By   June 28, 2015

Porsche Boxster 986

Porsche Boxster 986

The early Porsche Boxster (986) is an incredible value in the sports car world. It is a well balanced car that can out handle just about anything and you can find plenty of very good well maintained examples for under $10,000.

The 1997-1999 Boxster isn’t very fast in a straight line compared to more modern cars. Porsche claimed a 0-60 mph time of 6.7 seconds (although multiple magazines that tested these early cars managed times around 6 seconds flat) and a top speed of 149 mph. These figures aren’t bad, but every now and then it would be nice to have just a bit more power. One option to up horsepower is to drop in an engine from a 911, but does it make sense to do this?

Click past the jump (or scroll down if you came directly to the full article) to find out more about the Porsche Boxster 911 engine conversion.

In the early 986s a 3.4-liter from a 996 or a 3.2-liter from the pre-2002 Boxster S are fairly easy to put in. They do require a few fairly minor modifications and an update to the car’s DME.

The stock 2.5-liter flat-six in the early 986 puts out just 201 horsepower versus 250 horsepower for the 3.2-liter engine and 300 horsepower for the 3.4-liter. Obviously, most would go for a 3.4-liter power plant, but there is one downside. It has become somewhat hard to find good used engines.

Still if you take your time and look around you can find engines in good condition with about 50,000 miles on them. We’ve seen engines like this cost about $6,000 while we’ve seen plenty of 3.2-liter engines with similar mileage and condition for about $4,000.

If you figure you can find an early 986 in good condition for about $8,000 and then buy a used 996 engine for $6,000 (some places may have a core fee that you have to figure in) then you have $14,000 into a car. Now you may be able to sell your 2.5-liter engine for about $2,000 depending on condition and mileage which could bring the cost to around $12,000.

Now you should figure $2,000 – $4,000 in other needed parts and to get the DME upgraded. This brings the total to about $16,000. Providing you are mechanically inclined and do most of the labor yourself.

An early 996 costs about $20,000 – $25,000. So, this would seem to make sense financially, but we forgot a few things.

In the 996 you’ll get a 6-speed transmission, upgraded brakes and suspension. These are all things that you’ll want to consider when upgrading a Boxster to have a 996 or Boxster S engine. Depending on what upgraded parts you use, you could spend upwards of $10,000 on these parts. On the low end estimate about $5,000 to get a used 6-speed transmission in good condition, minor brake upgrades and some minor suspension upgrades. While you are upgrading the engine and possibly the transmission it is also a good time to put in a new clutch as well as upgrading the Intermediate Shaft (IMS) bearing to the updated style.

So, that puts the cost of upgrading an early 986 to use a 3.4-liter 911 engine to about $21,000-$26,000 with all the recommended upgrades. This means you can save yourself a lot of work and purchase an early 996 for about the same price as doing all of the upgrades to a Boxster. For more information on upgrading to a 911 engine check out an article featured by our friends at Pelican Parts.

Does it make sense to put a 911 engine in a 986 Boxster? Yes and no. It depends on what you want. Do you want a car with the 911 power and performance, but in a mid-engined well balanced roadster package or do you want Porsche’s flagship the 911?

Let us know which would would prefer in the comments.

  • Doc423

    Good article…food for thought. A big advantage costwise would be doing the work yourself. Another advantage would be having a rare and unique car, a mid-engine 911, so to speak, which in itself would be worth more on the market, I would think.

    • David Hurth

      Definitely, the more you do yourself the better the cost. You could also do some of the upgrades to the suspension, etc after doing the engine upgrade as you get time and money. I’ve heard of some that just upgrade the engine and claim everything is fine. It probably depends on how you drive the car as to how much additional work may be required. If you are going to do some track days, then suspension, transmission and brake upgrades would be a very good idea. If you just drive it on the road, then you may be able to get away with less (at least for a while).

  • Cbad-box

    I recently purchased a clean 99 3.4 conversion for $11,000. I am not that mechanically inclined so I paid to have typical wear and tear items replaced, IMS upgrade, clutch and the motor resealed and new tires. Mileage is at 86k, it came 05 wheels, cayman-S exhaust and PS9 suspension. Still has original 5 speed. Very fun to drive, sprited, and I love the sleeper aspect. Total outlay is around $19K. I am very pleased with this project. Search for “The Quick Cuban” April 2010 issue of Porsche Excellence Magazine. Great article for this type of build.

  • Ronald Breeze

    I love my 1999 986 with its slightly modified 2.5L motor. Sure it’s “underpowered” in most peoples view but on twisty, curving roads it keeps up with anything out there. The exhaust note on the 2.5L’s is a symphony of flat 6 technology. I took it to the drag strip at Sears Point and made it to the semi finals and only lost by .355 seconds or I would have been in the finals. Everyone seems to want more hp but a finely tuned 2.5L with an upgraded suspension and brakes is a joy to own and drive.

  • Ronald Breeze

    I love my 1999 986 with its slightly modified 2.5L motor. Sure it’s “underpowered” in most peoples view but on twisty, curving roads it keeps up with anything out there. The exhaust note on the 2.5L’s is a symphony of flat 6 technology. I took it to the drag strip at Sears Point and made it to the semi finals and only lost by .355 seconds or I would have been in the finals. Everyone seems to want more hp but a finely tuned 2.5L with an upgraded suspension and brakes is a joy to own and drive.