Saturday, 19 October 2013

Happy Birthday

This week saw the 1st anniversary of the car being registered, after a week of rain the forecast for the morning was clear with rain starting around mid-day.  Unfortunately this was wrong and I got soaked dropping Allanah of to dancing!  With the rest of the day forecast as rain showers I decided to fit the shift light.  After isolating the battery James drilled the 14mm hole for the LED under the T lights on the dash and installed it.  With the dash removed I dropped the ECU panel and loosened all the looms so that I could access the back of the main OMEX600 connector.  The shift light is pin B8 and it works by providing the earth through the ECU.  Unfortunately the B8 only had a seal fitted and the kit didn't include the connector pin so I had to down tools.  Myles wanted to investigate the noise from the pedal box so we removed the cover and he operated the pedals while I looked and listen,  there was no obvious problem but the noise of the clutch pedal hitting the end stop seem to replicate the noise so hopefully nothing to worry about.

In order to prepare for the next rolling road session at NMS I've ordered a set of 10mm racing HT leads and NGK Iridium spark plugs.  The supplier Formula Power were recommended by an Aston Martin owning colleague as he'd heard about them through his owners club.  Not much cheaper than the well known Magnecor 8.5mm so they better be good! - also available in blue rather than the Magnecors that  are only available in red.  I also saw that another WSCC member, Darve, who has just successfully IVA'd his MX5 SDV had completed some head work, change his cams and them got NMS to map his car and achieved an additional 25 bhp, perhaps something for next winter.  The WSCC Forum posts went on to discuss fuel for RR sessions.  When I can I use Tesco's Momentum which is 99 octane rather than the normal 95 but the WSCC Forum recommendation was Shell V-power, last time I was at NMS I filled up at the Total (I think) garage on Towcester Rd just round the corner from them.  Logic tells me that you should use what ever you normally fill the car with for a RR if you want to get a realistic result.

I exchanged emails with Paul and Joe Bromley during the week and they've decided to sell their Westfield due to a combination of: limited suitable roads on the IoM, lack of WSCC social side, lack of time all resulting in only 500 miles driven in the first year of ownership - car is now on ebay an awesome car offered for sale a substantially less than build price, someone will get a bargain; there's a link on the RHS of my blog to their build blog if more evidence is required.

Saturday, 12 October 2013

Front ARB Brace

Whilst at Northampton Motorsports Chris told me that Westfield had designed a chassis brace to link between the two ARB bell cranks to address an issue with chassis cracking due to the stiffness of the ARB. I phoned Westfield when I got home and they had them in stock.  £31 later the brace arrived in the post the next day - excellent service. 
Brace in place

After dropping Allanah off for dance the weather was miserable so Myles and I went to the garage to fit the brace.  Luckily it looked like the bell cranks would unbolt without having to disconnect the ARB.  After the bell cranks had been unbolted from the upper wishbone and the brace had been fettled a little, everything was bolted back together, minus a washer, and the job was done.

Myles torqueing up the upper wishbone bolt

I'd spoken to Troy at NMS during the week about the cam swing and the car is now booked back in for the end of the month for it to be done and the engine remapped.  Even with the Cat in the exhaust I'm hoping for another 5 bhp with no loss of torque.

I've been monitoring the ongoing debate on the WSCC forum with regards cooling.  On track days I've been limiting myself to about 8-9 laps; 1st lap to warm everything up and last to cool everything down and once on the flying laps the coolant temperature rises to >100 deg C.  The original debate was around ducting but now is on the capability of the radiator and merit of the Radtec Alloy Radiator - possible next upgrade?

Friday, 4 October 2013

Northampton Motorsports - Rolling Road and Geo Setup

The weather forecast wasn't looking too good, so I put the 1/2 hood on and set off for Northampton at 05:30.  Just after passing Thruxton I stopped for fuel at Buck Services on the A303 then headed up the A34, on to the M40 for a couple of miles before turning off onto the A43 and the final 30 miles or so to Northampton, going past Silverstone and the back of our old house at Towcester.  I arrived at NMS at just after 08:00 and then went and refilled with fuel at the garage just down the road.

