Nope - but just one item left

Back to Gillingham this afternoon for the re-test;

Emissions - Fail - Again!

I thought I would be ok on emissions - first time round she was fine at high revs but too rich at idle & I had practice at tweaking idle now - managed to get the CO down to 0.2/0.07 stored in the map -  but then high revs was too lean & you need 3 hands to adjust the map in the right place while holding the revs at 2.5k.

I had 2-3 goes but it just wasn't happening so we moved on to the other items;

Everything else checked out:

• Noise down to 92dBA

• Wobbly mirrors cured

• Exterior projections fine with my silencer guard

• The steering rack boots are still within a gnat's of the lower wishbone mounts and the tester thinks they might need adjusting for each MOT - but passed none the less.

• The rear brakes a little uneven balance and the nearside could probably do with another bleed - but again - a pass.

A few pictures of the Zero & Me on the ramps at the testing station:

Overall another fail - just emissions to go - I think its time to invest in an all up dyno - I've had two tries at getting the mixture right & for whatever reason its beyond me.

Consolation

The consolation was a drive home in the car - the sun even came out for me & a total of 67 miles on the clock now.

Excellent to drive - even in moderate traffic through Maidstone, new eye sized windscreen/goggles do the trick I could actually see where I was going today:

Net result

Splashed wife - for some reason the passenger gets much wetter than the driver from road water ;) but she did enjoy the ride out.

Trouble with insurance (too long on the chassis number) so will have to cross that bridge too.

Need to organise a Dyno, seems like BD Engineering aren't around for a couple of weeks, need to do some research - The ideal would be a garage which could setup the engine & accompany the car through the IVA too (Like the GBS IVA service - but closer to home & only on the one emissions point)

We're getting close, very close...

Re-test day

This is going to be interesting.

IVA re-test @ 3pm, and currently the weather in Kent is raining and not forecast much better for later - perhaps I should spend this morning making some wipers for my goggles  :)

Re seat the plenum

This evenings work consisted a short call to Simon @ GBS for advice, consulting Paul94's blog and re fitting the plenum & injector adaptor.

Current advice is to seal the plenum to the adaptor either with glue, grease or in my case my instant  gasket. Ensure the rubber 'o' rings which sit against the head & the injector 'o' rings have a smear of grease and assemble to avoid any air leaks:

Loctite 5922 instant gasket, the same stuff I used on the sump seal; This stuff isn't meant to ever completely dry but will allow me to dismantle again later if I need to:

This certainly made a difference, after re-installing everything the engine wouldn't tickover and needed more air through the IACV - a good sign - it must have been pulling in air from leaks previously.

I spent a while in the drive re-working the IACV table on the ECU; things seem much more stable now - i.e. predictable changes when the injection or air is changed. Hopefully this will help - I should just have time this week for another test at the local garage before IVA.

Emissions testing - air leak

I took the Zero into a local garage, H&C Motors Maidstone, to check emissions & brakes. They were really helpful spending time helping me identify problems.

I'm happier now about tweaking the emissions while the car is on the machine; however while I can get the CO levels under control by changing the injection my Lambda & O2 remain high - the garage thinks I have an air leak on the inlet side somewhere so I need to re-visit the plenum & injector seating.

We also ran the brakes through a test, foot brake is fine now on the rears but the handbrake is still weak.

That should keep my evenings busy this week - I'll strip down and re-fit the Plenum, injectors and intake adaptor & take a look at the brake leverage. With hindsight I could have done all this testing before I went for the original IVA ah well...


Another outing in the Zero though; just 5 minutes down the road this time though into Maidstone.

Noise - testing the sound levels

Al Milton kindly offered to come round and help test the noise levels, he had access to a noise level meter.

After a couple of runs today with Al's help it looks like I'm anywhere between 92dBA and 99dBA - depending on the revs; So the wire wool in the silencer is definitely doing its job.  Thank you Al for giving up your Sunday morning!

David S kindly shared the outputs from his recent Dyno run - David has an identical engine, intake, exhaust & silencer setup to me. David's Zero was producing 163bhp @ 6,067rpm before tuning & 168bhp @ 6,182rpm after.

I'm hoping I can use this information to persuade IVA I put the wrong values on the application form (165bhp @ 6,500rpm advised by GBS). I already discussed changing the rpm on the form & they will do so provided I can come up with some evidence. If I can get a lower max power RPM on the form the noise text will also be run at a lower rev range (0.75 x max power RPM) & get me a little breathing room on the noise levels.

Good support from my fellow RHOCaR club members -  Thank you!

Re-assembly

I'm back in countdown to IVA mode;

Today

Painted the inside of the wheel arches with under-seal to give a little more protection than just GRP - it also looks more solid;

Removed the spare carrier assembly and re-inserted grommets;

Wheels back on with locking wheel nuts;

Re-installed the nose.

Next up

A RHOCar member is going to help out with a sound meter next weekend & hopefully another has some evidence that 2.0 Zetec's with the GBS plenum generate max power around 6,200 rpm - both of which should help me get through the sound issue.

Emissions is still a question - I'm more confident now about changing the mixture on the fly - but if I can sort something out it would be great to check the absolute emissions level before the retest.

I need to make time to contact a local garage for the emissions and brakes check...

Boot carpet

I bought the full laser cut carpet set for the car and the final part to be installed is the  rear panel/boot space. Nothing of particular note really - the flap in the centre back is to gain access to the spare tyre bolts and under the rear edge I have glued my custom boot floor to stop anything falling down behind the fuel tank and on to the road:

The bottom carpet is held in place by gravity only, so I can lift it and get at the differential access panel and top of the fuel tank at any time:

ECU - Auto advance: off, Lambda: open loop

Engine runs fine; but I need practice on tweaking the injection while the test is going on.

