parallel to the ground, what is the effect of increasing clearance and having the lower wishbone pointing slightly down.

 

My suspension is just the normal widetrack.

 

*arrowright*Harry Flatters *arrowright*

AKA Steve Mell - Surrey AO and Su77on Se7ener

Carbon Components from IK9 Composites

 

Edited by - Harry Flatters on 20 Apr 2005 13:20:40

[Dannyboy]

Steve..

 

I think the main difference in raising the ride height comes from raising the centre of gravity of the car.

 

If you raise the front without raising the rear the same amount you'll also change the weight distribution of the car which will affect handling. But the only difference i noticed was that turn it was not as crisp with the higher suspension height and *perhaps* a tad more roll....But that's a small price to pay against scraping the sump etc every five mins 😬 😬

 

Dannyboy

[Mick Day]

Steve

 

I don't think having the bottom wishbone pointing down is going to make much difference to handling. In an ideal world, parallel to the ground, is the place to start & means one has to accept whatever ground clearance one gets; on a smooth track one can go quite low. However unless you want to be winding it up & down for track & then road set the front ride height which gives YOU the sump clearance YOU want then work from there. The rear ride height can then be set about 15mm higher than the front. However a flat floor set-up with Gary is well worth the money.

 

You mention tyres & of course different profiles will give different ride heights. So you could set the ride height YOU are comfortable with for your slicks & your road tyres should give increased clearance for the potholes of Surrey!

 

Edited by - Mick Day on 20 Apr 2005 17:50:17

[Normans_Ghost]

Measuring from in front of the rear wheel (point where rear wing is fixed at bottom) to the centre of the two engine mounting bolts should be 10mm according to Gary.

 

I settled on 145mm at rear, 135mm at front and cut two bits of cardboard as measuring "sticks".

 

I got a weight equivilant to me (4 sacks of spuds, 2 full petrol cans and 2 cans of 4ltr oil!) on the drivers seat and set the height as above all round. I then adjusted the rear platforms to get equal weight on front wheels.

 

It will be better on Gary's setup but the chap who normally does mine in Chesterfield is now into the race season.

 

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

[Dobuy]

I came up with a cunning and soon to be patented ride height measuring system. (unless someone has done it before that is!)

Buy yourself a cheapie telescopic magnetic pick up tool, (with a screwdriver type handle).

I ground off half of the handle using a bench grinder, so the end was flat.

Put magnetic tip at your measuring spot on chassis, and extend to touch handle on ground

Sit in car

Get out of car and measure resulting length of magnetic tool using vernier gauge or ruler

 

If you are really rich and can afford £ 4.80, for 4 tools you could do the whole car at once !

 

Works really well and saves depriving innocent Paddies from their spud supplies

 

Duratec Se7en SV, built in Dubai, pics here!

[oldbutnotslow]

This is something that has been exercising my humble brain lately and having spoken to Simon Lambert at CC on a number of occasions I believe that I now have a better understanding of what’s going on and the following is based on the information that I have been given.

A change to wide track and to 250/215lbs race springs is what has prompted this.

 

To start with CC were a little bit airy fairy saying well is how you like it but that was not going to be good enough for what I needed so I persisted and continued to question over a couple further conversations after I had give my two brain cells time to mull things over after each conversation.

 

Ok and I will stand to be corrected by those more knowledgeable, the front ride height for track use will be around 11.0 to 12.5 cm when measured under chassis directly under the front engine mount on the drivers side on a right hand drive car and in the same place on the other side.

 

You will need to measure this on the other side as the N/S engine mount on a RHD car is set further back. You may want to set the ride height a tad higher for road use. The rear height, measured again under the chassis, is taken on the chassis directly under the front of the rear wheel arch. The standard set-up suggests 15 mm rake [higher at the rear] but for some tracks you may want this lower ie twisty circuits (I ran mine previously at 5mm rake but then again I wind up wearing big flats on the rear A bracket N/S bush!!)

 

The lower front wishbones should be as horizontal as you can get them when measured with a spirit level. (remember to settle you car by bouncing up and down a couple of tines front and back) However, this may compromise the 11 to 12.5cm clearance.

 

This is where it starts to get a bit more personal and you do need to be mindful of sump clearance as well. Sump clearance should, it is said, be between 6 to 7cm and again it depends on the use and the weights being put into the car.

Being generously proportioned I want my set-up to be that with me in it!!

 

 

Corner weighting is a whole different subject. If you haven’t had your car corner weighted (AKA Flat flooring) it is something as has been said that will transform the handling. However changing your tyres pressures is enough to change the balance of the car never mind ride height, different sized tyres toe in camber or different springs!

 

Each time you mess with something like this you should in theory flat floor your car again.

 

However the reality of this is that we are never going to be that exacting so a good compromise is what is called for both in terms of the ride height and the flat floor set up.

 

I really hope I have not spouted a load of bo[[ocks here 😳 as this will be how I set my car up this weekend as I have access to a set of Longacre computer scales and will be flat flooring my car as well as setting the ride height.

 

 

Grant

 

Black and stone chip.

Engine now running (thanks Oily!) Got the first 180 miles under my belt

here

[sjmmarsh]

Before I got my seven, I spent a few years racing radio control buggies. Great fun, and a good way of learning about suspension setups as a good r/c car will behave in a similar way to a real one. It is also a lot quicker to run a few laps to test any setup changes and then restore the settings if it didn't improve things. This only takes about 10 mins, so you learn pretty quickly.

 

The other good thing about r/c racing is that there are plenty of tuning guides available on the web: A good one that discusses ride height is here (page 16/17). The rest of it is quite relevant to seven setup as well.

 

Just remember that a buggy is made to run off-road and be able to absorb jumps. Mine would run at 25mph flat out and easily land jumps from a height of 50cm or so without grounding the suspension - equivalent to a real car that does 250mph and can clear 5m obstacle... hence the importance of suspension droop!

 

Steve

 

Steve

[Harry Flatters]

Cheers for all the replies guys. Looks like a visit to Gary may well be on the cards 😬

 

*arrowright*Harry Flatters *arrowright*

AKA Steve Mell - Surrey AO and Su77on Se7ener

Carbon Components from IK9 Composites