Excellence Mag December 08: Outstanding M96 engine article

[Jake Raby]

If you want a better "Under the skin" understanding of the M96 engine, it's issues and it's enhancements you MUST get your hands on the Excellence December 08 publication when it hits the stands next month. If you don't subscribe to the mag, go to the local news stand and grab one!

A few months back the late Jim Pasha, Excellence Tech Forum Editor took a trip to our facility. During his visit we had many fine examples of M96 engine failures that we have documented on hand for him to view as well as some really trick new Boxster/996 engine parts from our line up.

Unfortunately, Jim passed away shortly after completing the article and this will be his last Tech Forum writing.

I have had a chance to proof read the finished version of the article (for technical accuracy) and I am VERY impressed with the comprehensive nature of the article and how it addresses the most important issues with all the variants of the M96 engine family used in the Boxster and 996 from 1997 through the current model year.

This is the best article I have seen to date on the topic of the M96 engine.
Huge Kudos to Excellence!!!!

[Lil bastard]

@Jake Raby...

Your endorsement means a lot... I've seen Excellence 'WhiteWash' a lot of issues regarding the 986/7... the M96 in particular.

It's good to know that they're finally seeing things more clearly... Maybe Porsche stopped being a Major contributor... or 'miracle-of-miracles', maybe Porsche is actually starting to acknowledge some of their own shortcomings with this series! Thanks again!

[Jake Raby]

The issues can't be ignored after what the past decasde has proven... Porsche can't cover up the fact that these engines have issues that weren't addressed as thoroughly as they could have been and that they still occur today.

I can't speak for Excellence, but I do know for a rfact that they wanted to shed as much light on the negative aspects of the engine (or more) than the positives and thats odd (highly respectable IMHO )for any publication.

I have had articles in magazines all over the World feature what we have developed for our air-cooled side of the house and most of them have been way less than impressive to deal with. In general they are a bunch of jack-asses that want someone to kiss their ass or give them something for free to get "ink" in their publication.

This is not something I have noted with Excellence in this M96 article OR the article they did on my air-cooled engine program in the December 2004 edition of the mag. They have been nothing but professional and wanted to share the truth about the air-cooled engines as well as the water-cooled M96.

The staff noted what we were doing and then asked us for content and some real world observations because the info was so little and hardly anyone has torn down more than 1-2 engines and few people have ever assembled one.
thats the problem with the engine, lack of understanding... Just like the 914 engine.

[70Sixter]

Man it is great to have Jake Raby on our side after doing soooo much for 914-4 engines.

In the world of 914ers Jake's famous engines are on everyone's dream list. Often only referred to by displacement by owners or wannabes, they are the ultimate 4!

I have to remind folks that Porsche has delivered flawed engines since the 356 days. The original 901s fouled plugs like crazy and ate chain tensioners, often causing horrible collisions between valves and pistons.

CD ignition fixed the fouling problem, but it took years for Porsche to really fix the tensioners while aftermarket mechanical tensioners carried the day for many people.

Then there were the exploding airboxes. If your 911 has a strange little pop-off valve on the airbox, that was the aftermarket "fix."

And so on thru the M96. I for one feel comfort in knowing my original engine can be rebuilt to fix the problems, not just sell me a new engine with the old problems.

So here's to Jake and Excellence!

I can't wait until that issue gets here.

[Jake Raby]

Thanks for the compliments!!!!
I am working hard to treat the Boxster and 996 with the same enthusiasm as I have (and still do) the 914 engine.

Lots to come in the future..

[Allen K. Littlefield]

Jake, in '03 Porsche added 8 hp by cutting what looks like a 'mouse hole' at the bottom of the cylinders so the air would not be compressed by the down stroke of the the piston but move into the adjacent cylinder which would be going up. Do you cut similar holes in your new cylinder installations? Seems like a rather easy way to up the hp without much technological stress. Interesting to hear your reply.

AKL

[Jake Raby]

Allen,
The mod that you speak of that was done by Porsche in the later engines is nothing new.. It dates back to the 356 days and has proven to be effective for high speed engines. I don't quite buy the 8HP claim of the mod, because as an engine developer I know what it takes to actually make 8HP and generally it's a lot more intense than this mod.

I have seen slightly measurable differences when modifying older engines in this manner for race purposes, but in a mild state of tune with the design of the M96 engine and the fact that it's a six cylinder the gains would not be that great.

The mod has more merit on a 4 cylinder engine as the firing order of the cylinders will put one piston at TDC and the piston residing adjacent to it at BDC simultaneously. This means the pressure displaced by the pistons moving in their bores is displaced 100% by the opposing piston and the "swapping" of this pressure between both bores is optimum.. A six doesn't have that characteristic on all cylinders.

