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a day of mixed emotions..

7 Jan 2008, 2:55pm
Whilst i'm sat in a verge killing time, I thought I'd write a very brief precis of today's fun and games. I got up good and early, and in convoy with my father i drove to the sva station. The car seemed fine and the test went well. A few complementary words from the inspector, and a couple of simple failures - all very pleasing. The drive home was going well - I called in on a friend to pick something up and my old chap went his own way..... This was an error - after travelling 5 miles down the road, I heard a nasty rumble, so pulled over. The problem appeared to be os outer cv so I decide to get back in, and limp home. Great plan, right up until the point I released the clutch, when I was greated with a nasty bang and no drive....
7 Jan 2008, 3:13pm
Hope all is well and its a quick easy fix without too much damaged or exspence. Any idea why it failed?

All the best

Jon
7 Jan 2008, 3:21pm
Is that the SVA failure or the CV joint you want to know Jon.

For a CV to fail to no drive would mean its almost dangling free, hope its not a bigger problem.
7 Jan 2008, 4:17pm
Sorry to hear that, hope its not too big a problem and you'll be back through of SVA with a pass soon.
7 Jan 2008, 4:24pm
John

Hope all goes well with the repairs, and you get underneath what caused it, I know some of the Turbo boys have had issues with drive shafts in the past.

Sounds like the SVA was on the whole good, hope the issues are an easy fix.

Steve
7 Jan 2008, 4:51pm
Okay, a proper response, now I'm not fighting to type on a mobile phone keypad.

SVA failure points:

Projections - diffuser edge radius, rear clam edge radius, and no mesh in the main front clam vent (thus allowing the knee device to get in and touch non conforming surfaces).

Bolts - a couple of suspension bolts don't expose enough turns beyond the nut top.

that's it for the SVA

Not sure on the CV - just stuffed the car back in the garage for the moment, but I will have a look later, as I'm exceptionally curious. I did note some grease had been flung from the CV, and the shaft was hot.... doesn't bode well.
7 Jan 2008, 4:58pm
alackofspeed wrote:
Okay, a proper response, now I'm not fighting to type on a mobile phone keypad.

SVA failure points:

Projections - diffuser edge radius, rear clam edge radius, and no mesh in the main from clam vent (thus allowing the knee device to get in and touch non conforming surfaces).

Bolts - a couple of suspension bolts don't expose enough turns beyond the nut top.

that's it for the SVA

Not sure on the CV - just stuffed the car back in the garage for the moment, but I will have a look later, and I'm exceptionally curious. I did note some grease had been flung from the CV, as the shaft was hot.... doesn't bode well.



Hi mate,

I had a drive shaft problem once on my road 5Exi - it would just 'pop-out' randomly.. It would happen if I took a right handed corner with a vengence..
Turned out that the shaft I was using was not the correct one - the stupid thing looked identical but when put next to the correct one it was about 1/4 inch too short.. So it would randomly snap out of place..

Worth checking..

Dylan
7 Jan 2008, 5:09pm
some pictures of the day.....







7 Jan 2008, 5:20pm
(refering to 2nd to last picture) I thought you were going to wash it :tape:

Must have been nice getting it on the road though even if you did have some problems. What SVA centre did you go for, it looks like you'd done some miles on the journey. Sounds like you had a relatively friendly inspector (unlike some of the tales you hear) and at least the failures dont sound too bad to correct.
7 Jan 2008, 5:30pm
dylanp wrote:
Hi mate,

I had a drive shaft problem once on my road 5Exi - it would just 'pop-out' randomly.. It would happen if I took a right handed corner with a vengence..
Turned out that the shaft I was using was not the correct one - the stupid thing looked identical but when put next to the correct one it was about 1/4 inch too short.. So it would randomly snap out of place..

Worth checking..

Dylan



John's Shafts as are all of the type r builders bespoke and I think we have all gone for different lengths!

John, At least it is the outer cv and not the expensive inner!

Meant to ask you earlier how was the drive?? Did you give it any beans?
7 Jan 2008, 5:43pm
craig wrote:
John's Shafts as are all of the type r builders bespoke and I think we have all gone for different lengths!



I think if anything on the shaft has failed, it's the circlip for the outer - will check and report back.

craig wrote:


John, At least it is the outer cv and not the expensive inner!



Hopefully the spline hasn't been damaged.....

craig wrote:


Meant to ask you earlier how was the drive?? Did you give it any beans?


