Daddylonglegs
|
posted on 24/7/12 at 01:06 PM |
|
|
IVA Fail
Oh well, I tried.
Test today at Bristol, Howard the tester was a decent bloke and gave me opportunities to 'tweak' a couple of bits.
Fail points were:
1. Gear lever not radiused to 3.2mm on all surfaces - I'll fit the original Sierra knob
2. Fuel filler pipe not recognised or marked as suitable for fuel, so need new one and paperwork
3. Stick on cable clips on some parts of the loom - will rivet 'P'-clips instead
4. Terminals on ignition coil not covered/protected - boots to be fitted
5. The big one - when service brake is applied the vehicle should not deviate to the left or right, and all wheels of the rear axle must not lock
prior to both wheels of the front axle.
So all-in-all I'm not devasted but P'd none the less
I asked his advice on the brake issue and he suggested fitting one of the limiting valves to restrict the amount of braking on the rear with respect
to the front. He also said to be careful not to reduce the rear so much that it fails the % efficiency test on the rear brakes.
The only problem I now have is once I've fitted a valve, how do I prove it is within limits?
I guess it could have been a lot worse? The best thing was at least I got to drive it in a more 'spirited' fashion so he could see which
wheels were locking up first
Any comments or suggestions welcome guys
[Edited on 24/7/12 by Daddylonglegs]
It looks like the Midget is winning at the moment......
|
|
|
loggyboy
|
posted on 24/7/12 at 01:14 PM |
|
|
Not a bad fail at all.
You could trailer/tow (or drive ) the car to an MoT station to get the brakes tested.
Mistral Motorsport
|
|
owelly
|
posted on 24/7/12 at 01:52 PM |
|
|
Sticky tyres on the back, Teflon Ditchfinders on the front. Then see what locks up first!
http://www.ppcmag.co.uk
|
|
rodgling
|
posted on 24/7/12 at 01:53 PM |
|
|
Different sized master cylinders for the brakes (i.e., fit a bigger one for the rear or smaller for the front to bias it towards the front)? What
sizes are on there at the moment?
|
|
PAUL FISHER
|
posted on 24/7/12 at 01:57 PM |
|
|
Yes not a bad fail, easy enough items, as said above, brake test before retest at local garage, they should only charge a tender.
My first indy I took for a mot before sva just to check things like that.
|
|
britishtrident
|
posted on 24/7/12 at 02:02 PM |
|
|
Before you get too many recomendations on what to do with the brakes it might be an idea to tell us what brake set up you have ie disc or drums on
the rear if drum what diameter, as it might be as simple as fitting smaller bore rear wheel cylinders.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
AntonUK
|
posted on 24/7/12 at 02:45 PM |
|
|
as said get a valve fitted and speak nicely to a local MOT man...
this is what i have,
http://www.burtonpower.com/ap-racing-brake-proportioning-valve-knob-type-cp3550-14.html?utm_source=google&utm_medium=base&utm_campaign=gb_feed
?WbRf=GBase
Build Photos Here
|
|
coyoteboy
|
posted on 24/7/12 at 02:54 PM |
|
|
quote:
Different sized master cylinders for the brakes (i.e., fit a bigger one for the rear or smaller for the front to bias it towards the front)? What
sizes are on there at the moment?
Hang on - assuming independantly leveraged twin cyls, a larger one for the rear will give more pressure at the rear for the same pedal force...
|
|
loggyboy
|
posted on 24/7/12 at 02:55 PM |
|
|
quote: Originally posted by coyoteboy
quote:
Different sized master cylinders for the brakes (i.e., fit a bigger one for the rear or smaller for the front to bias it towards the front)? What
sizes are on there at the moment?
Hang on - assuming independantly leveraged twin cyls, a larger one for the rear will give more pressure at the rear for the same pedal force...
No it doesnt work that way IIRC, the narrower bore exerts more pressure down the line (Think of elephant in stiletos!)
[Edited on 24/7/12 by loggyboy]
Mistral Motorsport
|
|
rodgling
|
posted on 24/7/12 at 03:15 PM |
|
|
As above: Pressure = force / area
So if you increase the area (cylinder bore) for the rear master cylinder, say, you would reduce rear pressure.
|
|
britishtrident
|
posted on 24/7/12 at 03:41 PM |
|
|
quote: Originally posted by rodgling
As above: Pressure = force / area
So if you increase the area (cylinder bore) for the rear master cylinder, say, you would reduce rear pressure.
Or fit smaller bore wheel cylinders, say change from 22mm bore to 19mm will reduce the rear braking force exerted at the tyre tread by about
25%,
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
Daddylonglegs
|
posted on 24/7/12 at 03:50 PM |
|
|
OK thanks guys. Not too upset I suppose, at least I've got a 'to do' list now anyhow.
Not sure about messing with the cylinder sizes etc. as not sure if that would be too fiddly to get right?
The tester said it was marginal but when I took it for a dirve to let him see the lock ups then I did get a little 'step out' on the rear,
and as he said, if that was at 50-60mph or even worse a wet road, I would have been facing the wrong way in an instant!
I have a garage about 400yds down the hill so may be able to tee something up with the guy there to test the efficiency after I have made the
changes.
Any recommendations for the fuel filler hose? I need about 6" of the stuff, and IIRC it is around 60mm diameter.
Cheers,
JB
Forgot to say:
Front brakes - Cortina standard, new discs and pads
Rear - 9" ford Drums with new shoes.
[Edited on 24/7/12 by Daddylonglegs]
It looks like the Midget is winning at the moment......
|
|
whitestu
|
posted on 24/7/12 at 03:57 PM |
|
|
quote:
Not sure about messing with the cylinder sizes etc. as not sure if that would be too fiddly to get right?