So, to directly answer your question, we would only do this mod if the application demanded it, for higher revving performance engines. The later engines that had this as factory may get the mod if requested by the purchaser. before I see that 8 HP gain in my lab back to back with no other variables present (damn near impossible) I'll have a hard time believing that is the only thing the factory did to get the 8 HP... I'd much rather keep the bores as strong as possible..

The LN Nikisil plated cylinders add more than 8 HP to an engine alone and thats due to the super low tension rings they can use and the reduction in friction that they bring to the table. Between a set of Nickies cylinders and a performance valve job wel more than 8 HP will be present over stock and EVERY engine we build here gets both the aforementioned services, as standard.

[Allen K. Littlefield]

...for your take on that mod. If you will indulge me another question, since the cylinders are cast into the block, how do you remove the old ones and replace with new ones? Seems like you would have to re-cast the block around the new Niki's? Not wanting to be a pain in the ass, but I am fascinated with what you are doing and if my mill goes grenade you most likely will have a customer on your hands. You must have a way of removing the damaged cylinders etc. if you can re use the case. Old age wants to know...

AKL

[Jake Raby]

The methods used to lock the Nickies cylinders in place are proprietary and the biggest trade secret with what we are doing... This is LN's procedure and I have worked with them for over a decade, but they won't even tell me.

I can tell you that the old cylinders must be removed through an extensive CNC boring procedure that takes hours and about 300.00 worth of cutting tools are wasted per block to do the job! Using the CNC every block is done the same for excellent repeatability.

This is why the procedure costs as much as it does, but also why it works so damn well.

These aspects of the program is what make us capable of rebuilding blocks that have experienced a D chunk failure, pretty much no matter how bad the failure may be.

[Lil bastard]

I was certain that the old liners were bored out... didn't want to steal Jack's thunder. CNC is nice, but it could be done conventionally as well, though with some greater variance. There have been other cars where the liners were a negative fit (block had to be heated and 'expanded' to accept them) and these also needed to be bored for replacement.

One question about porting the bottom of the liners though. I can see where it would work well on the 356 air-cooled motor, but aren't the cylinders on the M96 water-jacketed? I believe thay are. That in itself could pose more difficulty.

[Jake Raby]

When standardizing the program CNC is mega useful and its much faster than boring cylinders by hand..

I do know that the process used to install the cylinders is labor intensive and has lots of Engineering and study behind it, and applied to it...

No matter how, it works and even if I knew exactly how it was done I'd never tell anyone! It's our ace in the hole!

[Allen K. Littlefield]

I have no trouble with trade secrets. The fact that you or whoever developed a way to bore these out and replace the cylinders is not to be revealed is OK with me. The fact that it works is the crux of the matter. I will follow Jake's work with interest as I am sure most of the rest of you will. Party on Jake and we will be watching your work with great interest for sure. Time will tell if your fix is the one that will last.

AKL

[Jake Raby]

Time is telling already.. The oldest of engines with the "fix" was done 3 years ago..

Skepticism is keeping people away, but guys that appreciate innovation can see what they need to understand why it works so well and why Porsche didn't do it at the factory.

To help combat some of the doubt and catalyze the development we are building a line of really nasty Turbo engines put on the edge and pushed to the limits with 28 channels of data logging in the car.... If we can put down 400 RWHP (maybe more) with a M96 engine and document pure abuse of it as well as daily driving without any failures, it will be really hard to argue with, or doubt. Proof will be in the data, oil samples and the associated blog where we'll journal the events..

That means 35-50K miles in a year on the street, and me putting a "shoe" that works for me in the seat for every DE held at Road Atlanta..

Thats exactly what I am doing now.. I don't care what else we break in the engine, as long as the classic IMS and D chunk failures are proven, we will have succeeded and done something that Porsche never succeeded with. They gave up and created the 9A1 :-)

We KNOW it works, but with an engine that has a reputation as bad as the M96 it will take years to prove that what we do works to the masses. Thats Human nature. It sucks for us, but we saw it coming and I have dealt with it for the majority of my life with the 914 engine..

I only like to work with bastard engines and things that no one else understands.

[Sputter]

Ever consider running for office.
I get pumped reading your posts. I'm really intriqued by your program and also seeing what kind of torque numbers we might be able to get.

Happy Thanksgiving from north of the 49th. (it's our weekend and yours isn't too far away)

Jim

[Jake Raby]

I am too direct to hold public office. I only believe in bold to the point statements and directions.. Opposite from what makes a successful politician..

Anyway, thanks for the compliments...