July 29, 2006

First night of 2006 for B&T Racing.  We are racing the 2001 Canaday Chassis with a ‘black’ 2003 Yamaha R6 engine converted to carburetors (we usually use electronic fuel injection).  I bought a set of alcohol carburetors from a respected engine builder.  I believe this car will sell quicker with carburetors instead of fuel injection – people still seem intimidated by computer controlled fuel delivery!

The carburetors have .116” main jets (which seems pretty large to me) and the emulsion tubes have been cut off just below the Main Jet (which also seems odd to me).  Also, about 1/3rd of each slide spring has been cut off which I don’t really like for a track like Sweet Springs which slicks off for the feature.  I don’t agree with the carb modifications, but I figured I would try them 'as is' for the first night.

Hot Laps: 

The car ran extremely well.  The chassis is neutral and required very little steering input (it was on a RAIL) and the engine ran strong at wide open throttle.  I ran four laps without cracking the throttle.

Changes before the Heat:

The track is slicking off so we tighten the car by dropping the RR air pressure to 6 psi and move the wing back about two inches.

Heat Race: (started on pole and finished first) 

Car accelerated well and I led into turn one.  I immediately went to the cushion and ran all ten laps at or near wide open throttle (never backed off more than 50% throttle).  Engine ran well, but with the stock 15,000 rpm rev limiter we were hitting the limiter just past the flagstand.  The car is a little loose, but pretty darn good.

Changes before the Dash: 

Track continues to get slicker – tightened the car by adding wing angle.

Trophy Dash: (started third, finished third) 

LOOSE!!!! and engine did not perform well at part throttle.  I cannot tell if the engine is rich or lean because my data logger (Oxygen sensor) is not working properly. 

Changes before Feature: 

I don’t have any other carburetor jets, so we decide to run the engine ‘as is’.

Tightened the car with 5psi in RR tire and moved wing back.

Feature: (started 17^th, finished 11^th) 

The engine is horrible at part throttle and this messes up the handling of the car.  The engine lugs off the corner then comes on hard at mid straight so my timing is off and I drive too deep into the corners.  By lap eight I crack the top ten, but then I run out of talent and hook my front bumper on Knipmeyer’s rear bumper and spin myself in turn one.  Back to 17th place.  The engine is even worse (after I flooded it trying to restart after my spin!).  We fight for a disappointing 11th place finish.

Wrap-up:

We have a lot of work to do to get this thing FAST! 

I will completely rehab the carburetors to my liking and try again August 19th.  I now remember why I dislike carburetors and prefer electronic fuel injection!