Beans - quite possibly, but this is a public forum.....

Back end feels a bit funky at times, as we know to be the case. Brakes were a bit lame initially, but then that's expected as they're so new...... but it's a laugh to drive, it makes a hell of an amusing din (especially under full chat down brick lined roads), and the pain is worth it.

I'm not too bothered about the SVA / CV - it's all part of the learning experience.

Craig, while I remember - the Elise seats are fine, but the part of the car they mount to, needs to be welded in place, and really obviously substantial. You must also use the OEM seat frame mounts, and not cut and shut them. I don't know how you've done yours, so thought I'd give you a heads up.

Edit - I just popped out to get something from the car, and levered the cv boot off whilst there....


7 Jan 2008, 6:37pm
DavidH wrote:
(refering to 2nd to last picture)
What SVA centre did you go for, it looks like you'd done some miles on the journey. Sounds like you had a relatively friendly inspector (unlike some of the tales you hear) and at least the failures dont sound too bad to correct.


Taunton. When the CV died, I'd done 140 miles (about 15 miles short of home) - I have a habit of getting lost ;)
7 Jan 2008, 7:41pm
Sorry to hear about your problems but sounds like it will not take too long to fix those SVA failures.

Well done must be a great feeling to drive your own car.

Mine is nearing the SVA test, do you know how long the waiting list was when you booked yours in ?

thanks
7 Jan 2008, 7:45pm
Waiting list for mine was pretty short - I applied in Nov' (can't remember exactly when) and I requested a January test date.

I asked about the re-test, and I was told that SVA traffic is pretty low this time of year, so I should be able to book it within a fortnight, perhaps a week.

A quick type-r specific comment - my sound test yeilded 98dB @ 5500 rpm. Standard Marlin silencer, 2.5" pipe, and 200 cell sports cat.
7 Jan 2008, 11:26pm
Pretty painless failure list John; good work. Shame about the cv joint but could be worse! Hope it's not symptomatic of a shaft being a bit short though. Or long...
Very interested by the noise measurement. As I mentioned mine never actually go checked - but it did sound a treat going around Llandow. I have to be very careful pottering round town if I don't want to look like a tw*t all the time. I have had walking sticks waved at me on country lanes too - not because I was going fast but because it *sounds* as if I'm going fast!

Anyway, good luck getting the little bits sorted and getting that precious SVA!

Richard

PS I bet the drive was a complete blast eh? Funnily I got a bit lost on mine and clocked up 120 miles or so...
7 Jan 2008, 11:32pm
Rich,

I'm suspecting it's a bad gaitor, coupled with some rather abusive right foot action that killed the CV joint. I noticed at the SVA that the OS CV had shed quite a lot of grease, but put this down to me overpacking the joint. However, the ease with which I removed the gaitor, leads me to suspect the gaitor didn't seal properly (I thought it a slightly poor fit, when I first fitted it) allowing the lube to leave the joint, and it overheated and died - the CV end of the OS shaft was very hot to the touch, yet the NS was negligibly above ambient.

I'll put another CV on, and replace all the CV ties with proper metal crimped items.

Re-test will have to wait a while, owing to too much work and no annual leave left. I've also got to fit a new screen, which is ball ache.
8 Jan 2008, 8:41am
Sorry to hear about the SVA failure mate. Not a lot wrong though. A credit to you. Different SVA examiners test thngs differently. Like your front with no mess. Mine did not have the mesh but did not get a mention.

Ah the driveshafts. I can synthesize on this ones as most turbo builders will say.

Have you got the updated rear suspension fitted? How does it feel? You mentioned feels a bit funky.
8 Jan 2008, 12:29pm
Old style rear suspension – I have the new style on order. I was going to pick it up at the Exeter show, but the factory issues have delayed this.

I’m pretty sure it’s the back end – the seat of the pants feeling was identical to that I felt in Ric H’s car, though in my case the sensation was exaggerated by the collapsible aspect of my steering column developing some rotational play during yesterday’s journey. I’ll fit another column at the weekend, and hopefully that’ll be the front end fixed.

I hope the CV failure was an isolated case, else some serious modification will be required, and it won’t be cheap. Grrr!

I don’t fancy moving the engine back too much, as the current weigh split is 43/53, with a wet kerb weight of 750kg (is that the heaviest 5exi so far???).
8 Jan 2008, 8:30pm
Interesting reading that the back end feels a bit funky, or like driving by the seat of your pants!

