Author Topic: Picking gear for FED  (Read 5800 times)

Offline wideopen231

  • Hero Member
  • *****
  • Posts: 1911
    • View Profile
  • Your Best Time: 1/8 3.70@ 198 1/4 5.78@245
  • Your Engine: Hemi 526 ci alcohol
  • Your Track: Piedmont
  • Your Vehicle: 225 CMC FED
  • General Location: NORTH CAROLINA
Picking gear for FED
« on: April 09, 2014, 07:25:51 PM »
Trying to decide on which gear to go with for rear in fed.I have new axles,rotors and brakes on the way for car.If not for me having to have drilled axles with lightened flanges (7 to 8 lbs off total)I would have already gotten them instead of waiting for them.

Next is gear.I already have aluminum center (20 less than steel)and spool just need gear. Looking at 3.90 to 4.30 and leaning towards 4.11(also lightened another 2.25 lbs)
  My comb  526 aluminum hemi BAE heads,injected,sheetmetal intake and mag12, Powerglide hopefully 1.69 first and 6400 to 6600 stall.
15x14 -32 hoosiers

    Car 225" hopefully get it down to 1600# or less on the starting line.

   Any suggestions or comments welcomed.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline JrFuel Hayden

  • Hero Member
  • *****
  • Posts: 600
    • View Profile
    • Hayden Enterprises Speciality Wheels
  • Your Best Time: 6.02, 236 mph, 1/4 in 1973 Div 3 TF Champ
  • Your Engine: SBC, Alky, 403 ci, Best 6.99 @ 190 & 409 Hemi
  • Your Track: Bakersfield
  • Your Vehicle: 225" FED NHRA Heritage Jr Fuel
Re: Picking gear for FED
« Reply #1 on: April 09, 2014, 08:25:43 PM »
WideOpen, call Hoosier to see what the tire growth/ Dia will be at the speed you are shooting for, then go to www.csgnetwork.com/gearratcalc.html, and plug in the RPM, SPEED, and tire diameter, and it will give you a gear to run. Of course you can try different speeds, RPM's and tire sizes to get to the combo you are looking for.

Good Luck on your project,
Jon Hansen, Hayden wheels
Jon C. Hansen

Hayden Wheels

dreracecar

  • Guest
Re: Picking gear for FED
« Reply #2 on: April 09, 2014, 09:49:24 PM »
Each gear set change is worth about 200rpm top end

Offline rooman

  • Hero Member
  • *****
  • Posts: 559
    • View Profile
  • Your Best Time: 6.200/222.05 (1/4 mile--NT/F)
Re: Picking gear for FED
« Reply #3 on: April 10, 2014, 04:30:54 AM »
Trying to decide on which gear to go with for rear in fed.I have new axles,rotors and brakes on the way for car.If not for me having to have drilled axles with lightened flanges (7 to 8 lbs off total)I would have already gotten them instead of waiting for them.

Next is gear.I already have aluminum center (20 less than steel)and spool just need gear. Looking at 3.90 to 4.30 and leaning towards 4.11(also lightened another 2.25 lbs)
  My comb  526 aluminum hemi BAE heads,injected,sheetmetal intake and mag12, Powerglide hopefully 1.69 first and 6400 to 6600 stall.
15x14 -32 hoosiers

    Car 225" hopefully get it down to 1600# or less on the starting line.

   Any suggestions or comments welcomed.

Mark Vaught's blown small block car (aluminum block and heads) weighs in at 1575 lbs with a 200 lb driver and has 20 lbs of fire bottles, floater hubs, two chutes, aftermarket 'glide case. It also has an RCD front drive with an external oil pump and Pro Mag, double bead lock wheels, Racepack logger and dash and start line throttle controller so I think that you should be good on the weight.

Roo
Yeah, I am from the south--any further south and I would have been a bloody penguin.

Offline wideopen231

  • Hero Member
  • *****
  • Posts: 1911
    • View Profile
  • Your Best Time: 1/8 3.70@ 198 1/4 5.78@245
  • Your Engine: Hemi 526 ci alcohol
  • Your Track: Piedmont
  • Your Vehicle: 225 CMC FED
  • General Location: NORTH CAROLINA
Re: Picking gear for FED
« Reply #4 on: April 13, 2014, 08:55:49 AM »
Hope your right Roo man.A surprise to good side would be nice change if the shock don't kill me. So I already 24# to the bad because of driver.Was 280 and around 225 right now . 210 about my ideal weight. I did just maching on few piece and got another 4.8 lbs off.Cost only day of work and electricity for the mill.Plus getting a set of aluminum adjusters for rearend.

  Going to rebuild housing closer to Parks moly housing and thats 18 lighter than the one I have.

  Going with 4.11 gear.Figure best comprimise and matchs brother combo so I have spare if needed at no cost. But his third member is HEAVY compared to aluminum one I have.
« Last Edit: April 13, 2014, 08:57:21 AM by wideopen231 »
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot