Too Low

Murray Cowley · 07-24-05, 04:13 PM

I reckon my KVA is too low, how would I go about adjusting the ride height?
Thanks
Murray

Murray Cowley · 07-24-05, 04:14 PM

Front

Murray Cowley · 07-24-05, 04:15 PM

Peter D · 07-25-05, 06:48 AM

Murray, I think you are right - the front could do with maybe 1/2" & the back with 1". It all depends on what coil-over shocks you have - mine are UK AVO's & are easily wound up or down by turning the lower spring plate with a C-spanner. If you can show a pic of the shocks, I'm sure that plenty of experts on the site will be able to give you the clues.

BTW, you will need to re-do your wheel alignment after such a major change in height - I was surprised at how much mine went out after a similar change.

Kind Regards,

Peter D.

Murray Cowley · 07-26-05, 07:24 AM

Peter thanks for the reply, I thought that would be the solution but would that not alter the spring settings too, make it harder?. The coil overs are Spax M73A front and rear, not a clue as to the spring strength/poundage? Obviously as you can see from the phots, the rear suspension units are not bolted in place properly yet, that may make a difference too!! Lots of things to do and think about yet. Any suggestions welcome.
Cheers
Murray

Murray Cowley · 07-26-05, 07:30 AM

Front end

Howard Jones · 07-26-05, 09:49 AM

Use the adjustments on the shocks to set ride height at 5" at the front and 5.5" at the rear. Have a look at it after and post a picture. Make your measurment at the point on the chassis frame rails that is nearest to the pavement. Same point on both sides of car. Make sure you do this on level ground. This setting will get you close and as you learn more about your car you can fiddle with it.

Does anybody think that those shocks look short? Anyway give the above a try. While you are at it measure the lenght of the shocks fully extended and again fully closed. Center of top eye hole to bottom eye hole. You might need these measurements later and they are easy to do now. Also measure the lenght of the springs unloaded and off the shocks. Take pictures of both. You might need them later also.

Also it is helpful to keep a log book on chassis situps. This could be you first entry!

John W · 07-26-05, 10:59 AM

I would say it is the springs that look too short.
It almost looks to me like the car is sitting on its bump-stops...

Murray Cowley · 07-26-05, 03:37 PM

Thanks for the suggestions chaps, I shall try to have a go at setting the ride height, measure shocks/springs etc as per your post Howard, may take a bit of time though, and start a log book too. Good idea that. Better go and do some real work now. Will post again when I get some results. Thanks again
Murray

Kalun D · 07-26-05, 07:42 PM

It also looks like a very low profile rear tire. Like a 35 series or something. That's ok as long as there was a corresponding increase in rim diameter.

You may want to look at the height of the tire compared with the tire height that the chassis was designed for, as that will affect your ride height.

Murray Cowley · 07-27-05, 01:41 PM

Kalun_D,
hi mate, yes the tyres are low profile, front at 215-45-17's and the rear 245-40-17's. I hadn't thought about the tyres. I believe this car was originally going to be a track car so needs to be sorted for the road.
Thanks
Murray

daveb · 07-27-05, 07:44 PM

Hi murray
what steering rack is fitted? I have used a mk2 escort rack with extensions, but to reduce the bump steer i have relocated the rack further back, from your front end picture it looks like your steering arms are angled forwards. mine ended up almost straight when viewed from above. worth checking now while its still movable!!
dave b

Murray Cowley · 07-28-05, 11:45 AM

OOh No, something else to think about!! I havn't a clue what rack is fitted. Since I have got it down here and into the carcoon, it's been pretty wet, I'm not taking the cover off if it's raining!! I have an old MG which needs me to finish a major overhaul yet before I can start on the 40 but I cannot resist trying to sort things out now! Her Indoors is a bit more logical than me, get one thing finished first say's she. Ah well, I can fiddle a bit!!
I shall see if there are any distinguishing marks to identify the rack, any hints? Come on the sunshine!!
Murray

Kalun D · 07-28-05, 12:19 PM

""to reduce the bump steer i have relocated the rack further back""

Front to rear movement of the rack does not change bumpsteer.

Up and down movement of the rack or the outer tie rod end location on the upright are some of the things that affects bumpsteer.

Front to rear movement of the rack does affect ackerman. Sometimes, depending on upright steering arm angle, a little angle to the steering tie rods is necessary for proper ackerman.

Brett James-McCall · 07-28-05, 12:43 PM

Murray,
You'll probably find it may be either a Cortina or Escort rack. Can you measure the width where the bushes go, I'll be able to tell you from there.

Brett

Murray Cowley · 07-28-05, 03:07 PM

So the rack is ideally pretty central to the wheels,? is that right Kalun-D?
OK Brett, will do as soon as I can.
Thanks everybody,
Murray

Tom Hudson · 08-05-05, 06:51 AM

I think Kalum may be incorrect when he says that moving the rack backwards does not affect the amount of bump steer. On original GT40s and the C type KVA the front wishbone to chassis mounting points are not parallel in plan view. Therefore if the steering rack is moved rearward the effective rack length will shorten and vice versa .This will affect the amount of bump steer in exactly the same way as shortening or lengthening the Rack.

I notice that Kalum has a scratch built chassis for his KVA body so maybe his suspension mounting points are parallel, as in a Tornado or GTD chassis, in this case he would be correct.

Tom