Monday, 16 May 2016

Engine Calibration development ongoing...

Getting there, still some work to do before final mapping but I'm hopeful I'll be able to drive it up and down my driveway shortly..

Saturday, 19 March 2016

Clutch & Flywheel

Apologies for the time since the last post. I'm making up for it though with my longest post to date. 


So another area I'd identified for improvement on the car is the clutch and flywheel.

As standard the F355 ran a dual mass flywheel, probably one of the earlier applications on a high performance car. The two elements inside the DMF are torsionally damped by some sprung elements, but also by a special Kluber grease. The cars are notorious for problems when the grease has either liquified from a gearbox oil leak from the 'triple seal' on the transfer shaft, or solidified through absorption of dust and other debris.

In order to avoid these issues on my 2nd hand 'box (and because I spotted room for a very significant weight saving) I decided to switch to a traditional single mass, lightened flywheel, with a sprung-centre paddle clutch (the standard F355 friction plate is not sprung as it is assumed the DMF does all the torsional damping).

I also swapped out the F355 solid transfer shaft for one from the Ferrari 348 which is gundrilled from both ends and 30% lighter.

The flywheel and clutch were provided (with great service) by MD Clutches (link on my links page). The flywheel is completely custom and nearly 50% lighter. The sprung clutch is adapted from a Ferrari 360 unit.

The pressure plate and all the clutch release gubbins are carried over, and I swapped in some Ti bolts for added intertia savings on the pressure plate.

The total weight savings look like this:

Old (g) New (g) saving (g) %
friction plate 1163 1919 -756 165.0%
M6 bolts 88 45 43 51.1%
shaft 1828 1292 536 70.7%
flywheel 10700 5726 4974 53.5%
pressure plate 4658 4658 0 100.0%
18437 13640 4797 73.98%

I also put some work into the clutch cover. I'm becoming pretty blasé to taking an angle grinder to Ferrari components now, which I'm not sure is a good thing!

Anyway another 250g saved and I'm very pleased with how it came out. :-)

Overall 5050 grams saved. 4800 of them rotating mass, and all of them hung out behind the rear axle!

Sunday, 7 February 2016

Software & setup - Part II

So continued I playing with the software until after a couple of days I got this:

Very quickly followed by this:

(apologies it's so dark, I just moves to a new house and while the garage is bigger it is very poorly lit at the moment. 4 big striplights are an urgent necessity!)

While the engine is running you can view all channels and parameters live in CalTool. Getting a nice healthy 6.8bar of oil pressure at cold idle.

Dropping to around 3.2bar at hot idle.

Next jobs are to iron out a few niggles with the control of fuelpump and waterpump, do an oil flush and filter change, then I can begin refining and mapping the base calibration. 

Sunday, 31 January 2016

Software setup - Part I

Now we are onto the engine software and hardware set-up bit. Sensor calibrations, strategy writing and ultimately engine firing for the first time hopefully. 

The software we are using is CalTool from Pi (Cosworth).

There are literally thousands and thousands of functions, 90% are not needed for my application.  Here's just a few screengrabs to give you an idea of what we are working with at the moment...

We have sucessfully tested the PWM fuel pump control. Here's an overview of the parameters!!

Monday, 11 January 2016

Chassis, Dash & Comms - Part II

So following on from the last post, here's pics of all the loom forward of the bulkhead fitted to the car. 

It all went together exactly as planned which is nice.

 Main bulkhead connector from rear.

Bulkhead connector, ECU, starter and fuel pump driver module relays mounted to front of bulkhead.

Dash area starting to look neater now..

Powering up for the first time:

Friday, 8 January 2016

Chassis, Dash & Comms loom - Part I

Will be spending all weekend fitting the chassis loom, relays and ECU to the cockpit. the ECU and three relays pictured in the first image below will live on the inside of the bulkhead.

The other 3 relays will live in the space under the standard S1 dash top, which is rather cavernous. 

Sub-loom for Omega Digital Dash (means that future upgrade/change of dash type is more straightforward)

Friday, 1 January 2016

New Year's day updates!

Happy New Year everyone. I'm looking forward to 2016 as the year to finally get the car finished and go out and enjoy using it! :-)

I've had a very productive couple of weeks on the car, in no particular order:

  • Engine loom installed. Hole drilled for bulkhead connector to chassis/cockpit side loom.
  • Brakes bled. Initially we had a slightly spongy pedal but tracked this down to some slight play in the hydraulic handbrake mech. Once I rectified this the pedal feels great. I am hopeful the brake performance and bias will be pretty good out of the box.
  • Clutch bled. Got lucky with this one and the matching of standard S1 lotus master cylinder to standard Ferrari slave cylinder has turned out to give an almost perfect pedal feel and weight. The clutch seems to engage and disengage smoothly. I believe the plates have only 17,000 miles on so hopefully there is a goo bit of life left in it yet.
  • Rear wing endplates made. I had been holding off on this as I couldn't decide what to make these out of. In the end I plumped for the same ABS-based material I've used for the side skirts. The only downside of this material is I can't quite figure out how I'm going to create the louvres we want. More thinking required..!! (but they will do for now!). The geometry of the endplates has been suggested by a friend of mine who is an aerodynamicist for Williams F1 team.
  • Diffuser consctuction. Started out by extending the standard S1 elise diffuser and using that as template. Will do a full post on the diffuser once it's complete...