3.4 Project Begins!!!!

[CJ_Boxster]

interesting. I cannot wait to read ur writeup!

[JAAY]

So the project really begins...



Boxster 2.5 on the left Carrera 3.4 on the right

First off let me say these motors are heavy. 450lbs to be exact.

Below is the photo of the front motor mount mounting hole that is talked about in todd's swap. For some reason or another I do not have that on my boxster or the 3.4 motor. I am just pointing it out to show you. This is a photo of the 2.5 motor. The front motor mount is only bolted up with three 15mm bolts.



The 3.4 has the same three bolt locations so there there was no reason for me to concern myself with the extra bolt location. The photo below shows the stock 3.4 mount.



So I removed both mounts the 3.4 and the 2.5. The big difference is that the 3.4 is mounted with studs and the 2.5 is mounted with bolts. These need to be swapped. I just used a vice grip and spun out the studs on the 3.4 and used the 2.5 bolts. They were a perfect fit. The reason for this is the 2.5 mount is thicker than the 3.4 metal. Photo below to show what I mean.



To be continued in a few minutes... Dinner time..

[tholyoak]

Actually, all four mounting bolts are present on both engines, it is the cap screw to the right of your finger in the second photo. The old boxster engine mount on your 986 motor simply doesn't have the fourth mounting position. The first update of the mount many years ago was to add the fourth mounting position. I would recommend updating the front mount to the newest mount and use all four mounting points while you have things apart.

Also there are 4 mounting points on the 996 mount. Remove the stud of the one to the upper right in the photo and replace it with the cap screw at the same position on the front of the boxster motor. As you already found out the mounting studs on the 996 motor must be removed and you use the boxster mounting bolts.

It is too late now but you don't need to break open the AC system to remove the motor, just remove the compressor from the motor, that way recharging the system isn't necessary.
Have fun.

-Todd

[JAAY]

Thanks for the update about the updated mount.

I had no real method to my madness on the breakdown of this all. So next I started swapping some things from Todd's write up. Here are some photos of some parts that were swapped, and all need new gaskets. 2.5 photos first then the 3.4 photos.




So those two water outlets have to be swapped along with these also.




Here are two more parts that have to be swapped. The first on is the cap that is on the water pipe on the 2.5 motor and then other is the water outlet from the 3.4 These also need new gaskets.




Next I looked at the Oil Pressure Gauge sensor. If you want to keep it all in stock location you have to do some moving and plugging. I did not get to do this yet but I took some shots of what you have to work with. The sensor sits on the opposite side of the motor on the 3.4 than the 2.5 You could use the 3.4 sensor, I am just going to use the 2.5 sensor. If there is any question which is which the 3.4 sensor is the larger gold vdo sensor.




I took a photo of the plug to fill where the old sensor was. These plugs are on both motors just on the opposite sides.



Next I took off the intake manifolds. There is no real magic to this, just becarefull of the different vacuum lines not to break them. After I took them off I removed the oil filler tube from the 3.4 and removed the oil dipstick tube from the 3.4 I did not replace them yet with the 2.5 fittings. I have not taken the other motor apart yet to this point. I don't know if you have to do this but I pulled the alternator pulley and bolt to move it over a tiny bit to get to one of the 10mm bolts holing in the oil filler tube. The oil filler tube and dipstick need new grommets too.

[JAAY]

Here is a photo of the solenoid that Todd spoke of, the one that you have to run a wire from.. TODD I NEED A PIN Also a picture of the actuator and the internals of the plenum.




For now this is where I am at. I am awaiting gaskets from the dealer. All the parts in the photos are just mocked up for now for the photos and so I didn't loose anything. Todd informed me that I can use a clutch from a non-S 987. I am waiting for that too.

To be continued in another couple days..

[23109VC]

this is a REALLY great writeup. When you are all done, you should put all the photos/video together into some sort of large document. who knows, maybe you could sell it....

as these cars age, become cheaper, and there are more high mileage 986s that need motor transplants, there will be more people willing to do a swap.

I know that if I have my car long enough - and needed to do a new motor - and I decided to pay the money to do it - I'd for SURE spend the little extra to do what you did and put a 3.4L or 3.6L into my car. I have a 2.7 base - so I think I can only do a 3.4L... like you are doing.

your car is going to be FAST when you are done. you are going to go from about 200hp to about 300hp. overall weight of your car should not change much if at all - right?!?

you should outrun a new 987S. for a lot less money spent.

is that price for you rmotor standard or did you get some smokin' cheap deal?
$6400 for the engine doesn't sound too bad given the quotes I have heard just for stock motors! even if I had to do this and paid a pro/independent to do the labor - you could be OTD for under $15k - and probably add in some headers, ehxaust, new clutch while you're at it....

keep us posted on your project!!! what is your anticipated date of completion?

[JAAY]

I am only following Todd's write up that was done a long time ago. He is the man! The things I am posting are some of the things that I did not know needed to be done. I have headers and exhaust already for the car so that is all going back on. I am actually running out the door now to go order my clutch and more gaskets. Check back later on. I am going to maybe do some more work on the motors tonight and take more photos.

The price I got was not some insane price I don't think. You can find these motors on ebay for around 7k. And for your car you would want to do a 3.6 or a 3.8 I believe. Don't trust me on that. Thanks for the comments. Check back later on this evening after 9pm NY time.

As for completion. I would say in and running in the next 2 weeks. I need to find someone to reflash my ecu with the 3.4's. I don't know who I am going to use yet for that. I don't want to spend 1k on a reflash.