Axle weight?
 

Is this a lot? 33 spline 12 bolt.
https://i.imgur.com/rblMvPD.jpg

Re: Axle weight?
 

I know people who had axles "rifle drilled" to lighten them, and saw zero E.T. changes.
Un-sprung weight is not as desirable as weight suspended, or "sprung-weight", I am told.
Weight changes on larger diameter components would be more noticeable due to effects on inertia.

Lighter axles, as I have been told, "can't hurt a thing."
I have some very bright friends. Wish I knew everything they know.

Re: Axle weight?
 

These things just seem awful heavy, I may have to call an axle company tomorrow to check weights.

Re: Axle weight?
 

When you are running a stick shift, Sooner or Later.....You will purchase Mark Williams axles....They weigh what they weigh.....

Re: Axle weight?
 

that is in 1/10 of a pound of my moser's . so it right in line.

Re: Axle weight?
 

Rifle drilling and scalloped flanges will result in a 17-25% weight reduction over a non lightened axle--- also keep in mind that a one pound reduction in axle weight is like a 15-17 pound weight reduction that the engine sees it has to try to overcome--FED 387

Re: Axle weight?
 

Thanks for the replies guys. I did call Strange today and in order for them to get me a side by side comparison they need the length of my axle, I'll get it and try to call back tomorrow.

Re: Axle weight?
 

Sounds like quite a bit, curious how you arrive at those amounts?

Re: Axle weight?
 

Mike, I found lots of info on this subject, as I've been looking. This particular article states that a Mark Williams superlite axle is 8lbs lighter than mine, thats a 16lb difference in axles! Seems like a lot to me.
https://www.markwilliams.com/aerp3.html

Re: Axle weight?
 

A cubic inch of steel weighs .283 pounds plus add in all the material in the flange multiply that by 2 and you get a number probably about 4-6pounds per side depending on axle length and diameter

Re: Axle weight?
 

The distance from the center of rotation is a factor in calculating the resistance the engine has to overcome, more than the total mass. Basic physics. A 12" 25lb. flywheel has less inertial resistance to overcome than a 14" 25 lb. flywheel as long as the mass is evenly distributed. Same with axles.

Unsprung weight reduction is the advantage of lightened axles, along with being able to distribute that weight more efficiently in the car.

Re: Axle weight?
 

Not necessarily true. If the engine has to overcome a certain weight it takes torque to do it . If the weight is less then less torque will be needed to overcome the lighter weight if the torque produced remains the same all things considered to be the same then it should translate into a quicker ET because the torque is now available to move an object instead of trying to overcome the weight of the heavier part

Re: Axle weight?
 

Not disagreeing with you, but the physical laws that describe the characteristics of this situation show that distance of the mass from the axis of rotation is more of a factor than the overall mass of the rotating object. While reducing the weight of the axles by rifle drilling has some positive gain, much more will be gained by looking at the rotating mass that is much further from the center of the axle. If I were only concerned with positive rotational inertial benefit and were considering cost, I would pay for lightened flanges before rifle drilling.

Re: Axle weight?
 

A simple study of some Applied Physics will always win over intuition driven or "some guy said" approaches. The matter of rotational inertia or inertia in general certainly falls in the problematic area. What Dwight has suggested is absolutely correct. Not just the mass of the item but where the mass is concentrated is most important and that is referred to as the radius of gyration on rotating components. The rotational inertia of parts can be measured by using a homemade torsional pendulum. The measurement is often easier than more complex calculations and is certainly more accurate. So doing things in this manner quite often is a bubble burster, but finding the actual truth will not only help your racing program but also save you some money in the process.
Regards,
HB2:)
Dissident

Re: Axle weight?
 

I was always told torque is what gets it moving horsepower is what keeps it moving. Look at a typical passenger car once its moving at 55 mph it takes very little HP to keep it moving especially when the engine is only running at 1600-2000 rpm maybe 12-17Hp

Re: Axle weight?
 

Dwight is correct.

Re: Axle weight?
 

Thank you for this, lots of info for me in the responses I appreciate it guys.

Re: Axle weight?
 

I doubt very much that you will see any decrease in ET with a lighter axle........
Theory and real life sometimes differ.
Dan

Re: Axle weight?
 

