Exhaust Manifold Bolts by Ray Dyreson

Performance exhaust headers have always been notorious for leaking at the gasket and the Fiero V6 is no exception.  My son’s 87 GT 3.4 with Sprint headers developed the dreaded “tick-tick” noise on acceleration.  We tried tightening the header bolts, which is not easy due to the bends in the header pipes.  This helped for a while, but the noise came back.  Checking the bolts showed they were loose again.  I learned from some local “muscle car” people that on their V8s they use special bolts with lock tabs to stop the bolts from loosening for good.  I called the manufacturer and found they make a kit for the 2.8 V6.  The bolts are stainless steel with both an Allen drive for quick turning down to seat in tight clearances and a hex head for final torquing.  A teardrop shaped lock tab then slides over the hex head and is positioned to jam up against the nearby header pipe.  This tab is held to the bolt by a C clip in a groove machined into the bolt head.  The bolt cannot loosen as the tab totally prevents it.  The hardest part of the Fiero installation is getting the C clips into place with little room for fingers.  You might want a few spare C clips.  I have not tried these on a stock manifold, but the bolts are 5mm shorter than the standard bolt.  This is desirable for headers and may work on stock manifolds, but would give three less threads to hold.  The bolt kit is available from Stage 8 Fasteners Inc., 64 Lois Street, San Rafael, CA 94901.  The phone number is (415) 485-5340; the web site is www.stage8.com  Part number for the 2.8-34V6 is #6910 with a cost of $45/set of 12 bolts. Ray Dyreson, Winnebago, IL.  NIFE member#132.


Our refresh-proof  hit counter reports: users since May 20, 1996.    

Copyright © 2001, Northern Illinois Fiero Enthusiasts, Inc. All Rights Reserved.
Send Comments to Webmaster.

Fiero Focus Online is a publication of the Northern Illinois Fiero Enthusiasts, Inc. (N.I.F.E.).  No copies of any part of this publication may be made, distributed, and/or sold without prior consent of N.I.F.E.  "Pontiac" "Fiero" the Pontiac symbol, and the Fiero badge are all trademarked by General Motors Corporation.  N.I.F.E is not responsible for any/all information provided herein.  Any and/or all adjustments made or information act on are done at the sole risk of the individual.