CLASS RACER FORUM

CLASS RACER FORUM (https://classracer.com/classforum/index.php)
-   Stock and Super Stock Tech (https://classracer.com/classforum/forumdisplay.php?f=4)
-   -   Rotational Weight Question (https://classracer.com/classforum/showthread.php?t=57642)

HP HUNTER 04-17-2015 11:21 PM

Rotational Weight Question
 
Lets say you have C/SA 69 Camaro 375/396, If you ran a conventional 12 bolt with a steel spool non gun drilled axels and ran 10.50 with 1.36 60 foots, if you built a 12 bolt with 35 pounds less rotational weight and ceramic bearings, how much would you pick up?

GTX JOHN 04-18-2015 02:08 AM

Re: Rotational Weight Question
 
I think if you picked up .01 in 60 that would be a lot.

Ed Wright 04-18-2015 07:10 AM

Re: Rotational Weight Question
 
I put an aluminum spool and lightened gear set in mine, and found nothing. I don't waste my money there anymore.

Tom Meyer 04-18-2015 08:07 AM

Re: Rotational Weight Question
 
My thoughts are, you could pick up more by having your rear end square in the car and all moving parts on it move smoothly with no binding. The right lube and how much is also important along with having the gears properly set up. I also don't think you could get 35# out of a 12 bolt and if you could all that it would help would be sprung unsprung weight. Tom

HP HUNTER 04-18-2015 09:26 AM

Re: Rotational Weight Question
 
Quote:

Originally Posted by Tom Meyer (Post 468090)
My thoughts are, you could pick up more by having your rear end square in the car and all moving parts on it move smoothly with no binding. The right lube and how much is also important along with having the gears properly set up. I also don't think you could get 35# out of a 12 bolt and if you could all that it would help would be sprung unsprung weight. Tom

What lube do you run?

HP HUNTER 04-18-2015 09:30 AM

Re: Rotational Weight Question
 
Quote:

Originally Posted by Ed Wright (Post 468087)
I put an aluminum spool and lightened gear set in mine, and found nothing. I don't waste my money there anymore.

Do you think a foot brake combination might have different results? I appreciate all opinions, just trying to learn.

tj310 04-18-2015 09:54 AM

Re: Rotational Weight Question
 
I remember a saying that was attributed to Colin Chapman

A gram of reciprocating weight is worth an ounce of rotating weight

an ounce of rotating weight is worth a pound of chassis weight

Take that with a grain of salt. ---Trevor

FED 387 04-18-2015 02:36 PM

Re: Rotational Weight Question
 
I was always told that rotational weight is equal to 4 times the actual weight---- that means that for every pound the effective weight that the engine is trying to overcome would be 4 pounds--- now this may depend on how great the diameter of the object is--- in other words if you have an item that is 2 inches in diameter the rotational weight difference will not be as significant as say an item that is 12 inches in diameter where it should be greater--FED 387

Ed Carpenter 04-18-2015 04:24 PM

Re: Rotational Weight Question
 
I asked this before. I was told to spend my money under the hood. All that crap isn't worth .05

james schaechter 04-18-2015 06:06 PM

Re: Rotational Weight Question
 
I think if you have the car flogged out, tuned out and drive it perfectly every time, buy that stuff. I do think it can help over time,but it is never one thing, it is all of the things. If there is no more HP to be had, start there. If you can't make minimum weight and you can save unsprung weight why not?( expensive though) You need the good stuff though. I have heard of guys trying some aluminum spools and the deflection hurt more than any weight savings. If you are not hampered by any pesky performance rules, just hop up the bullet. I agree, very small gains for big money. Walk the Comp pits.mthose guys know.


All times are GMT -4. The time now is 03:56 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright Class Racer.com. All Rights Reserved. Designated trademarks and brands are the property of their respective owners.