The first job was Corner Weighting and my first decision to make was 1) driver only or 2) driver and passenger?  After a brief discussion on the pros and cons I decided to do driver only on the basis that Corner Weighting was over kill for a road car so mainly for track days, so better to accept any compromise on the road.  Chris disconnect the front ARB, checked the tyre pressures and each of the wheels - n/s rear had play in the wishbone bushes which he tightened (need to watch them) then onto the scales - car, full tank of fuel and me - 725 kgs ouch! 

At the IVA they recorded 675 kgs which included a 75kgs allowance for the driver and perhaps only 3/4 of a tank of fuel (last minute leak and dodgy gauge) so the inboard ARB is heavy! The car was reasonably well balance already and Chris made the final adjustments to the rear shock absorbers and confirmed the ride height was 35 mm nose down which was in the middle of the 25 - 45mm range that he recommended for a fast road/track set up.

Next came the Tracking and again nothing drastically wrong especially given that the ballasting for the driver first time was  a tad underestimated and I'd swapped out the steering rack a couple of weeks ago using tape on the garage floor to transfer the distance between the track rod ends.  Second decision was to keep with the fast road/track day setup so slightly more camber on the front and not so much toe-in. 


The final thing was reconnecting the front ARB, this took a reasonable amount of time as Chris wanted to ensure that it had free movement throughout the full wishbone articulation to minimise the chassis issues that have been experienced by some. 

His final advice was to fit the cross chassis brace that Westfield now make to help with the chassis issues and a rear ARB to complement the front - the brace was in stock at WF so now ordered at a cost ~£27+P&P.

After a very lightweight - diet started already - lunch the car was strapped to the rolling road, lambda sensor replaced with the rolling road one and Troy started to work his magic.  First was a check of the throttle and the pedal stop needed adjusting to allow a full WOT to be achieved.  Then the TB balance and he was happy that, after my numerous attempts, they were balanced.  Once the oil and coolant had been checked, Troy confirmed I was happy to use the full engine rev range and then he was off.

After a run with the original map he saved it and loaded his own base line map.  The first few runs established the full throttle performance and after some adjustment of both the fuel and ignition maps the power runs were completed 166.7 bhp @ 6,700 rpm and 143 ftlb @ 5,400 rpm.  Slightly lower bhp than I'd hoped for but the torque was smooth and above 125 ftlb from 2,700 to 7,000 which should make for very driveable.

Troy then moved on to the full mapping adjusting both the fuel and ignition maps plus a whole series of other adjustments.  Once he'd done the individuals stop points he then used the 3D graphs to make final adjustments - the speed at which this was done and attention to detail was amazing to watch.  After some final test runs Troy declared that he was happy and the final map was saved and the ECU updated.

It was now 14:30 and I discovered that it was now raining.  After paying the bill and getting some stickers for the car I head off in the rain back to Yeovil.

I immediately spotted that the speedo wasn't working a remembered that Chris had found and fixed some play in the o/s steering arm so I pulled into a layby on the A43, quickly adjusted the sensor and  re-tightened up the caphead screw then got back on the road.  By now the rain had stopped but the roads were still greasy so I took it very easy.  My initial impressions on the mapping were wow - the car was so torquey and smooth.  The flat spots in the low to mid rev ranges were non-existent and the engine even seemed to rev much more quickly.  On the ride the benefits weren't so clear but as the journey progressed the roads began to dry out and I began to push a little harder (although never above the speed limit, honestly officer) by the time I got to Yeovil I was convinced that I could feel the difference and it was that the ride somehow smoother and the steering more precise.

After a bite to eat at home I headed off to the WSCC meeting just outside Dorchester armed with my pack of printouts and had a very enjoyable evening comparing notes on the visit to NMS and enduring the banter "only 166 bhp on TBs got more from my 1800 on Webbers" etc etc - on the drive home I was now convinced that the car was transformed - but I was now very tired and needed my bed!