Helicoil BBC Exhaust Manifold Smog Holes?
 

Good morning all,

The smog hole threads on my manifolds are shot. Otherwise the manifolds are in nice shape with the correct dates.

Am I better off sourcing another set for my 1972 454 or finding someone to helicoil all eight holes?

Does anyone know of a reputable mechanic to refer me to? Approximately how much should this job run me?

Or perhaps someone has a set of manifolds 3989310 & 3989343 dated early 1972.

Thanks for your help!

Stan
1972 Chevelle SS 454 Convertible "W" code

Re: Helicoil BBC Exhaust Manifold Smog Holes?
 

Check out Keenserts. They are solid thread repair inserts versus the wound wire in a helicoil. You would have no chance for exhaust leakage with these inserts.

Re: Helicoil BBC Exhaust Manifold Smog Holes?
 

Thanks Keith. After looking at the site, may be a little too time consuming for me. I'm a CPA in the middle of tax season and don't have the time. I'd rather hand it off to a reputable shop and get it done right. https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

I am trying to get my car back together for Musclepalooza in May and am running out of time!

Re: Helicoil BBC Exhaust Manifold Smog Holes?
 

You may also want to look at Timeserts. They are solid also and easy to install. I prefer them over Helicoils. One other advantage to them is I have never had one back out like a Helicoil will do.

www.timesert.com

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Chris
1967 Yenko Stinger YS-199
Southeast of Disorder

Re: Helicoil BBC Exhaust Manifold Smog Holes?
 

I see a problem with this type of repair on the manifold port holes.First the holes would have to be milled not drilled to protect the flat seat at the bottom.Then a bottoming tap would have to be used to get the thread close enough to the seat then a correct depth insert would have to be installed.This repair would be a set-up nightmare.Has anyone out there ever repaired these threads?