Still in Balance, No offence taken
Hi Doug,Keith,
You have to remember that F1/ Indy car motors are short stroke/small capacity motors, and the weights of the components are considerably less than we are dealing with in our average SB Ford etc. On the Flat Plane/180deg crank you have two pistons @ TDC on the same bank @ the same time while the conventional 90deg has one on each bank.
With regard to the Balance the Flat crank will always have a secondary imbalance that shows up around 2/4000rpm from memory, If the motor is operated at this RPM for a constant period the vibration will cause problems.( Have you ever watched a F1 team when they first start up, they dont run them @ constant rpm at all.) Since the F1/Indy motors dont spend much if any time at that rpm its not a problem, but you would not like to drive in downtown traffic for long. The other benefit of course is weight reduction, The crank does not require the same large counterweights @ each end, and since each bank has even 180deg firing the exhaust system is a simple 4/1 on each side which also allows the car to have a smaller profile etc.
Smokey Yunick wrote an excellent article in Circle Track years ago, (I will try & dig out the issue date if you want to dig further into this)Keith , someone emailed me a video recently of the Renault F1 team going thru the warmup sequence after which they played "God Save The Queen " via the exhaust noise, that should make you happy, being a French team etc.
Cheers Jac Mac
Hi Doug,Keith,
You have to remember that F1/ Indy car motors are short stroke/small capacity motors, and the weights of the components are considerably less than we are dealing with in our average SB Ford etc. On the Flat Plane/180deg crank you have two pistons @ TDC on the same bank @ the same time while the conventional 90deg has one on each bank.
With regard to the Balance the Flat crank will always have a secondary imbalance that shows up around 2/4000rpm from memory, If the motor is operated at this RPM for a constant period the vibration will cause problems.( Have you ever watched a F1 team when they first start up, they dont run them @ constant rpm at all.) Since the F1/Indy motors dont spend much if any time at that rpm its not a problem, but you would not like to drive in downtown traffic for long. The other benefit of course is weight reduction, The crank does not require the same large counterweights @ each end, and since each bank has even 180deg firing the exhaust system is a simple 4/1 on each side which also allows the car to have a smaller profile etc.
Smokey Yunick wrote an excellent article in Circle Track years ago, (I will try & dig out the issue date if you want to dig further into this)Keith , someone emailed me a video recently of the Renault F1 team going thru the warmup sequence after which they played "God Save The Queen " via the exhaust noise, that should make you happy, being a French team etc.
Cheers Jac Mac
