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Author: Subject: It's too low!! (req for advice)
Alez

posted on 16/3/04 at 01:52 PM Reply With Quote
It's too low!! (req for advice)

Greetings from Spain!

I've had the Stuart Taylor Locoblade I bought from Tom for a couple of days down here now, nice. Good news I won't need full approval to get Spanish reg since taking my car here is part of my relocation! No emission test, no cat, no Spanish SVA.

I have a serious problem with ground clearance though. The sump (ST chopped sump) is something like a couple of inches or less off the ground which is clearly a problem for the road and actually it's preventing me from fully enjoying a ride. It looks like I won't even be able to pass MOT here due to the facility used to test brakes and steering. This is definitely something very different from my previous Locost "Isonblade", which had the engine much higher. I really wonder why!! (Different chassis? Different wheels and suspension setup only?)

Currently, the car is on 13" wheels with Yokohama sticky tyres and has the suspension set up for racing. I'm thiking about setting up the suspension for road (parallel wheels, so I get even wear) thus getting a bit extra clearance. Also, I'm thinking about bigger wheels, that would give a bit extra as well plus the wheel does not go as deep into an eventual road hole because of the smaller curvature. The car seems to have quite short gears as it is now, it has an Escort mark II diff, I don't think that 15" wheels would be bad for it, maybe slightly increased clutch wear? The other thing is I'm not sure about the front cycle wings, sure I cannot just put the bigger wheels, should I use the same wings with longer mounting hardware, change everything maybe?

All this comes from my imagination and I have no experience. Also any bits I need I will need to have them sent from the UK, nothing available here. General thoughts? What would you do in my circumstances?

Many thanks.

Alex

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ned

posted on 16/3/04 at 02:00 PM Reply With Quote
alex,

can you not jsut adjust the ride height on the shocks? bigger wheels would help, but might need as you say different brackets etc etc.

Ned.





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Alez

posted on 16/3/04 at 02:28 PM Reply With Quote
Hey Ned!

Didn't know you could modify the height without changing the angle. Sounds like the way to go! Will investigate this weekend..

Cheers,

Alex

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ned

posted on 16/3/04 at 02:38 PM Reply With Quote
Alex,

Use a c-spanner on the bottom spring platform, that should change the ride height if i'm not mistaken. anyone care to correct me? you could always change the springs for longer ones, but check the bump stops and max open length of the shock if you choose to try this.

Ned.





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Alez

posted on 16/3/04 at 03:46 PM Reply With Quote
Cheers Ned, much appreciated.
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JoelP

posted on 16/3/04 at 04:33 PM Reply With Quote
i would do as ned says and srcew the shockers a few times. Another easy thing may be to change the engine mounts for slightly taller ones, or maybe put a spacer in. then the sump will clear a few more things!






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steve wheeler-smith

posted on 16/3/04 at 05:46 PM Reply With Quote
Mot

Being an MOT inspector dont worry about the brake test. If the test center cant get the loco into the rollers they will use a DECELEROMETER this allows the brakes to be tested on a road test. They shouldn't go any faster than 20 mph so they shouldn't get to thrash it (this speed is a set speed layed down by the ministry).
Hope this helps.
Steve

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Jasper

posted on 16/3/04 at 08:28 PM Reply With Quote
Hola mon amigo!!

Good to hear from you.

Bike engine mounts can't be raised like car engines.

I'd go for 15 inch wheels and raised shockers. You may find the extra 1 inch on the wheel will clear the front arches, give them a measure.

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locoboy

posted on 17/3/04 at 03:29 PM Reply With Quote
Alez,

you may be able to squeeze bigger wheels and tyres under there but make sure the wing stays are pretty stiff, ie dont allow the wing to move sideways much, otherwise big bump = tyres catching wing stays = smashed front wings at the very minimum.





ATB
Locoboy

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elitewiring

posted on 17/3/04 at 10:23 PM Reply With Quote
i thought this would be worth a mention, if you adjust the spring platfom height remember to reset the camber, because this will be upset with an adjustment in ride height.
15 inch wheels will give you around 1 inch extra, but ride height adjustment will be cheaper.

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David Jenkins

posted on 18/3/04 at 08:57 AM Reply With Quote
For what it's worth, my Westfield manual quotes approx 6"/150mm ride height front and back, measured from the bottom of the chassis to ground. My engine hangs 2"/50mm below the chassis, so I end up with the usual 4"/100mm clearance.

cheers,

David






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Jasper

posted on 18/3/04 at 10:07 AM Reply With Quote
I raised the back of mine by 2" last night to keep the SVA man happy (clearance of diff to chassis) just by turning the spring platforms. Now 4.5" front, 6" rear.
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Alez

posted on 18/3/04 at 01:10 PM Reply With Quote
Very useful, guys. I was concerned that maybe the Stuart Taylor chassis had a particularly low engine position compared to other BEC builds but from David's post I see it may be similar after all.

Steve, unfortunately "Spain is different" and they won't do that road test. It HAS to go on the rollers they use here.

Hey Jasper, nice to see you around, I'll never forget meeting you + your avatar will always be the coolest ever

Thanks everyone, I now print the thread as usual for some weekend fun..

Cheers,

Alex

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uberf1end

posted on 18/3/04 at 11:06 PM Reply With Quote
Hi Alex,

Glad to hear you have her safely tucked up in her new home, I've been trying to find a new car that would bring me as much pleasure and I think I might have problems.....
I've been to see a Porsche 968 and it felt so heavy and sluggish, same for a BMW M3 I borrowed from a workmate for a lunchtime, I'm starting to think all other cars are going to feel like Mondeos to me now....

