1998 Boxster 2.5 To 2001 2.7 Engine Swap Upgrade

[Erlinrys]

I'd appreciate as much feedback from experts in the process and the steps required to swap in a 2001 Boxster 2.7L engine in my 98 Boxster 2.5L (58K, Tiptronic Automatic.) I selected this 01 2.7 engine (see image below) to HOPEFULLY make this swap easy for the shop. I purchased a 01 Boxster engine 2.7L from a manual donor veh,. The motor was delivered. The shop will begin the engine swap process Tuesday.

The understanding I have in this swap is that I can drop in the 2.7 motor into the 98 Boxster and to utilize the 2.7 motor mount(s). After reading blogs and the Bentley Service Manual, and 101 Projects for your Porsche Boxster; My concern with the swap are as follow.

Wiring Harness (Can I utilize my 2.5 engine harness in the 2.7 motor?)
Throttle Body Intake Manifold (swap the 2.5 to 2.7 engine? Or keep the 2.7L throttle body? Is it really just as simple as running a 12v wire and another wire to Pin 59 into DME and then remapping it by taking into the dealership?) I'd like to avoid this process if possible, but if it will only cost under $400 and smooth operating Boxster, I can probably consider it.
DME (Can the 2.7 engine operate with 5.2 DME from 98 Boxster)
Transmission (Shall my Automatic tranny bolt into the 2.7)
I am hoping for my swap to be easy for the techs at the shop. What are some components and or methods required for a successful swap? All the input will be of much help. Thank you for reading.

Oh, FYI: I ordered replacement components such as Alternator (for Automatic), Starter, Engine Air/Oil Separator, Water Coolant, thermostat, Air Filter, Engine Oil Filter, Fuel Filter, Spark Plugs, Crank Seals, Oil Cooler O Ring Gaskets, Lower Upper and Idler Pulleys, Serpentine Belt, Three Gallons of Porsche Antifreeze.

And aftermarket Headers and 2.5 Electric Exhaust Cutout.

I would appreciate feedback from someone who’s done this set up on a 98 Boxster.

[itsnotanova]

I'm normally a pro-swap kind of guy but I highly recommend selling the 2.7 and finding a 2.5 or 3.4 instead. One of my best customer's an old retired guy who does nothing but tinker with M96 motors. He has even taken every class Jake Raby teaches about the M96/M97 motor. Heck he might have even taught Jake a thing or two as he's been working on Porsche motors for decades. Anyway, he tried putting a 2.7 in a 2.5 car. He ended up getting it to run but I believe he had to put the 2.5 heads, wiring harness and intake on the 2.7 motor and it still kept throwing codes. I'm not sure how much farther he's gotten with it though. He was doing it for fun. On another note, you're not going to see much of an improvement with a 2.7. That's a lot of work and $$ for little gain.

[Brian in Tucson]

I've never done the swap you're contemplating. If it were my car, if the 2.5 is running well, I probably wouldn't mess with it.

Some problems I see, you will have to use the automatic trans wiring. It's different from the manual, I believe. Your engine wiring will have to be transferred over.

Your 98 is mechanical throttle cable, the 01 is drive by wire so you may need to adapt the intake to use the older throttle body.

Will the trans bolt up? Don't know & don't know if you can transfer your flexplate over, either.

I'm in the process of putting an 00 to 02 2.7 into my 01 Boxster base with a 2.7. I know I'm gonna have to transfer the wiring over, and maybe the fuel rails. I guess I could have tracked down a 3.4, but it's all so complicated and I'm not an expert.

It seems to me, you're asking the wrong people. I would take a list of your questions and go see what your mechanic says. Your questions are valid concerns.

[Paul]

This most likely end with a bill higher than the cost of a 2001 2.7 Boxster and will most likely have code issues forever.

On my 98 here's a partial list of things that had to be replaced when installing a 2005 3.6 (yours will be similar):

gas pedal and new wiring
DME
Immobilizer
Radio
HVAC panel
Instrument panel
Elected not to replace the ABS, so lost cruise control

[78F350]

Originally Posted by Erlinrys

I'd appreciate as much feedback from experts in the process and the steps required...