You shouldn't need to - by the look of it you are running rear drums and a Fiesta MC. Assuming standard front brakes that should not need
anything else to have some proper F/R brake balance.
Are the front brakes working as well as they should?
Stu
|
|
rodgling
|
posted on 24/7/12 at 04:05 PM |
|
|
I had big problems with this exact issue for ages (MOT and IVA never picked it up, but I had occasional scary moments on hard braking where the back
would step out big time).
Eventually I worked out that the front master cylinder was faulty and not always generating enough pressure, presumably due to the internal seals not
being right. Braking has been great since I swapped it out for a replacement. So that is another possibility.
|
|
britishtrident
|
posted on 24/7/12 at 04:42 PM |
|
|
Forget about using a roller brake test set up for normal MOTs it won't tell you much, the way the IVA test is carried out simulates
dynamic weight transfer.
A road test driving in straight line low speed on a clean dry good tarmac surface will tell you if the front brakes are locking as before
the fronts. To check the back brakes are effective try the brakes at slow speed on gravel you should be able to lock all 4 wheels without too much
trouble.
The 9" drums on the rear of Cortinas can be either Girling or Bendix most were Bendix which don't allow much scope for swapping
out cylinders.
So the answer is a proportioning valve or a simple pressure shut off valve.
With single line to the rear wheels the simplest and cheapest answer is a valve off a production car, the Fiat Strada/Ritmo or Lada Riva valve
is very cheap (about £10) and requires a very simple external bracket added to make adjustable. Once adjusted the adjuster bolt must be
rendered in operable (usually a by bead of weld) before IVA.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
britishtrident
|
posted on 24/7/12 at 04:50 PM |
|
|
BRAKE VALVE / PRV - Pressure Regulating Valve - FIAT PANDA | eBay
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
Staple balls
|
posted on 24/7/12 at 04:59 PM |
|
|
Not a bad fail at all, how does your fuel filler run? If it doesn't turn any corners, I have some pleasantly overkill hose you can have. Will
have to check markings though, as it's marine stuff
Edit: should be okay, is this only 51mm id.
http://item.mobileweb.ebay.co.uk/viewitem?itemId=110409386482&cmd=VIDESC
[Edited on 24/7/12 by Staple balls]
[Edited on 24/7/12 by Staple balls]
|
|
Irony
|
posted on 24/7/12 at 05:05 PM |
|
|
Chin up mate - sounds like a reasonable fail to me!
Where in the IVA manual does it talk about the fuel filler hose and the standards it needs to comply to? I have been looking and cannae find it.
[Edited on 24/7/12 by Irony]
|
|
renetom
|
posted on 24/7/12 at 05:18 PM |
|
|
iva
Hi
Our Indy failed the 1st time because rear brakes were locking up before
fronts, we have a Sunny 1.8GTI M/cyl, willwood callipers at the front & Sierra drums on the back.
The Inspector was very knowledgeable & suggested we fitted a metro Bias valve on the rears.
We did exactly that, and passed with flying colours.
Dont fit an adjustable one , as they are a big no no for the IVA.
Good luck.
|
|
johnwilders
|
posted on 24/7/12 at 06:53 PM |
|
|
Hard luck pall. The fuel filler hose I used has got fuel transfer written down the side, I got it from one of the stalls at stoneleigh I
would'nt want to have to buy a metre tho its bloody expensive. I think I only found two sizes of wheel cylinder for the drums, I went for the
largest ones with this in mind, same set up and no probs. I used the escort non servo duel master but I had it re sleeved cos I had a creepy pedal,
Yes it could a master problem.
|
|
se7en
|
posted on 24/7/12 at 08:33 PM |
|
|
You could always fit a smaller wheel to the front and a larger wheel on the rear and that would do the job
|
|
MsD
|
posted on 24/7/12 at 08:42 PM |
|
|
At least theres nothing too major!
Was it just your fuel filler? or was it also your fuel lines?
and... ive just started sticking my loom in with those self adhesive stick on plastic blocks- look like im going further backwards then forwards
Mark.
|
|
paulf
|
posted on 24/7/12 at 08:42 PM |
|
|
Would it be due to using 9 inch rear drums rather than the smaller escort ones? most people seem to get on successfully with escort drums and cortina
front brakes with out needing a bias valve , the easiest way would be a bias valve as suggested though.
Paul
|
|
Daddylonglegs
|
posted on 24/7/12 at 09:03 PM |
|
|
Thanks for the input guys.
Not really sure where to go to be honest
Don't want to spend another chunk of money especially as the re-test is another £90!
I have searched for threads about bias valves but cannot get a straight answer really. Some folk say bias valve with adjuster permanently welded is
OK, others say no adjustable bias valve of any sort!! I've lloked into master cylinders and repair kits but they seem to be a dark art. Besides
that, the tester did say that the efficiencies were pretty good so I'd be suprised if it was the MC. Can't remember what the front was,
but the rear was 75% and he said for the weight, 60% was the lowest allowed.
All I want to do is sort this damn thing out so I can get my retest booked, I feel further away than when I was waiting for the test
It looks like the Midget is winning at the moment......
|
|
neilp1
|
posted on 24/7/12 at 10:07 PM |
|
|
quote:
2. Fuel filler pipe not recognised or marked as suitable for fuel, so need new one and paperwork
Sorry to hear about the fail. Just out of interest what type of fuel filler pipe was it, as I have some fitted on mine which I'm sure has not
marking on it and the last thing I want is to have to change it as it means stipping off the cage!!!!!
Also I have stuck on some of those tie-wrap bases and tie wrapped the harness in the engine bay. I take it this is a no, no?
Cheers, Neil
|
|