In the case of wanting (needing) to accelerate all the whirlygigs in a racecar, theory and practicum parallel as the issue is the classic application of F = ma. Force = mass x acceleration.



A rifle drilled axle doesn't help much (if at all) because the concentration of mass at the radius of gyration is not centered on the axle shaft itself. And tires are heavy and wheels might be light, but the concentration of mass is somewhat past the rim. Lots of money is spent on things that don't give a bang for the bucks spent.:D


Regards,
HB2:)
Dissident

Re: Axle weight?
 

the only real benefit to the light weight axles is if you need to get some weight off of the car to get closer to the minimum weight for the class then this will help in that area and possibly show some improvement in performance from the overall weight reduction. If you have to buy some axles anyway and you need to reduce weight then get the gun drilled and light flange axles. If not then performance gains will be minute.

Re: Axle weight?
 

I think what everyone is failing to understand here is that lightweight axles in and of themselves are not going to give you that"magical tenth" that everyone is pursuing. Lightweight mechanical parts of any type whether they be engine components, transmission components, rear end components, brakes, wheels etc are going to produce results. Some more than others. But when combined with MANY lightweight performance parts they "MAY" or "CAN" produce the increases in performance that everyone is looking for. The results usually come in the form of HUNDREDTHS of a second in lower elapsed time or TENTHS of a second in increased MPH.By combining the correct lightweight parts for your combination you will eventually get there. If you go with that approach you "MAY " get the desired results you are looking for by using certain lightweight parts and then again it may not work for you.You have to keep trying different things--- its called testing---Just because it did or did not work for the other guy doesn't mean it will or won't work in your car. Only testing will give you your desired results--FED 387

Re: Axle weight?
 

96 Camaro LT1 33 spline 12 bolt. Broke a axle a while back was a Strange regular full circle flange not drilled called Moser and asked for the lightest axles they could make $725 00 later they showed up at my door. Each axle was 8/10ths of a lb lighter than the old ones.hell I was more worried about the new bearings slowing us down than the weight picking us up.

Re: Axle weight?
 

Physics 101?

https://www.youtube.com/watch?v=UkNgWXpnyuI
What did he say?
https://www.youtube.com/watch?v=c5H605DpS38
Got an hour to spend?
https://www.youtube.com/watch?v=N92FYHHT1qM

Re: Axle weight?
 

I love these old videos. What we learn is heavy is better if it is located near the center of rotation.
Dan

Re: Axle weight?
 

So, fill our drilled axles with lead? :-)

Re: Axle weight?
 

If they are rolling down hill not under power the filled axle wins every time. Not lets put them on a flat surface and powered by a motor. I'll take the light weight ones every time.

Re: Axle weight?
 

Any reduction in overall weight would require less force to accelerate the car. The axle ,even though it’s spinning is still accelerated at the same rate as the rest of the vehicle. Is it possible that is why there is little to no ET reduction from a lightened axle or wheel ?

Re: Axle weight?
 

I was wondering how parts rolling down that board related to an engine having to accelerate that part. Small diameter & heavy will win that deal.

Re: Axle weight?
 

I was thinking the same thing.

Re: Axle weight?
 

I know it's a stretch.....it's covered in the third video, if your brain doesn't melt first. The acceleration of mass is.....the acceleration of mass.:D

Try building engines with a 50 lb crank rule.

Re: Axle weight?
 

Just curious or you all saying that single axle can weigh over 200 pounds are is there something wrong with that scale.I can lift one of my axles with one hand this axle I would need a engine hoist to get it in the tubes.

Re: Axle weight?
 

No, because the comparison is not between a 200 lb. axle and a 20 lb. axle. What is being said is that comparing the cost of a 14 lb. rifled-drilled, flange-scalloped axle to a "normal" 20 lb. axle is not justified for any performance advantage in most cases, if you are expecting the lightened axle to require less power to accelerate it. Physics shows that the benefit is extremely minimal.

Re: Axle weight?
 

Stated much better than me....ah, I. See, much better language skills.:eek:

Re: Axle weight?
 

My thoughts......


The most bang for the buck is running worn out slicks.....


Just sayin'