I went back to the stock GBS Emissions map today and applied minimal changes - only changing the injection corrections table to enable easy starting - by default the engine gets extra juice for 5 turns - upping this to 50 turns and increasing the initial injection produces a first time start every time.

I went through the IACV mapping again and then just tweaked the injection (keys 2-3) during tickover while watching my narrowband Lambda output. 

I had turned on the automatic advance in idle control, this seemed to fight with the lambda sensor when it was set on closed loop; indeed the lambda sensor seemed also to react too slowly and cause an uneven tick-over - only self adjusting the injection every second or so & then to its extreme +-10%. After a lot of trying different lambda options I decided to leave it on open loop and disable the automatic advance too.

Status:

I know I can achieve a stable tick-over at varying injection adjustments, 

I know this adjustment takes me either side of 14.7Lambda using my narrowband, 

but still no way to actually measure the output and check it is within regulation - I need to either find a local garage or run it at the IVA station!

Updated the ECU page with findings.

Spare wheel carrier #2

Its starting to get warm enough to work, but raining today so I decided to do a little construction.

My GT Chassis has a factory modification to allow fitting a spare wheel carrier, it needs fully fitting out including the wheel retaining bolts which in turn will allow me to finish carpeting the boot interior.

First up the bolts which retain the 'U' bar - these just needed cutting to length and a little fettling to get the U bar protruding the right depth for my tyre:

The U bar takes the tyre weight, then I decided on two threaded bars through the boot panel to steady and retain it. Behind the panel another plate of stainless bonded in place strengthens things and spreads the load:

My two threaded rods. I couldn't find M12x1.5 rod (the same as the wheel bolts) but did find M12x1.25 & some matching nylocs & locking wheel nuts:

Hindsight - I ended up fitting double nuts either side of the panel. This means they lock against each other and I can choose which one undoes - rather than the loosest one.

The threaded bars bolted in place with nylocs either side of the rear panel, on the inside this will be covered by carpet - leaving the bolts exposed so its possible to remove the wheel:

Then the wheel slips over them:

Hindsight - These nuts are doubled up now & a washer

Of course - this all has to come off for the IVA retest, the threaded rods will need some paint too to prevent a nice rust effect & a number plate bracket & light arrangement. 

Still - at least building things is a more positive experience than doing nothing waiting for the weather to clear!

Round two - IVA

IVA re-test booked for 26th April.

This month has been trouble, poor weather preventing me get much done on the last re-test item - emissions and the ECU setup.

The insurance company are being reasonable, but I've been a while now on a chassis only policy and they are getting twitchy about the lack of registration...

Hopefully the weather cheers up and gives me a chance for a good session on the ECU to try and sort out the low rpm tickover mixture. First time through I was ok on the high revs but couldn't stabilise the mixture at low range tickover.

UK Easter - too cold

No progress this week;

The weather has been awful in Kent - not a glimpse of a warm morning to get the car in the drive and mess with the engine & I can't run her inside the garage due to fumes/noise.

It looks like brightening up this weekend; unfortunately I'm working and won't be able to make progress.

Really just needs some tweaking on the ECU Map and I can book her back in for the IVA retest.

Silencing the silencer

A little real work; longer days are back with the clocks changing but its still pretty cold in the garage;

I took another look at the silencer & the wire wool down the pipe approach - my first prototype was promising but needed some way to secure it - concept demonstrated in this picture - a wire from the bottom of the can out through the tailpipe which could be secured to the wire wool cage. The challenge was not knowing the internal design of the GBS silencer & knowing there would be a central holed pipe to negotiate:

I drilled through the centre of an existing rivet and managed to feed a short length of steel cable through the hole, through the central silencer pipe and out through the tailpipe.

Test run with my prototype caged wire-wool extended - excellent blueing of the wool after some engine runs, but overall this was just too complex - time for a little simplification:

I decided on a much smaller cage which would simply stop the wool being pushed out - internally the wool bundle is held in the central silencer pipe anyway. This little 2" long cage grabs the end of a 12" long wire wool bundle and follows it into the pipe secured in place with the wire through the bottom drilled out rivet hole:

Cable secured underneath with a self tapping screw:

Just the tip of the wire wool visible in the tailpipe, hopefully its far enough back to let the IVA emissions probe insertion - checking with them they need 3" for the emissions probe so I should be fine:

Finally tidied up with the cover back in place - I also added a strengthening bracket with 2 rivets at its mounting point:

Update - This didn't really work at all - quietened the exhaust ok, but means the emissions are impossible to test because the emissions probe will no longer fit in the exhaust. Ultimately passing the sound part of the IVA was down to making sure the car wasn't near any buildings so no sound reflections.

Go faster stripes... Nitrous & Santa Pod

The GBS plenum has a take off at the rear - currently mine is connected to the fuel pressure regulator via a vacuum feed - however, bored with all these IVA tidy ups I was thinking of something a little more interesting to attach here & enhance the performance...

SB150i Nirtous Kit wet setup should be easy enough to plumb in, there's plenty of room on the scuttle/battery tray area for the equipment:

Reading through the various FAQs on the subject & Install guide it doesnt seem to difficult, and luckily there just isn't a section in the IVA regulations regarding this type of system so it would appear to be completely road legal.

The car weighed in at 803kg (laden weight) at the test, so a little N2O injection should help the 0-60 numbers & the ideal place to test will be the Run What Ya Brung event at Santa Pod in May.

I think I'll be ok provided I tick the standard loof-lirpa box on the IVA and insurance forms.