16v KR crank knife edging

**velly_16v_cab** · 17-11-2007, 04:57 PM

i dont think u get more power, just the engine reponse better

**Preen59** · 03-12-2007, 05:00 PM

Originally Posted by gotrice

Reading through I cant believe that people still think that lightening the rotating mass gives you more power. It reduces the time taken to get to your peak power but you dont get any more horsepower. And yeah I know that I am going to cop a burning now lol.

Well, you're right, it doesn't actually allow the engine to produce more power because it doesn't change the thermal efficiency or the size of the charge, but it does effectively lower the drag on the engine, allowing the engine to pull through it's rpm range faster.

How's that for not burning you.

**99gti** · 03-12-2007, 05:05 PM

That makes purfect sense realy.

**gotrice** · 03-12-2007, 09:17 PM

There is so much love here that I am going to need a hug

**velly_16v_cab** · 04-12-2007, 09:39 AM

this was off my mate who does alot of engine building

Anyway. Lightening a crank. Hard one to explain really. He can either take a load of a little, but it has to come off the counterweights. Most tuners will cahmfer the bottom edge of the counterweight. It doesn't remove alot of material, but it will cut better through the oil and mist in the sump. The cranks I've done for myself and my mate, I've machined the whole side of the counter weight into a lon taper. I've aslo machined the flat edges at the end to get the crank equal along it's length as the factory unit is all shapes. All I can say is to take little at a timeand see how it goes. I's easy to ruin a crank in seconds either by machinin the wrong part, or even bending it between centres in the lathe!

he is currently running a 2.1 16v on twin 45's putting out over 200 bhp in a mk1

IT"S QUICK!!!!!!!!!!!!!!!!!!!!

**Preen59** · 11-12-2007, 09:03 AM

I only removed 6mm from the radius at 20 degrees. After thinking about it i may go a little more. As you said you can wreck a crank taking too much off so it's better to sneak up on it.

Here's a pic anyway.