Jake and Charles Navarro invented the sport, encountering multiple ways not to do a retrofit before they found the optimum solution to the problem that even Porsche originally said was not possible. Several others, including Pelican, tried to come up with simpler or cheaper DIY ways to address the problem, all of which cut corners and led to problems, some fatally. The problem for the indie shops doing retrofits was always the teary-eyed customers that flat bedded their cars to the shop after screwing up the project, only to be told that their engine had to come out and apart to fix what they had done to them with these simpler and cheaper techniques.

Probably the dumbest was an early (Wayne Dempsey days) Pelican procedure that did not use ANY cam holding tools, but instead used Allan head set screws threaded into the back of the engine case thru the IMS flange bolt holes to try and hold the chains by putting pressure on the gear on the rear of the IMS shaft in a vain attempt to lock the chains. Unfortunately, that rear gear is pressed on and slip prone, resulting in that gear being pushed forward on the IMS shaft, and the shaft suddenly jumping upwards and to the right due to the tension on the chains. When this happened, cam timing was lost and there was no way to reposition that gear without taking the shaft out of the engine. We probably encounter a dozen or more cars in this condition that were brought to the shop.

Long story short, there are a lot of wrong ways to try and attempt this retrofit, and one proven right way that now even Porsche has adopted. Do it right and you do it once; do it wrong and you will be spending some serious $ to get out of the hole you created.

My comment was in the context of replacing the chain tensioner pads, which it is logical to do if the engine is out of the car. If only the IMSB is to be replace one lock would be enough.

Yes, I read and reread and reread yet again Pelican's description of the set-screw method and it seemed flaky to me, so I'm relieved that I'm not alone in that assessment.

I think I'll be fine if I follow Jake Raby's method to the letter.

Ah, that makes sense, Grant. I do plan to replace the Variocam wear pads after the IMS bearing, and I've borrowed the official kit, which comes with its own set of cam locks.

I've been notified that my "IMS Solution Bearing Replacement Kit for Dual Row IMS 97-01 Boxster 911 Models" has shipped! Let no snowstorm or other act of God delay its delivery (or there will be whining).

While waiting for the Solution to arrive I've been researching bore scoring, second only to IMS bearing failure in causing catastrophic failure in Porsche engines. I own a borescope and had planned to eyeball the cylinders through the spark plug holes, as I have done with conventional engines. However, I've learned from LN's pre-qualification procedure and from videos at flat6innovations.com (Jake Raby's company) that this method is not sufficient, that one must remove the sump cover and examine the cylinders from underneath. D'OH! There is a ray of light, though. It seems M96 engines are less prone to bore scoring, because the pistons are cast rather than forged (https://www.youtube.com/watch?v=G7idZe6qAtg 9:45).

So I'm idling in neutral at the moment. Perhaps my almost OCD-level perfectionism will force me to unbolt the sump cover and have a look. But doggone it, as I've complained before, making this new engine bulletproof is like yanking a piece of yarn on a sweater. It's only 1 pm here on the West Coast, but it feels like beer thirty. And I don't drink.

In the interest of settling the questions about which and how many cams to lock, here are a couple excerpts from LN's IMS Solution installation manual:

"Lock right side (when facing flywheel) camshaft in place using IMS pro tool kit camshaft timing jig. Use the shorter cam lock on 5-chain and longer one on 3-chain engines."

[Note from LWG: The exhaust cam is not specified above, but an accompanying photo shows the bottom cam, the exhaust.]

"Some installers prefer to lock camshafts on BOTH banks of the engine. This is a practice that is not required, and is a matter of personal preference. With the crankshaft, and one bank of camshafts locked, all timing chains will be held tightly in the proper position for a successful IMS Retrofit procedure."

Crank locked at TDC and bank 1 exhaust cam locked down. Well... the cam's almost locked down — a drill bit is holding the lock in place until I can obtain the appropriate bolt. Anyone happen to know the specs on the bolt I need?

I didn't have a 24 mm open-end wrench to turn the crank with, so I used a large metric crescent wrench. (I own a lovely matched set of metric and SAE crescent wrenches.)

http://986forum.com/forums/uploads02...1737765965.jpg

The hydraulic tensioner under the air conditioning compressor has been torqued so much I couldn't break it loose with a breaker bar on the 32 mm socket without the engine moving on the lift table. The engine is positioned exactly where I want it; I don't want it to move. Tapping the breaker bar with a heavy rubber mallet tomorrow should break it loose. I call that an "old-school impact wrench." I've marked each tensioner and its housing with matching numbers — 1-1, 2-2, 3-3. After the tensioners are removed, I'll stuff plastic wrap in their respective holes to keep stuff out.

Then it will be time for sacrilege: defacing the crankcase by cutting a notch for the oil fitting on the Solution's IMS flange. Talk about an invasive procedure! However, I acknowledge the necessity. There seems to be a variety of methods for creating the notch, but I plan to use the LWG method, which involves tungsten-carbide burr bits, my new Ryobi, and eye protection.

It is the same bolt that holds the pressure plate to the flywheel. Since you are not supposed to reuse these you should have some available.

Thanks, Grant. Good idea. But the pressure plate and flywheel are attached to the old engine, which I haven't dropped yet.

The bore scoring inspection? Locking up everything, including me of the unecssary steps/personal preference? God didn;t gift you with OCD for nothing. Don't be wallowing in your regret a year from now with " shuld haves". Just do it. All. Cover every base. Listen to your OCD.

Now... from where did you purchase the set of SAE/metric crescent wrences. I have the SAE, but after spending several hours looking for the metric... zero. Thanks.

I've been searching high and low for left-handed wrenches, myself.

Actually, I don't have full-blown OCD, I have a much less severe version called OCPD — obsessive-compulsive personality disorder. It's OCD-lite. I strive for perfection, but if perfection is unattainable for some reason, I'm practical. I can say the hell with it. However, you're probably right that I should just bite the bullet and remove the sump cover and scope out the bores. I'll save it until last.

I picked up the set of metric and SAE crescents at Bed, Bath & Beyond, in the Beyond department. Alas, they closed all their stores in 2023, so you'll need to find another source.

Bed, Bath & Beyond also had a huge selection of those, but they sold out pretty fast.

My old-school impact wrench loosened the tensioners with no trouble. Now I'm ready to perform the sacrilege on the crankcase. Can't happen until I have the Solution in hand, however. I need its flange in order to precisely mark where the notch will be. The alteration is sacrilegious, true, but it shall be done with precision, and not like the one below, which looks like it was done by someone who got carried away with nibbler pliers. Once material is removed from the crankcase, it ain't comin' back.

http://986forum.com/forums/uploads02...1737850143.jpg

"Measure twice, cut once".............just take your time, mark what needs to be removed and you will do fine.

And just make sure you make the opening large enough to be able to get a socket on the fitting with the trans in place as if anything ever happed (fitting comes lose, etc.), you can service it without removing the trans. Several people only made the opening just large enough to install the flange cover with the fitting installed, but not enough room to get a socket on it or turn it, which means you are pulling the trans out to get at it.

Always plan ahead...............

Yes, I plan to make the notch a millimeter or two larger than the socket, so marking the cutout will need to be accurate.

Also, you can't ruin a project by taking your time, but you definitely can by being in a hurry. I don't have a reputation for being the slowest mechanic on the planet for nothing.

EDIT: LN says much the same thing, but more succinctly. From their Post-Procedure Notes: "You can’t rush success, but you can rush failure!"