A HUGE thanks to Scott Conger for introducing me to Helicoil. I had a stripped out exhaust stud hole and this did the trick? Took less than 10 minutes. Car is MUCH more quieter with the new gasket. On the road again.

Nice job!

Heli Coils are OK but Time Serts are much nicer...

I've used both and for me they have worked equally well. The Time-Sert required a bigger hole to be drilled and it actually cut into the water jacket. A little dab of JB Weld and that was fixed.

I did used the Time-Sert on a hole that someone had previously tried to repair so that may explain the larger hole. Not sure about that. Surely did the trick quite nicely!

Good for you, Allen

BTW, my experience in Space Vehicles, I know that Helicoils are used and are perfectly adequate and tend to be my choice for minimal material removal during repair. In fact, with a Time-Sert, you will likely re-pull the threads out of cast iron, where Helicoils will expand/wedge when tightened and are now more robust than the cast iron by itself.

Additionally, what John said about size of hole required makes the Helicoil a perfect selection for this particular location/application on the T.

And, as John said, if the hole is butchered oversize, then a threaded insert may be the only choice.

Again, Allen, Kudos to you for a successful "first timer" installation

Stay away from locking helicoils. They like to chew up bolts unless they are grade 8.

Helicoils are the greatest thing since sliced bread.On my early cars I put them in aluminum housings such as oil pans and timing gear cases when the engine is rebuilt saves having to do it later. Cheers pete

Used a heli coil on one of my flywheel bolt holes. I secured it in with some Loktite........saved the day!

Somewhere on you-tube (and maybe it was here on the forum also) there is a comparison of five or six different thread repair methods. I seem to recall that the original premise was that Helicoils were weak, bad, and temporary repairs and suggestions that solid type repairs such as Timeserts were better. Surprisingly the Helicoils outperformed several of the "better" methods.

I've used both helicoil and threadserts that are similar to the timesert. I don't know about the timesert exactly, but the threadsert has a countersink and the installation tool runs through the insert and spreads the bottom end and locks it in place. I like them better where the hole goes all the way through. I like helicoils better in a closed hole. They work just fine if installed correctly, but can go through the hole if you have to disassemble and reassemble a lot. My $0.02...

I deal with a machine shop that does extensive work for a large aircraft manufacturer. The owner told me they put helicoils in every tapped hole in every aluminum part they make for these planes.

Let me start by stating that in another lifetime I worked for Helicoil. The Helicoil insert was designed to increase thread strength in lightweight parent materials (ie aluminum). The strength of the 18-8 stainless steel wire insert actually comes from it's flexibility in a tapped hole. The insert when properly installed remains flexible in the tapped hole. When the bolt is tightened the insert balances the bolt load much more evenly over all the engaged threads allowing for a stronger assembly. Without the insert, typically only the top 2 or 3 threads in a tapped hole carry the majority of the load. That is the major reason the assembly fails. You can take a bar of T-10 aluminum, drill and tap a 1/4-20 hole for a Helicoil, install the insert and break off the Tang. You can install a grade 5 carbon steel bolt into the Helicoil and actually when tightening it break the bolt without damaging the assembly. The broken bolt can be removed easily. Install another bolt and repeat! They also make a a twinsert (a system where 2 Helicoils are used). Scewsert is a locking insert (dyed red) that keeps the bolt from backing out. If memory serves me right you need a minimum grade 5 bolt so the locking coil doesn't damage the bolt. The hole needs to be drilled to the proper size and a STI tap used. You also can then torque the assembly the same as before. Do not use any type of adhesive in the hole as that will not allow the insert to perform properly. Maximum strength is achieved when the bolt threads completely thru the insert. There are 5 lengths of inserts per thread size. Bushings can also be used to repair damaged holes but normally require larger hole preparation. Just trying to present some facts on wire inserts. Use what you prefer!
Not intended to be a "infomercial"! Now I'll get my coffee....

Thanks for the information Tex, Good job Allen. Thanks to engineers that invent these things. I use all things available when it comes to our great hobby. Just where would we be without Helicoils, inserts, loctite, JB weld, silicone, the right stuff, ballance beads, Kevlar,stop leak, ballanced cranks, aluminum pistons, one piece valves, hard seats, new rods with dippers(I love these),new cams,high compression heads, bronze thrust washers, modern seals and bearings, and modern grease and oil.
These things keep our cars going at a reasonable price and in some cases, it is better than new!