300 Steel Crank Mods

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Does anyone have any recommendations for modifications for a 300 steel crank? Balancing, oiling, knife-edging, lightening, etc.? Any recommedations for balancers? I want to build a strong bottom end for drag racing only, with the possiblity of power adders such as turbo or supercharger. The crank I have is a 1966 date code, which I think came out of a F600.

Thanks
Mark
 
As for balancers there's Fisher and just recntly fouind out that Innovators west has an application for the ford 300 more suited toward racing for around $375.00.IIRC FrenchtownFlyer had also metioned using a Fluiddamper balancer for a 351c aswell.
 
There was some talk a while back about removing the counterweights to get a 300 to spin up quicker for speedway use. search the old posts. i think there was even a website with a lot of information about it.
 
There a dirt tracker here IIRC he run a Legend car, he did that very thing posted pics.

Sorry can't remember his ID. DUH!
 
The dirt tracker website you are looking for is Ron Coons Vintage racing. I do not have the exact web site address you will have to do a search and hunt it down. Look in his tech section, he has some before and after pictures.

I have heard that some drag racers take as much as 30 punds off the crank. Locker room rumors....................as far as I know.
 
For what it's worth, on inliners.org site under Classifieds, Parts for Sale, Performance, Subject # 9, there is a liteweight steel 300 crank @ 54 lbs with a 3.98 (stock) stroke for $400. That's pretty light! I'd really wonder about it. The steel crank I got on EBay was about 93 lbs in the box. I have Ron's site in my favorites at home and if I remember correctly they drop 13 lbs off by cutting down the counterweights. They show before and after pictures and give a phone # to call for more info.

Darrell
 
Easy, oilfield roughneck simple.

Weigh the crank, use good scales. Want to remove 12#? OK there are 12 counterweights.

Cut first counterweight and grind and weigh until exactly 1 pound has been removed. Then repeat for each counterweight remove/ reduce weight exactly the same amount each time.

The crank is "zero" balance so if exactly the same amount is taken off each counterweight then it will be still in balance. Having a shop balance it would be just to verify or fine tune.
 
Someone tell me if I’m wrong, but I not sure if it is worth it to cut the crank weight for drag racing applications. I don’t question whether the engine will “Revâ€￾ quicker while the car is in neutral. It may help in very light cars in road course racing. Let assume we are talking about drag racing. For argument sake, assuming a standard transmission, once the clutch is engaged, the engine and the car become one. So, for the basic equation of F=ma, the rotational mass of the crank, flywheel, trans gears, etc., are added to the mass of the car. So, with this reasoning, it may be just as easy to remove some mass (weight) off the car. Now if every possible pound has been removed from the car, then maybe cutting some 10-20lbs off the crankshaft may be worth the effort. If we are on the subject of cutting rotational mass, then we could look at the crank pulley, flywheel, clutch/pressure plate, type of transmission, driveshaft/yoke sizes. Also, the 9â€￾ isn’t the most efficient rear end out there.

Along these same lines, this shows how much losses can be present in heavy transmissions, like the C6 or Turbo400. There is a lot of rotational mass along with the powers losses of driving the pump, etc.

In the past, I have heard of people lightening their fly wheel by removing a lot of metal off a STOCK flywheel and I would ask them how much they value their feet, especially when I hear they are not even using a scatter shield.

Also, it could be argued that the extra mass of the crank will store some extra energy, while the engine is “Revvedâ€￾ up, which would help lower the 60ft time with a standard trans while drag racing.

Just some thoughts

IMO
Mark
 
You are correct. The heavy crank has a flywheel effect and will help launch a standard. The rate of acceleration also helps. If the weight were the only factor everyone would be running heavy converters and flywheels. The only ones who still run heavy flywheels are super stockers. As impressive as it is to watch them they sure can be hard on drivetrain parts.

Look at wheel weight and think about it. Wheel weight makes a pretty big difference. This weight has a gear reduction helping to turn it. The crank sets at the heart of the engine. Anything you do to reduce friction, drag or inertia makes a difference. The weight reduction is the biggest difference. Next comes drag from oil and turbulance.

I have lightened many v8 cranks and it makes a big difference. I don't know if I would cut all of the counterweight off of a daily driver but I will always max out a race crank. I can remove 10 to 12 lbs off a sbc cast crank. It makes an impressive piece.

This is some of that free HP that cost a lot of money or labor to get. :lol:
 
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