December 13, 2004

Rolling road shootout!

Chris Rome and myself went along to Surrey Rolling Road at the weekend to try our cars back to back on the rollers. My car has always appeared 'faster' than others down the straights and so the expectation was that my car would show power at the upper end of the Rover claims.

I know very little about rolling road accuracy or otherwise, but the cars were strapped down onto the rollers. Although I wasn't paying particular attention, there seemed to be very little movement when the power runs on my car were being done. The at the flywheel graph is below.

Now the headline figure (115 bhp) looks fine although the power dies away more sharply than I'd expect above 6K. There is a large dip in the torque curve lower down as well.

So, Chris' car was put on the rollers and during the power runs the back end seemed to be moving a lot more, implying that it was wasn't as 'tied down' as mine. Anyway, the headline figure is 120 bhp and a slightly unusual looking set of curves given the Rover claims. Here's the two traces overlaid (my car - red, Chris' - blue):

As a point of reference - Caterham quote a max power of 115 bhp @ 6K and max torque of 107 lb/ft @ 3K. My car showed 115 bhp @ 6K and 112 lb/ft at 5K rpm (!) [and around 107 lb/ft at 3K rpm]. Chris' showed 122 bhp @ 6.6K through to the redline and 108 lb/ft at 3K rpm [with only 105 lb/ft at 5K rpm when my car was showing peak].

Interesting that I seem to have a sudden torque surge at about 5K rpm. Basically, the comparison seems 'wrong' due to some factor (such as the way the cars were strapped down). I'll also be doing a compression test now to narrow down whether I've suffered from the curse of the cracked number 3 piston.....

Posted by charles at 1:40 PM

December 20, 2004

Engine checks

Chris and I did a compression test on our engines over the weekend - both showed no problems when warm (and we didn't test when cold) so all is looking good. They'll get a better check (leak down) when the steel valve spring caps are fitted by Caterham.

My battery is suffering with the dual factors of not being run and the cold weather, so I've ordered an Optimate III battery conditioner from M&P Motorcycles.

Posted by charles at 7:55 PM

New tow car...

Forgot to mention that I've treated myself to a new SEAT Leon TDi 150 FR! I know that you'll all miss the Nissan and its lovely beige interior but needs must. I still need to fit the tow bar before the race on Boxing Day though so it's going to be very tight!

Posted by charles at 8:01 PM | Comments (2)

Guy said:

Can't believe the old girl is gone. Doesn't seem like yesterday that you brought her over to show off her new trailer!

Do Seat do beige?

All the best - good luck for tomorrow


Mad Max said:

Nice choice matey. You won't go wrong towing with a diesel.
Anyway, where's the footage of Mallory then?
Come on. I want to see Patrick going off into the barrier!

Keep up the good work Charlie boy.