Im a mate of DavidH who will be attempting to help with his build no doubt... and I have owned a GTM Libra for 4 and a bit years now!

Our rear suspension has gone through a few iterations and although better still feels a bit like this on occasions.

In these light cars even changing conditions require different setup, softer in the wet etc really. I leave my car setup the same for ease of use, yet over christmas it was great on a blat on a nice sunny day, and was very "seat of your pants" on slightly damp roads a few days later. Just feels a bit skittish I guess, although Im sometimes sure its just me in a different mood and nothing to do with the car.

I even go so far as to disconnect my rear ARB in wet weather and when not on track to get a bit more feel.

But good luck getting through the SVA and enjoy the car. The 5exi looks great, cant wait to get started building one...

GarethW
8 Jan 2008, 9:38pm
It's interesting to hear about other kits with a similar layout.

I think I should clarify the sensation I felt. Basically the back end feels fine under steady state (ish) conditions, so under power, it feels fine, and under braking it feels fine..... the problem (to my mind) are the transient phases. So if you accelerate, then back off, or worse still, brake, the back end feels to squirm and does not inspire confidence. Ric H and I spoke very briefly to Mark M at Llandow, and without prompting he said the redesigned rear end was born out of the unstabled feel at the rear of the car.

Whilst I only drove 140 miles yesterday, I did encounter a variety of road conditions, and the feel of the back end was largely consistent. The most obvious variable was the throttle required to initiate wheelspin.
8 Jan 2008, 10:01pm
Good description John, and spot on in describing my car's behaviour. The problem becomes more apparent at speed. In, ahem, high speed trials on a 3 lane deserted, ahem "closed track" I found the car really very stable under power up to a speed when my nerve ran out. However, as soon as I eased off it was a different matter - the rear snaked to such an extent I needed half of each lane either side to keep it under control. A little unnerving, I'll say.

I'll be very interested to see how you get on with the new rear, John. I've been a bit preoccupied recently and haven't got around to getting mine ordered. In the meantime I've been wondering what I might be able to achieve by playing with the rear toe. I've wondered if it's the toe swinging out under deceleration (it is pretty flexy afterall) that initiates the snaking, and so am thinking of trying some significant toe-in at the rear. Not sure what other effects that will have but hey, it's all experience gained!

Richard
8 Jan 2008, 11:19pm
Ric H wrote:
... am thinking of trying some significant toe-in at the rear. Not sure what other effects that will have but hey, it's all experience gained!


What is your toe-in setting at the moment?

I'm running 0 deg, 20 minutes.
8 Jan 2008, 11:40pm
Running parallel at the rear at the minute (within the accuracy of careful string measurements!). I was thinking of toeing in 1-2mm, which a quick calc says is about what you've got? Maybe I should try more... though it's so easy to change that I might just play around for a bit.
8 Jan 2008, 11:48pm
Hopefully I'll find some time to get my car through the SVA retest (haven't got a plan at the moment - might need to buy some time off :(), by which time Marlin will hopefully have fired up production again, and I'll get my phase 2 rear suspension.

When I fit that, I'll set my rear toe the same as it is currently, and report my findings. I've got a dunlop optical gauge.

To be honest, although playing with the toe will be provide some intrigue, I don't think it'll come close enough to solving what Marlin have already admitted is an inherent flaw in the early rear suspension design.

For the record, I've got what must be phase 1.5 rear suspension, in that the upright is a reinforced item. Mark M pointed it out to me when I collected my kit, that I had Type-R specific rear uprights, strengthened to take higher loads.

I don't know what speed you "lost your nerve" at, but I had an "oooh I don't like that" experience, similar to what you described.

I can fully understand why at Llandow over the course of a lap, I was faster in my dagenham dustbin, than you were in the 5exi - one is constantly changing from loud to slow pedal, and in that situation the 5EXI with the floppy rear-end does not inspire confidence, whereas in a docile FWD car I could drive on the limit with no bother at all.

I know my comments are all based upon a lowly 140 miles of driving my 5exi, and some people may discredit my comments on that basis.
9 Jan 2008, 12:30am
Just a quick comment on SVA, I would try to get a retest sorted as soon as and ask for the same examiner that way the car will still be fresh in his mind. In my case I got my retest within a week and the same examiner - he only checked the things on the fail sheet had been rectified.