ok i have been chasing a nasty idle, and a few other things with my ss i just got back from a buddy. the thing he neglected to tell me was that he f***in screwed up one of the sprak plugs and ate up all the threads... i know i fix it with a helicoil, but has anyone done it with the head still on the engine? or is that too dangerous? is it absolutely neccesary to pull the head off to do this job?

 

You don't need to pull the head off, simply coat the drill and tap with grease to catch the shavings, then I use a capillary tube attached to the shop vac to suck the cylinder out, lastly crank the engine over to hopefully blow out anything you missed.

The hard part will be getting the tap straight as it takes some practice doing this work to make it right, especially in-chassis. Maybe call around and try and find a shop that will do the work for you to make sure it's done right - that may be hard to find as in our area we are the only shop that will do it in-chassis, most mechanics pull the head and bring it to me for repair on the bench.

 

yeah thats what i am worried about is getting it crooked... i thought about just taking off the head anyways and redoing the whole top end.. but havent made up my mind ... thanks for the info

 

I have some Mustang buddies that do it in car, but on the Modular motors it's a LOT easier with the plugs going in vertical.

 

to be honest i am a mustang person at heart, i have owned several and love the modular motor. i have done a few of those helicoils, but have never done anything with a sideways spark plug thread..lol.. they(4.6's) dont make half the power but i miss the modular stangs. they were so easy to work on

 

I recently had this issue and went ahead and pulled it off completely. Didn't want to go sideways just like you stated.