Re: any gains going from 4.10 to a 4.30 gear
[Re: mopar dave]
#1188929
03/01/12 08:38 AM
03/01/12 08:38 AM
|
Joined: Oct 2005
Posts: 1,647 Ringtown, Pa.
Dartsport540
top fuel
|
top fuel
Joined: Oct 2005
Posts: 1,647
Ringtown, Pa.
|
I run 4.30 and 4.10 gears. No difference in et. , only a 200 rpm difference at the stripe. I usually run 4.30 gears, and the 4.10 are my extra set.
548 cu. in., Bill Mitchell Aluminum Block, CRT 727 auto trans, Alston Chassis. 8.981et at 149.46 mph. 1.204et - 60 foot, So Far....
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: mopar dave]
#1188930
03/01/12 09:31 AM
03/01/12 09:31 AM
|
Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
master
|
master
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
|
You can expect to run about .76% faster if your at 12.000 should hall to 11.90 10.55 to 10.46 ![](/ubbthreads/images/graemlins/Twocents.gif) That is assuming it does not cause spin or run out of wind top end and all else stays the same!
Last edited by Dodgem; 03/01/12 09:34 AM.
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: Otherlane]
#1188933
03/01/12 11:27 AM
03/01/12 11:27 AM
|
Joined: Jan 2003
Posts: 16,934 NC
440Jim
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 16,934
NC
|
Quote:
Is there a rule of thumb for gear changing? like one member said he didnt get any ET but there is a 200 rpm difference.is it for every gear change so does 200 rpms?
You can use the web calcs given above. But the pure gear change equation is:
RPM1:RPM you run with gear set 1 (G1) RPM2:RPM you run with gear set 2 (G2) MPH1:MPH you run with gear set 1 MPH2:MPH you run with gear set 2
RPM2 = MPH2/MPH1 x RPM1 x G2/G1
For example, If you run 130 MPH1 with 4.10 Gear1 at 7000 RPM1, and if your MPH doesn't change, ie MPH2=MPH1, then:
RPM2 = 130/130 x 7000 x 4.30/4.10 = 7341
The question of if your MPH changes depends on your car's combo. Also, in some applications the converter slip will change; which changes RPM
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: mopar dave]
#1188935
03/01/12 12:38 PM
03/01/12 12:38 PM
|
Joined: Apr 2007
Posts: 2,028 Trumbull,CT.
jim sciortino
top fuel
|
top fuel
Joined: Apr 2007
Posts: 2,028
Trumbull,CT.
|
Quote:
anyone have an ET gain going from 4.10 to 4.30 gear?
To make a long story short, it's like most other things......
It's combination specific, as there are too many variables to make a definitive response. What works on one deal, may not on another.
It takes time and money to cycle parts and make calculated/accurate comparisons, but that's what it takes to sort out any combination.
Bottom line......try it and see what happens.
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: mopar dave]
#1188937
03/01/12 03:21 PM
03/01/12 03:21 PM
|
Joined: Aug 2003
Posts: 43,528 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,528
Bend,OR USA
|
Quote:
anyone have an ET gain going from 4.10 to 4.30 gear?
My car, 518 pump gas stroker, 3450 lbs Duster, ran almost (within hundreds ands less than .25 MPH) the same with 3:73,3:91,4:10 and 4:30 Low tens at 128.+ MPH I do run the Mopar 2:77 low gear set in the trans so that may play into the results, the car usualy didn't spin no matter which rear gear was in it ,
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: Cab_Burge]
#1188940
03/01/12 09:39 PM
03/01/12 09:39 PM
|
Joined: Jan 2003
Posts: 16,934 NC
440Jim
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 16,934
NC
|
Quote:
My car, 518 pump gas stroker, 3450 lbs Duster, ran almost (within hundreds ands less than .25 MPH) the same with 3:73,3:91,4:10 and 4:30 Low tens at 128.+ MPH I do run the Mopar 2:77 low gear set in the trans so that may play into the results, the car usualy didn't spin no matter which rear gear was in it ,
Good example how different combos will respond differently. I had similar results with 3 gear ratios, 4.10, 4.30 and 4.56, the car didn't like high rpm and didn't need anymore torque multiplication at the start. Big torque motors with 3 speed auto transmissions may not be as sensitive as small cube/torque applications.
|
|
|
Re: any gains going from 4.10 to a 4.30 gear
[Re: tboomer]
#1188943
03/02/12 10:31 AM
03/02/12 10:31 AM
|
Joined: Apr 2004
Posts: 12,339 somwhere
smokinwoody
I Live Here
|
I Live Here
Joined: Apr 2004
Posts: 12,339
somwhere
|
Quote:
Pretty interesting...I would like to change the 4.88s out and go with a 4.30...
why so much gear Ted...how big are the rear tires...
|
|
|
|
|