PerTronix JBA Exhaust 6655S User Manual
Installation instructions and warranty information
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Installation Instructions
and Warranty Information
For ’67-’70 390/427/428 Mustang
Part#
Application
Notes
6656S 67-70 Mustang 390 GT
41, 42
6655S 67-70 Mustang 390/427/428/428CJ C6/C4
39, 41, 42
6654S 67-70 Mustang 390/427/428/428CJ 5spd
39, 41, 48, 49, 50
39 Will not fit standard 390 cylinder head.Head flange is designed for 14 bolt 390 GT cylinder head only.
41 Fits most rack and pinion conversions.
42 Requires JBA power steering ram drop down bracket for use with factory power steering.
43 Not designed for 5 spd trans applications
48 Fits 5 spd w/aftermarket cross member
49 Will not fit factory power steering.Fits manual steering.
50 Fits aluminum Shelby block
WARNING: These headers are legal for Off Highway use (except in California or states that have adopted Cali-
fornia emission standards) or Racing use (which may never be used on a Highway), or for use on pre emission
controlled motor vehicles/motor vehicle engines (pre 1974 domestic vehicles certified to California standards, pre
1974 domestic vehicles certified to Federal standards and all pre 1974 Foreign vehicles) Only.
Read all instructions carefully before attempting installation.
Rev. 04/09
Corporate Office: PerTronix Inc. 440 E. Arrow Highway, San Dimas, California 91773 * Phone 909.599.5955 • FAX 909.599.6424