BRANDS indy , October 2005

update: engine was spluttering all over the place and its not the quickest lap on skinny road tyres but i took a few moments out to add some logging data to the movie below

A quick check on the car before my trip to spa at an evoactive day at local track Brands.
First time out and its obvious that Steve Greenalds recent mapping has sharpened the car up. Throttle response feels noticeably crisper and the engine revs more freely.

The misfire/splutter (which now cannot be driven through) first seen at Snetterton is sadly even more apparent in the upper ranges. I disconnect the battery cut off and my starter switch but to no avail.

What we do know is that this anomaly not only has nothing to do with the mapping but it does not occur on the rolling road so it really must be something to do with mid to low frequency mechanical vibration and cornering load.

A quick look at the datalogs indicates that it could well be the crank sensor again which would make sense chronologically because it proabably got hit/scraped when I went into the gravel at the end of the day at Oulton, i.e. when the misfire started again. The datalogging trace for rpm dips very suddenly when the splutter occurs, arguably too fast than an engine can actually perform given its inertia characteristics... over 1000rpm in a split second. Given that the rpm for the logger is the same as what the crank sensor reads, there is a good chance that the problem lies in that area.

Very tired and not driving very well at all especially after lunch, i just get slower and slower and start making mistakes. There are a number of stoppages, a 355 almost totals itself, a yellow elise smashes the tyre wall after surtees and after one session trying my slicks I make an early exit and use a couple of red bulls just to get me home.

 

 

MOVIES

Seat Cupra cup car
Windows Media WMV 10mb

me on 6" A032's, the 250bhp cupra race car on slicks, trailbraking nicely into each corner

NOW WITH LOGGING

split screen
Windows Media WMV
6mb

just a dual view, gives you an idea just how close cars are in front even though in the bullet cams they look really far away

 

 


The Jackals Racetrack http://www.jackals-forge.com/lotus 1998 Richard Morris