c1n3ma

Hi! I'm considering buying my first Porsche, and am currently looking at a 2006 Porsche Boxster Base. I'm looking to get a (relatively) reliable boxster and have settled on the 987.1 generation. Now I'm looking into subsets of that generation, the 2006 Boxster base has the 2.7L M96.25 engine, and the 2007 Boxster base has the 2.7L M97.20 engine.

I'm able to find a good amount of information on the two engines, but I can't find
- Reliability differences
- Redline on the M96.25 (Max RPM, online I've heard that the M96.25 only goes to 6800RPM compared to the M97.20's 7300RPM, which would be a decent difference)
- Fuel economy differences

Any information about those would be greatly appreciated. I'm trying to figure out whether or not it's worth it to wait for a 2007 Boxster, and the 06 is a 5-hour drive so I can't exactly stop by and take a look.

Thank you!

harveyf

You are of course aware of IMS bearing issues. If not, check out the PCA Tech Tactics youtube videos on the subject. Also technical papers at LN Engineering. I'm sure I'll be corrected if I'm wrong but my understanding is that the IMS bearing on the M97 engine is more robust, to the point that the failure rate is less than 1% (per LN). But it is not upgradable or repairable without pulling the engine and splitting the case. The IMS bearing in the M96 engine is not as robust but it can be upgraded with one of the aftermarket kits. Of course, buying a car where this had already been done would be the most cost effective. So that is one difference in the engines. I currently own two Caymans with the M97 engines. Knock on wood but they seem to be pretty bullet proof. Mine are S models so the base model is not as highly stressed, which is probably why you are looking at the base models. If it were me, I'd go with the M97 engine. The changes are very subtle but Porsche had a shopping list of things to tweak when they developed the M97. Why not take advantage of that? Yes, you will have a hard time finding discussions of these small detail changes. If you pm me with your email, I can send a Porsche document that may help you a little. They involve things like flow paths in the oil and cooling systems. BTW, the base engines do not have Varicam + (they have plain Variocam). This + is the arrangement that changes the valve lift on the intake valves. That is a big part of the horsepower difference in the S engine. So looking at the glass half full, this removes some technical complexity and thus should improve long term reliability. This would apply to either engine you are looking at.

Good luck with your search. There are a lot of Boxsters out there. Be patient and find a good one.

c1n3ma

Wow thank you for the detailed write up.

It was my understanding that the M96 engines in the late 2005-2006 Boxsters still had the more robust IMS bearing that was found in the M97. But I'm getting conflicting information on it. If it doesn't have the robust IMS bearing I doubt I will be purchasing the car unless replacement cost is factored in to the price.

Is it the Variocam + that gave fuel economy benefits? I'll also PM you my email, I'm a bit curious myself.

Thanks!

harveyf

Variocam advances the timing on the intake camshaft. Simply put, this allows the intake air to "keep up" as the rpms increase. It also generates less emissions at idle.
The + feature adds some trick lifters that can be extended mechanically to increase the total valve lift. This also increases the efficiency of the engine.
Both features certainly broaden the power band of the engine and allow a little higher rpm. Fuel efficiency is probably just a happy byproduct.
The article I can send you discusses this with some good pictures.

c1n3ma

I'd appreciate the article link.

But back to the IMS bearing, I thought that the 2006 had the revised bearing found in late M96s and M97s. However it's not very clear online and I can't find an answer one way or another.

Ari Kilpeläinen

Only early 2005 M96 engines had old style IMS bearing. I have 5/2005 base and it's bearing was recently replaced at 80k kms. It was almost gone.
There are specific serial numbers which have old bearing, but best way is just look and check it.

vitaminC

These cars are nearly 20 years old now- hard to believe! Don’t buy one with the expectation that it will be as reliable as a Miata and as cheap to repair.

What is the mileage difference between the cars you’re considering? Mileage, condition, and history are likely more important than the differences between 06 and 07.

Where are you located? What are your plans for the car?

c1n3ma

NYS,

The 2007 Boxster has 79,000 for $19,500 and 1 owner
The 2006 Boxster has 60,000 for $20,000 and 3 owners

The 2006 looks stunning with almost no signs of wear, the 2007 just sold

I can always wait for another one though. Looking for a second car that will be stored during the winter.

Also to add on, how effective are the xenon headlights when compared to the halogens on these cars?

hoster

I can understand your struggle as 2007 is one owner; however, 2006 is a great deal as well. Bought a 2005 (74k, one owner, a FL car, a larger IMS, 19 inch factory wheels, etc.) back in April, close to the price above but also included a hard top. Given the age, I would actually go for 2006 with lower mileage, especially if all records checks out, clean carfax, is from a non-rust belt state, no major issues with no immediate replacement of parts required (e.g., tires, brake parts) - I spent additional $2000+ (mostly for a new set of tires) for parts (e.g., brake pads, rotors) and tools (luckily I already had a low profile floor jack).

Here is what I found (I think here and/or other forums regarding IMS) in the past: 2006 has the bigger IMSB - while not 0% but "supposedly" significantly safer than the older / smaller IMSB - this gives us an excuse to go over 6000 RPM to propertly lubricate IMSB :-)

Per 2007 Porsche 987 Service Manual:
- SMALLER IMSB: up to (M96/25) 61.504715, up to (M96/26) 62.504094
- LARGER IMSB: from (M96/25) 61.504716, from (M96/26) 62.504095

As for bi-xenon, honestly, I don't really notice any "significant" difference (compared to our other cars with halogen). Plus I mostly drive the car during the day so far....
Yes, "they look cool" (my friend loves his) but not a go / no go item for me as I didn't even notice I had that option installed when I bought mine :-)

c1n3ma

What about the seats? That’s the last thing that worries me. The 2006 I’m planning to buy only has the base seats. How are they? Is anyone able to provide input on them?

Keith Guidus

We bought 2 owner 2006 base 5 speed with 43K miles and great CARFAX on 4/1/23. It was at Palm Springs Porsche and was $22,900 with a ceramic coating and alarm added($2k of crap). I called second owner and he verified info as they couldn't get in and out any more and bought a Macan AND his wife misses the car. We replaced the AOS and water pump as we don't like surprises. Dealer had R&R a brake caliper and replaced frunk/trunk switch panel and oil change. Tires were 2013/2015 dates so we put 3K on it on 2 PCA drives and an autocross and replaced Conti's with Michelin 4PS and its even more fun now. Just came back from 1,000 mile drive to Ca and got 28+ mog.
I'd go for lower mileage car if service records are identical BUT you have to love the color! Our other is a 1984 Targa bought new in May,1984 w/132K on it.

hoster

The seats are...seats. not your racing bucket seats but they "work" for me. In short, they are "average" without any significant signs of wear. If you are going to track, and or want different seats, you can just swap them out.