Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541247
08/25/18 01:47 PM
08/25/18 01:47 PM
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Joined: Aug 2003
Posts: 43,285 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,285
Bend,OR USA
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Do you know how much the weight difference will be? Adding weight onto the drive line is different than adding it into the suspended car I use to race in NHRA stock, the common thought was that each hundred pounds removed from the car was worth a 1/10 ET decrease in the 1/4 mile, rotating weight was thought to be worth more
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541257
08/25/18 02:22 PM
08/25/18 02:22 PM
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Joined: Dec 2005
Posts: 11,668 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,668
Fulton County, PA
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Interesting conversation on this subject in the S/SS tech section on Class Racer right now. You may be surprised how little it effects it. Polar moment is less than the tires and the wheels make relatively few revolutions in a 1/4 mile. I think the difference in unsprung weight and total car weight in a full blown race deal is where the benefit really shows.
Last edited by CMcAllister; 08/25/18 02:28 PM.
If the results don't match the theory, change the theory.
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541267
08/25/18 03:04 PM
08/25/18 03:04 PM
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Joined: Oct 2007
Posts: 4,210 New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,210
New York
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The "this much weight = this change in ET" formulas are fictional.
Boffin Emeritus
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541283
08/25/18 04:17 PM
08/25/18 04:17 PM
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Joined: Dec 2005
Posts: 11,668 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,668
Fulton County, PA
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I believe the RW power to total weight ratio has a direct, predictable influence on MPH numbers, give or take some depending on aero, etc. The weight of certain reciprocating components is part of the total weight, but the influence of changes of those components on ET is hard to predict.
A lighter reciprocating assembly in the engine or transmission will accelerate quicker. But wheels are not being accelerated to thousands of RPMs. However, taking 40 or 50 pounds out of the wheels is 40 or 50 pounds out of the total weight and the unsprung weight which effects suspension efficiency. 50 pounds should make a noticeable difference, regardless where it is removed from. It may be more of a difference coming out of the wheels.
If the results don't match the theory, change the theory.
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541304
08/25/18 05:10 PM
08/25/18 05:10 PM
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Joined: Dec 2006
Posts: 2,118 Byron, NY
W.I.N. Racing
top fuel
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top fuel
Joined: Dec 2006
Posts: 2,118
Byron, NY
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To answer your question, in your case not enough to say so.
'01 P1500, Blown/Inj BAE,/Veney ,Bruno/CS2,Dana 60 '01 Dodge 3500 S Cummins Auto, Fresh air kit, 4" Exhaust, '05 Dodge Magnum R/T - Too Much to list '60 Willys CJ5 '01 International LPX - Project,DT466, Allison '64 Plymouth Valiant, Inj 528 Hemi, 2spd
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541420
08/25/18 11:21 PM
08/25/18 11:21 PM
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Joined: Feb 2016
Posts: 12 Minnesota
ThatDarnCat
member
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member
Joined: Feb 2016
Posts: 12
Minnesota
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Just my experience - I had been bracket racing my '67 Shelby for about 12 years with a set of old Motor Wheel Spyder aftermarket wheels, probably about some of the heaviest wheels, with a heavy cast aluminum center and a chrome steel rim, and then switched in the mid-'90's to a set of Bogart "Drag-on-Fly" Stars, spun aluminum wheels very similar to the old Motor Wheel Flys, and some of the lightest drag race wheels available at the time. Car ran consistent low 12's, about 3450 lbs with me in it at the time. Same size rear wheels, 15x8" with the same 28x9" Good Year slicks. Fronts changed from 14x6" Spyders with bias ply street tires, to 15x4.5" Bogarts with Good Year Front runners. I did weigh the wheels at the time, but the info has long since been filed away somewhere, but the difference was significant. I needed to change to longer wheel studs for the Bogarts and the only company making the special studs for the early Mustang front discs was ARP, and they were out of stock for a short while, so I wasn't able to change both front & backs at the same time, and the change was made part way through the race season at the time, so I had some good data going. I put the new rear Bogart wheels on, and the difference was noticeable immediately on the first burnout, the rpms spun up much quicker, and the car ran consistently one tenth ( .10 ) quicker. By the next race I had the new front Bogarts and lighter front runners on, and saw very little change in ET, nothing measurably different that weekend. So that's what I found, the lighter rears made the biggest change. You're not making as much of a weight change as I did, your current wheels will be a bit heavier than the Bogarts, and the Cragar S/S's are likely a bit lighter than the Motor Wheel Spyders, So my guess would be you will slow some, maybe 5 hundredths (.050)?
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541522
08/26/18 12:11 PM
08/26/18 12:11 PM
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Joined: Jan 2004
Posts: 8,341 fredericksburg,va
cudaman1969
master
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master
Joined: Jan 2004
Posts: 8,341
fredericksburg,va
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I've been watching the other post also, my thinking, maybe lose some at launch. The only way to really tell, add 25 lbs to the car and make a run back to back, with and without. See if it's worth worrying about, it's only a number anyway. Can you tell the difference between 11.50 and 11.60 without a time slip? IMO Cragars are the best looking wheel of all time, run em!
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Re: Cragar wheel weight opinion for racing
[Re: WS68SSC]
#2541623
08/26/18 04:33 PM
08/26/18 04:33 PM
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Joined: Dec 2003
Posts: 4,952 northwest USA
NANKET
master
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master
Joined: Dec 2003
Posts: 4,952
northwest USA
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This is the question from the post on classracer Anyone have real world honest results in E.T. reduction when replacing standard type centerline wheels with really light wheels? So he already has light wheels, and wonders if lighter yet wil help. Some have done it and say no.m some say any rotating weight reduction will help. I say those cragers will slow down the ET.
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