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Looking for performance Help

  • Thread starter Thread starter Chris H
  • Start date Start date Dec 28, 2005
C

Chris H

New Member
Dec 12, 2005
50
0
0
Crofton, MD
Dec 28, 2005
#1
  • Dec 28, 2005
  • #1
Hey all

I just purchased a 1966 mustang with a 289 Stock heads, 270H Comp cam (new valves etc..) K-code headers , electronic ignition, 40 series flowmasters. Mustang II front discs. Brand spanking new front suspension with new 5 leafs in the rear. also, new power boosted brake kit.

To my question, the stang has a rebuilt C4 with a rebuilt 8" peg leg 3.00 rear. I would like to change it to a posi unit and lower gears. I was thinking 3.55 or 3.73. I know this has been a question that has been asked many times but I want to get the right gear to match the 270H cam. My drving style changes from crusing at times to nailing it off the line against my buddies 69 camaro. So if you could help me decide what gear and where I should purchase the posi-gear unit from? Thanks all

-Chris
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Dec 28, 2005
#2
  • Dec 28, 2005
  • #2
3.50 would be a good all around gear. i would get a power trax from a place like national drivetrain. also look into getting a set of world products windsor jr heads, as bolting on a set nets you around 40hp. especially with your current combo.
 
S

steel1212

Active Member
Jun 24, 2004
1,180
0
36
Frankfort, Ky
Dec 28, 2005
#3
  • Dec 28, 2005
  • #3
yeah, your getting nothing from that cam with stock heads. I have ported heads on mine with a 280H cam but really need afr185s or something for that cam and my air gap intake to really perform. Alson on the gearing if you have a c4 your 3rd gear is 1:1 and anything above 3.50s and your going to be cruising at a high rpm.

go to www.randysringandpinion.com and click on the calculators and use the rpm calculator and see what you would cruising at. Another alternative would be to switch to a t-5 or aod.
 

LMan

Founding Member
Aug 10, 2002
1,246
0
0
Mom's basement
Dec 28, 2005
#4
  • Dec 28, 2005
  • #4
 
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