French locks for exhaust manifolds
 

Who uses french locks on their exhaust manifolds? Any opinions on them? Supposedly they allow the outer bolts to have less torque and the manifold will be less prone to cracking. Some discussion of them here:
https://www.camaros.net/forums/18-en...all-bolts.html

Re: French locks for exhaust manifolds
 

They are mandatory of you want the manifolds to be leak and trouble free. Dont use manifold gaskets with them either. Usually the manifold needs to be surfaced for a tight seal.

Re: French locks for exhaust manifolds
 

They where factory installed on all the Ram horns I have ever seen. X2 on not using a gasket on them too!:chevy:

Re: French locks for exhaust manifolds
 

I have them on my truck, primarily because they were original to the truck. However, they should eliminate the possibility of the bolts loosening.

Re: French locks for exhaust manifolds
 

I use them but I never knew they were called French locks.

Re: French locks for exhaust manifolds
 

There were still on mine, had manifolds resurfaced and threw out the stupid gaskets. Reinstalled the French Locks after.

Re: French locks for exhaust manifolds
 

Those are a good idea, most just rip em off when installing new gaskets or working on the exhaust.

I have gaskets on mine, no locks, no issues, Mileage and opinion will vary. Oh I go thru and tighten them about every 6 months, needed or not.

Re: French locks for exhaust manifolds
 

Do you torque the middle bolts to 30-35 ftlb and end-pairs to 15-20 ftlb, to reduce cracking of the exhaust manifold? That is supposedly what the french locks allow you to do.

Re: French locks for exhaust manifolds
 

x2, thats why I opened this thread, I have them on my jimmy and just use copper coat on the block and manifold

curious as to the torque numbers