Engine Drivetrain 1st Gen Cooper S Most liked posts in thread: Kavs Motorsport

So I've been reading quite a bit about this. knife edging is an old Hot Rodder trick. It does a few things. Removing some of the material to create the knife edge lowers the weight of crank, less to turn gives the engine less "drag" helping to increase the responsiveness of the lump. Less mass to spin allows for faster to speed.

Another advantage with the surfaces being polished is less friction when traveling through both air and oil. The oil has more drag than air does.

However, there is also much discussion on how oil flows off the back side.

This article on Aerodynamic Crankshafts from Race Engine Technology magazine is rather interesting.

I wonder if the money that would go into a crank such as this is better spent on a Dry Sump solution. Not only would the fluid drag be eliminated one could easily add more capacity to the system too.

 

the crank..

This is awesome!! KAV does outstanding work. His products are all over the Eu and the UK.

I am glad to see there is now a performance crankshaft that will be perfect for rebuilds and extreme power. Keeping in mind this IS NOT a stroker. He also has polished rods!!

I have been asked for years, on who does this... NOW WE KNOW!!

Just me...........................

Thumper

Crankshaft KAVS Motorsport

OOPS I didnt see the rods in the first post...Duh!! LOL

 

Just wondering.......could not any good performance shop knife edge, balance and polish a crank? Thump....what are the benfits to just doing all that to a OEM crank?

 

This is an OLD hot rod trick, Racing trick to add strength and more power from the stock parts.. The point of doing it to stock is just a matter of what people are looking for.. Just for grins , call a shop and see what they want to do it. Or what it would cost to do that to a stroked crankshaft??

I am sure if it is being done to OEM, it can be done to stroked. Me?? I really like smacking someones doors off with the stock stuff...lol! You??

The reasons to polish... knife edge, ect are in any performance engine build.

Just me...............................

Thumper

 

Good info.....but with our cars, R53, one would have to think that unless you are going to a completely different crank, a stroker, that spending the money on doing this to a OEM crank would not compute? I mean the stock crank is known to go to 500-600 WHP already

 

There are some great aftermarket cranks being built and available now for the Mini with all the above benefits. As of this writing I don't know of any drysump oil system for our cars. There is more to doing a drysump system correctly than meets the eye and an expensive proposition to boot.... But I would love to see one done well... 2cents

 

In a dry sump lubricated engine oil still falls to the bottom of the engine for collection, the reservoir is just smaller. That type of lubrication system does not address oil suspended in the air or adhering to rotating assemblies. The R53 crankshaft counterweights are positioned above the oil level (if not overfilled) and don't come in contact with the collected oil except under extreme g-load. Even a polished crank in a wet sump won't prevent cavitation in that circumstance. Crank scrapers and windage trays are cost effective measures to reduce oil cloud & oil adhering drag. The R56 engine variants have a stock windage tray BTW.

Polishing for the sake aerodynamic improvement is questionable.

 

The real advantage to a dry sump system is the ability to lower the engine in the frame. Lowering the engine lowers the center of gravity. Yes dry sump systems insure oil is available all the time to the pressure pump. The pickup will not get uncovered. If you had a window in the oil pan what you would see is a pool of oil spinning around the crank. Knife edging the crank and adding scrapers control the pool of oil. By reducing the weight of the crank and the amount of oil spinning around it causes the engine to accelerate faster. Less counter weight mass will add to the vibration. I have knife edged a crank before on a manual lathe. It takes forever, and the tool bit bouncing on and off the crank will drive you crazy. I hope whoever is doing this has a CNC lathe.

 

Let you all know the oil temp are much lower with our crank (+ some coating in the engine) compare to stock one.

For an example. 300 HP engine has 65 °C oil temp at driving in highway. The same gearbox, the same day, the same travel on stock bottom engine and 270HP car has 95-100°C.

The same OEM "oil cooler" on both cars.

When you pushing hard in the mountains. The oil in first one has 85°-90°C and the oil at 270 HP car goes even over 140°C!

Yes it works. Also 1 kg less in a rotation mass means something at accelerations.

Even movies come soon.
The top right gauge is oil temps in C.

 

Those pieces are real jewelry. Such workmanship. :drool