The cars engines have to use a 74 mm restrictor i believe so most teams use a machined piece thats hourglass shaped to accomplish this.

 

The restrictor diameter is 20mm for gasoline cars and 19mm for E85 cars. The "hourglass shape" is a converging diverging nozzle, the most efficient design for an orifice.

 

Ourbaja car just started rolling this week.

 

lmao

i like how csu copied their front suspension almost to the T out of a Sports 2000 race car.

 

Yeah 74 mm i don't know what i was smoking when i said that lol. Doesn't the restrictor size change if the car is forced induction.

 

I was there for my second year and it was fun again. My good buddy goes to Wisconsin and his team won the 2007 FSAE.

 

i dont know if the size changes, but I do know that not alot of the cars have forced induction because they have a problem with the flow in the nozzle going supersonic and shockwaves in the intake = FTL

 

The restrictor size doesn't change for N/A or F/I engines. It limits the maximum amount of air available for the engine to breathe, thus limiting potential power. Many teams are choking their restrictors with their N/A engines, especially the ones with poor restrictor designs. All engine's are limited in size to 610cc.

You might think that an F/I car would have an advantage but thats not always the case. VT put down 74 at the wheels, higher than most of the turbo cars, but not the highest overall. The big advantage to running a turbo (Garrett has two turbo options, the GT12 and GT15, both of which fit in the palm of your hand...) is that the turbo enables you to max out the restrictor sooner than an N/A engine normally would. While both engines might make the same max power, the turbo motor will reach that power earlier and just hold it to redline instead of a gradual power cresendo.

 

Choked flow = no good. Also, many restrictors are just poorly designed, period. I threw this together the other day just to get a feel for what's going on inside one of these things. This would be a "bad design". Turbulence intensity is shown:

 

<---- Former Aurburn University Formula SAE and Baja Team member.

Nice job, great pics, impressive. I miss those days