So my header is off while the trans is out and since the header comes off more than never I decided it's time to stud the head so that I don't wear the holes out. Purchased a set ARP studs and nuts (400-8023) for the job. Last time I had the header off, I noticed some of the threads in my P8R already felt a little tired hence why I decided to do this next time around. I'm considering installing Helicoils in all 9 holes while I'm in there, or at least doing the ones that are worn already. Wondering if it's a good idea to be proactive, or should I stay on the side of "if it ain't broke, don't fix it"? What say you, fellow engine builders and machinists?

 

I would think it would be dependent on how comfortable you are with helicoiling. If you are comfortable doing it (practiced etc) then I don't see why you wouldn't.

The only tip I could share (which I think you probably already would do) is take a depth reading before starting just to be sure you don't over do it and dig into some galley or oil passage etc.

 

Thanks. biggest issue I see is that it's going to be hard to get to all of the holes with the engine in the car, even using the right angle drill. The AC lines are tough to get behind but maybe I can raise the front of the engine up enough to gain clearance. I'm pretty comfortable with the helicoiis, some times that can get get me into trouble by going overboard with a project lol. Just trying to take advantage of this quarantine and get things done extra thoroughly since there's no pressure to go drive the car, ya know? Thanks for the tip on the depth. I usually mark the drill with a piece of electrical tape at the depth that I want to stop at.

This drill should make things easier, still need to double check I have enough clearance for the tap handle and the insertion tool in there before I get going though.

 

Yeah, I don't think anyone would be comfortable doing that job with the engine in the car. I suppose if the radiator and condenser were removed for extra room but that opens a whole 'nother ball of wax...

Honestly, I would probably just take the time to pull the motor so as to not need to mess with the AC other than unhooking the compressor from the engine. Then you can have easy access. I mean, you are quarantined.....

 

Loctite the studs in the head. Save the HeliCoils for something else.

 

This is a fact lol. And since the trans is already out I’m basically 3/4 of the way there. Ahh project creep. But:

this is exactly what I was just starting to think is the best idea. A little dab of blue and call it a day. There’s a non-zero chance I’ll pull the head in the next 12 months. If it comes down to it I’ll do them at that point.

 

Timeserts?

 

Timeserts wouldn't have been any easier than the Helicoils (and there's nothing wrong with Helicoils for this application, so let's not get in to that) since the issue was tool clearance. I ended up chasing the threads in all of the holes and using a dab of blue Loctite, Should do sufficiently until if/when the head comes off. Goal was just to have studs to wear on by taking a header off once in a while as opposed to wearing out aluminum threads in the head.

 

Are B series different?

All my D's have had studs from factory for the exhaust manifold.

 

Later ones had studs on the outer two studs and bolts on the inner 7. This P8R head did, at least. It's been so long since I touched any others that I just don't remember exactly when they cheaped out.