archetype - 17 October 2009 04:28 PM

Gurney - 17 October 2009 11:18 AM

It is possible to start a stalled car without using a starter motor.

Briefly, when the engine stops one of the pistons is at or near TDC on the compression stroke. The sensors and other gadgetry figure out which one, close the valves on that cylinder, open the valves on the other cylinders, and send a spark to that cylinder. That should be enough to get the ball rolling. The electronic wizardry then messes with the valves and sparks on the other cylinders until the engine is running on its own.

Very high-tech. Very complex. But it should work.

Seems plausible, surely it would require more than just one cylinder firing, but maybe some of the tech experts here could address this further.

It might be possible but it might also run into the engine regulation forbidding the use of anything like variable valve timing and variable valve lift systems.

US_F1_Fan - 17 October 2009 02:56 PM

Guys, nobody read my post. I am well aware of all of your comments but you ignored the fact that KERS is an electric motor connected to the driveline and if the design was tweaked it could be the starter motor.

This is true but it would also be like saying the alternator in your car could be used as it's starter. The electrical design and demands for each are 2 totally different worlds.
The KERS electrics appear to be optimized to work at the higher end of the engine's rpm range where the relationship between volts and amps is different from that required by an electric motor to start from 0 rpm with a load attached. Watch the lights the next time somebody starts a table-saw motor. They first dim as a lot of current but not so many volts are used to get the blade moving and then brighten as it gets up to speed. Inside that motor are both a starting winding and a running winding. KERS motors would have to be designed to handle both of these needs along with the electrical equipment, software, cabling etc to run it. Result, more weight. If you watched the video you should have an idea of the force necessary to turn over the engine. The article mentioned that an additional brace was used to keep the electric motor from spinning along with the operator. KERS is built on the opposite end of the spectrum electrically where the twisting forces are reduced and this means the pieces are just not as beefy as needed when it comes to starting the engine from 0 rpm.
At present time the FIA mandates that when the engine shuts down for the safety of track workers and pit workers that KERS is disarmed and discharged.

this has been talked about in another post

Heathen - 17 October 2009 06:39 PM

this has been talked about in another post

It's not easy finding an oasis of redundancy in the middle of a desert of originality.

Even though the valves are closed & piston is at tdc, you wouldnt move piston or crank very far using above method because you have no cylinder pressure to cause a large explosion in the cylinder. This has happened to me many times installing high-perf engines in cars and race cars. I check for spark on new engine/chassis combos by removing distributor from engine with all wiring attached then turn on ignition and spin distributor to check for spark.

Couldn't KERS be modified to act as a starter. Just get the Driveshaft turning and everything else will turn.

hellaciouss_craw - 21 October 2009 01:35 AM

Couldn't KERS be modified to act as a starter. Just get the Driveshaft turning and everything else will turn.

I suppose it's possible, but you'd quickly run the KERS battery flat. Remember, that thing is only good for about fifteen seconds per lap of electrical boost. Using it to start a high performance engine may drain it even more quickly. In that case, you're back to jumper cables. And if your car doesn't have KERS, you're completely out of luck, which means you have to use the plug-in starter motor.

GreyWolf74 - 21 October 2009 08:39 AM

hellaciouss_craw - 21 October 2009 01:35 AM

Couldn't KERS be modified to act as a starter. Just get the Driveshaft turning and everything else will turn.

I see your point, i was thinking of using it for a stalled car on track. Would rather not have KERS for a lap or two than have to tow it back to garage.
I suppose it's possible, but you'd quickly run the KERS battery flat. Remember, that thing is only good for about fifteen seconds per lap of electrical boost. Using it to start a high performance engine may drain it even more quickly. In that case, you're back to jumper cables. And if your car doesn't have KERS, you're completely out of luck, which means you have to use the plug-in starter motor.

Pictures are of the starter system on a 1961 Ferrari 156 Sharknose recreation that recently ran at the Goodwood revival. The car is a recreation because Enzo Ferrari had all the originals destroyed after their last race.

The first view is of the clutch pack mounted to the rear of the transmission and just above you can see 2 boltholes where the starter would be mounted but unfortunately it had given trouble and been removed. The method used was the external starter engaged through the clutch by the spring loaded mechanism. I don't know if this was on the car in 1961 but it makes sense if you want to use the starter and battery as little as possible before the race.
The car is yellow because it was recreated to represent an entry in the Belgian GP as a fourth Ferrari from a Belgian team, yellow being the race colors of that country.

I’ll bite – why would Enzo purposefully have his cars destroyed?!

Stanley Kubrick had all his original 2001 A Space Odyssey spaceship models destroyed at the end of production because he was afraid the studio would churn out cheap copies – which ultimately they did, much later – but they were forced to build everything from scratch.

I believe you; I just can’t imagine a reason why Enzo would purposefully destroy a car.