Manifold stud removal jig?

Kersidan · 5 Feb 2025

And with ti studs and nuts it doesn't matter if the studs seize in the block as it's the nuts that will undo off the studs if needed at some point in the future.

martin t · 5 Feb 2025

Uncle Monty said:
I see what you mean now , very clear in your pictures.
So you think the mild steel was there for strengthening the manifold ? When I looked at the manifolds bolts that had come out of my Boxster many years ago , it looked like the part that was in that mild steel section (6mm or so) was where all the corrosion had occurred and was the reason the head snapped off , it was much thinner in that section.
I did have photos but can't find them.

In precis it looks like the mild steel plate is to stop the stainless steel flange from warping, or if you look at it another way the mild steel plate is a giant washer.

martin t · 5 Feb 2025

https://www.ebay.co.uk/itm/20370785...teid=0&campid=&customid=&toolid=10001&mkevt=1 When I drilled out the bolts using my very expensive but worth every penny jig i installed those and topped them off with these https://www.ebay.co.uk/itm/17118221...teid=0&campid=&customid=&toolid=10001&mkevt=1. It is a lot less expensive than Titanium studs, but then try drilling out a titanium stud!

Using the above items, you, or the next owner will never have a problem with removing the manifold, should for example, they wish to fit a stainless steel manifold.

Uncle Monty · 6 Feb 2025

Good point, no idea why Porsche didn't fit studs from the factory

ndg · 6 Feb 2025

Uncle Monty said:
Good point, no idea why Porsche didn't fit studs from the factory

It will be cost and weight. Takes twice as long to fit a stud and then put a nut on that stud. Two parts will also cost more than one. The bolts are marginally lighter than studs and nuts.

Not ideal from a service PoV though!

924GT · 7 Feb 2025

martin t said:
In precis it looks like the mild steel plate is to stop the stainless steel flange from warping, or if you look at it another way the mild steel plate is a giant washer.

I’ve been scratching my head a bit with this one!
Unless I’m reading it wrong, the manifolds already on the car are stainless steel with as described above, a mild steel giant washer?
My little brain is going why not find out the thickness of the mild steel and replace the existing manifolds, after they have been cleaned up, with new stainless steel washers that would be pretty simple to have made up anywhere with the facilities to laser cut up some fancy washers from a drawing?

Hence, saving a small fortune in replacing your existing stainless steel manifold……with a more expensive stainless steel manifold?!

Am I missing something obvious?

tttc · 7 Feb 2025

924GT said:
I’ve been scratching my head a bit with this one!
Unless I’m reading it wrong, the manifolds already on the car are stainless steel with as described above, a mild steel giant washer?
My little brain is going why not find out the thickness of the mild steel and replace the existing manifolds, after they have been cleaned up, with new stainless steel washers that would be pretty simple to have made up anywhere with the facilities to laser cut up some fancy washers from a drawing?

Hence, saving a small fortune in replacing your existing stainless steel manifold……with a more expensive stainless steel manifold?!

Am I missing something obvious?

I had been thinking the same thing. How is the mild affixed to the stainless? Too thick to spot weld?

924GT · 7 Feb 2025

tttc said:
I had been thinking the same thing. How is the mild affixed to the stainless? Too thick to spot weld?

I’m going to get the car into my unit next week, drop the bumper off and all the head shields etc and start looking at what the issue really is.
Although, it still doesn’t get around the fact that I can’t get around spending £380 on the manifold jig!

martin t · 7 Feb 2025

The jig is worth every penny!

The mild steel plate is part of the manifold. I have no idea how it is affixed, suffice to say it is part of the manifold.

Interestingly the stainless steel manifold, such as the ones I have spare, are much thicker so the are a single piece and not a 2 piece construction.

As a generality ' if it aint blowing, it dont need changing'. This advice alone will save you £380. (please send my 10% commission for advice to the following bank account).

I have to say that drilling out the bolts is very theraputic, unless you are doing it laying on your back under the rear of the car.

martin t · 7 Feb 2025

martin t said:
The jig is worth every penny!

The mild steel plate is part of the manifold. I have no idea how it is affixed, suffice to say it is part of the manifold.

Interestingly the stainless steel manifold, such as the ones I have spare, are much thicker so the are a single piece and not a 2 piece construction.

As a generality ' if it aint blowing, it dont need changing'. This advice alone will save you £380. (please send my 10% commission for advice to the following bank account).

I have to say that drilling out the bolts is very theraputic, unless you are doing it laying on your back under the rear of the car.

Just to add that the original exhaust manifold gasket is a very thin steel item. When I refitted the original manifolds I used a conventional aftermarket thich gasket and the result was perfection.

Uncle Monty · 8 Feb 2025

Laying on you back under the car is actually a very good way of doing it cos you can push off the floor with your shoulders and keep a good straight force on the drill bit.
I have a lift but I ended up lowering it right down and crawling underneath

Mac996t · 8 Feb 2025

Rather than fancy stud kits you could just use normal bolts and change them every couple of years!

GMG · 10 Feb 2025

I use stainless steel bolts and they make removing the manifold very easy as I recently completely removed the exhaust to fit some 200 cel cats...these did require 4 new lambda sensors as the old ones weren't coming out!

nick38 · 11 Feb 2025

Thought I’d jump on this thread as it’s live. Thinking about changing manifolds for stainless items, the history suggests new manifold gaskets we’re fitted just over 12 years ago and bolts replaced, what’s the chances I’ll get those bolts out in one piece 32,000 miles later?

Kersidan · 11 Feb 2025

nick38 said:
Thought I’d jump on this thread as it’s live. Thinking about changing manifolds for stainless items, the history suggests new manifold gaskets we’re fitted just over 12 years ago and bolts replaced, what’s the chances I’ll get those bolts out in one piece 32,000 miles later?

I'd suggest slim if they were standard plated steel items but there's only way of telling. In the words of Clint Eastwood 'do you feel luckly punk?' But then it only takes one to shear and your'e on the slippery slope. Many would say if you haven't got a problem stay clear but them things can only get worse. I chose to bite the bullet and renew anyway.. a big job. But once done properly it's done for life.