Anyway, to the matter in hand.
The sump is slightly reduced in height and the sump plug is flush so it doesn't stick out. However, it could be shortened further or, if you are made of money, The Kit Car Workshop make a billet replacement which is considerably smaller. A friend of mine has just bought one and it is a beauty....as you would expect, however, it isn't cheap at all.

There is certainly plenty of adjustment left in the ride height as it is low at the moment.

As for the wheels, the stays that hold the wings are fairly basic and would be easy enough to replace for additional height but, if you went for bigger diameter, you have to watch the width as any wider than my (your...) wheels and you'll have an issue.

Cheers
tom

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Hellfire

posted on 19/3/04 at 02:23 AM Reply With Quote
uberf1end...

can you make your avatar a bit bigger... I can still see my favourites!

PS Which one r u?






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uberf1end

posted on 21/3/04 at 12:29 AM Reply With Quote
Sorry! I'm going to change it when I can locate what I am looking for....

I am the one at the back on the left (in the poncho)

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Alez

posted on 22/3/04 at 11:23 AM Reply With Quote
Guys,

Any of you have a detailed pic of an upright in your section? I would like to put notes on it and post it here for comments, as I'm quite lost at the moment (I've been having a look this weekend but forgot to take a pic). I'm not sure I can make the car sit higher without making it stiffer, and actually now it's a nightmare to drive on the road, with the suspension so stiff you just jump from place to place with the least road patch. So now I have two problems in one to solve to make it road friendly!

Cheers Tom! I thought the idea of selling the car was actually getting a nice but not so quick car! And now you complain there is nothing quick & affordable out there!

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ChrisGamlin

posted on 22/3/04 at 11:36 AM Reply With Quote
Hi Alex

If the dampers are at the top of their travel then no matter how much you wind up the spring platform it wont go any higher, just harder. Put a jack under the front of the chassis and see how far you need to jack it before the wheels start lifting off the ground. If its only a very small amount and you dont see the damper extending at the same time, then you've already reached the limit of the damper extension.
If you get several centimetres of lift before the wheel picks up, and you can see the damper extending before the wheel picks up then you've still got scope to play with ride height.
If they are already on the limit though, either changing the damper mounting position or changing to longer dampers may be the only way to go
Measure the extended length of a damper and also measure your current ground clearance from the bottom of the chassis rail at the back and front. It may be that you are running correct ride height, but the engine is too low in the chassis.

Chris






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ned

posted on 22/3/04 at 11:39 AM Reply With Quote
Alex,

Could could try changing the springs for softer ones for more grip, less harsh ride, possibly even longer ones to help the ride height if you wished.

all the best,

Ned.





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Alez

posted on 22/3/04 at 02:37 PM Reply With Quote
Excellent posts, Chris and Ned, very clear, I'm starting to realize the way it works now, looks clear in my head, will see in practice when I arrive home..

Many thanks!

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Alez

posted on 23/3/04 at 10:21 AM Reply With Quote
Guys,

I've been re-thinking Chris' post yesterday, I'd like to check that I actually understood well.. Basically, my car is both too low and stiff for the road. When a damper is kept within margin, you can adjust height by turning up the lower spring platform. This should have no effect on how stiff the suspension is. However, if you go up too much, you reach the lenght limit in the damper, and end up with a stiffer setup since you compress the spring. So I'd say my first move should be to check the limit of my dampers. If I've reached it already, I'll loosen the platform and I'll get softer suspension, same height. If I've not reached it, I'll tighten it and I'll get increased height without affecting the stiffness. So I guess I'll just get one or the other, and will need to change dampers and / or springs to get both! The other thing is: is it OK to have the dampers resting at the top of their travel with the spring constantly against them? Is that an option when you want a stiff setup? Are they designed for that or could I damage them by having them hitting their top end?

Cheers,

Alex

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ChrisGamlin

posted on 23/3/04 at 10:58 AM Reply With Quote
Yup I think you are right in what youre understanding!

Basically the damper has a certain length of travel. At maximum/minimum length it obviously cant extend/compress any more so these minimum/maximum lengths in turn determine how far the car's suspension can travel up or down.

All the time there is travel in the damper in both directions, by adjusting the spring platform up you arent compressing the spring any more, just extending the damper, so raising the ride height.

However if your dampers are currently fully extended then all you are doing by adjusting the platform is further compressing the spring (cos the other end of the spring cant move as the damper is already fully extended), making the suspension harder but not changing the ride height

At normal ride height you ideally aim for about 15-20mm of rebound (extending) travel and the rest (probably 30-50mm) in bump (compression) travel, although these can vary depending on damper and setup.

Chris

[Edited on 23/3/04 by ChrisGamlin]






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ChrisGamlin

posted on 23/3/04 at 11:25 AM Reply With Quote
In reply to the second bit, you wont damage the dampers by having them at full extension whilst at ride height, but its not ideal as you then have no ""droop". Imagine driving along with the car and one wheel drops down a pothole, that wheel cant droop into the pothole and follow the road surface as the damper cant travel any further downwards. It also affects cornering, when you corner the inside wheels ideally need a small amount of droop so when the car rolls they still keep in contact with the tarmac, but if there is no droop it can mean a wheel might lift and/or it upsets the car mid corner.

Chris






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Alez

posted on 23/3/04 at 12:32 PM Reply With Quote
Superb Chris, thank you very much, understood each and every word this time

Cheers,

Alex

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