Technical Information :: 6656S Tri-Y Headers

Steve Thompson's JBA Equipped '67 Mustang GTA 390
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JBA p/n 6656S headers are designed to fit the 67-70 390 GT Mustang equipped with a 390 GT 14 bolt cylinder head and factory transmissions.

These headers provide significant increases in torque and horsepower throughout the RPM range and allow for maximum ground clearance.

To help make sure you choose the correct headers, h-pipe and exhaust for your Mustang please refer to the chart below. If you still have questions, give us a call.

Note : : Some 69-70 Mustangs with fatigued factory shock towers and reinforcment plates may require clearancing.

:: P/N 6656S Fitment Guide ::
Specifications: Stainless steel 1-3/4" primary, 2-1/4" secondary, 3" dome collector, 3/8" laser-cut flanges
Engine Cylinder
Head
Block Trans. Trans X-member Clutch
390 GT 390 GT
14 bolt
Stock 4 spd/C6/Auto
(will not work
with T-5)
Stock Mechanical or Hydraulic
Motor Mounts Bell
Housing
Starter
Suspension Steering
H-pipe
Stock or Total Control Stock or
Scatter Shield
Stock or
mini starter
Reproduction upper A-arm
mounting studs may need to be clearanced.
Rack & Pinion - OK
Manual - OK
Factory P/S use 6656P bracket
Use JBA p/n
6655H