I'm far from an expert, so I can't offer much help, but your post made me curious. Why are you doing this particular swap?

The shop will begin the engine swap process Tuesday.

I'm sorry... did you say Tuesday? as in this week, tomorrow? ..and you are asking these sorts of basic questions now? ...I mean, "NOW?"

I can drop in the 2.7 motor into the 98 Boxster and to utilize the 2.7 motor mount(s).

Yes, physically they fit and mount the same.

Wiring Harness (Can I utilize my 2.5 engine harness in the 2.7 motor?)

Here's another issue for you to consider: The Tiptronic transmission harness is bundled into the engine harness. If you don't use the 2.5's harness, you will need to tear it apart and rebuild it or find a 2.7L Tiptronic harness.

Throttle Body Intake Manifold (swap the 2.5 to 2.7 engine? ... just as simple as running a 12v wire and another wire to Pin 59 into DME ... and smooth operating Boxster, I can probably consider it.

Know what you are going to do before the shop tries to put the replacement engine in. (Are they experienced and do they have any suggestions about these issues?)
Throttle body: 1998 is actuated by a cable and gives position (load demand) info to the DME.
With the 2001, the gas pedal has a position sensor that gives load demand to the DME, which activates a servo on the throttle body, then a position sensor on the throttle sends feedback to the DME.
My guess is that the 5.2.2 DME will only work with the cable throttle and the 7.2 DME will only work with the eGas throttle. Programming and wiring will not fix that.
Either DME and throttle set-up will need custom programming to function well.
The 12v wire and DME pin 59 is specifically for controlling the flapper valve on the 2.7 intake's second cross-tube with the 5.2.2 DME. I don't think that pin 59 on your 1998 986 DME is going to be active without reprogramming. The engine will run without the flapper. It will have trouble meeting the correct fuel/air mix and have some flat spots in the power curve.
Unless you are ready to pay en experienced, skilled pro to get it all configured, swapping various parts will just be a poor compromise and give less performance than a proper 2.5L engine.

Transmission (Shall my Automatic tranny bolt into the 2.7)

Yes. TC and tranny bolt up, no issues.

... Alternator (for Automatic), Starter, Engine Air/Oil Separator, Water Coolant, thermostat, Air Filter, Engine Oil Filter, Fuel Filter, Spark Plugs, Crank Seals, Oil Cooler O Ring Gaskets, Lower Upper and Idler Pulleys, Serpentine Belt, Three Gallons of Porsche Antifreeze.

That's good planning. Other thoughts: IMS bearing and seal. Cam tensioner/adjuster pads.

My related experience is swapping a 2.7L manual engine into a 2.7L Tip and owning a 2000 S that had a 2.5L (1997) swapped into it before I bought it.

My advice.... Read Woody's (itsnotanova) post about a dozen more times and let it sink in. Don't take any action until after the holidays.

[Topless]

This is a pretty big can of worms actually and I don't know of any shop anywhere that has performed this swap without nagging issues and CELs forever. Figure maybe 100 hours of shop time to unravel all the niggling communication details between chassis, DME, and motor.

[Erlinrys]

Yikes. I was lucky enough to find an 01. I overheated my engine. And needed to replace it.

Originally Posted by Paul

This most likely end with a bill higher than the cost of a 2001 2.7 Boxster and will most likely have code issues forever.

On my 98 here's a partial list of things that had to be replaced when installing a 2005 3.6 (yours will be similar):

gas pedal and new wiring
DME
Immobilizer
Radio
HVAC panel
Instrument panel
Elected not to replace the ABS, so lost cruise control

[Erlinrys]

Oh man that sounds like a lot of work. I’ve worked with the shop owner and due to our friendship he agreed to $1,500 (to cover his tech labor cost and he informed me it’ll be about a week worth of shop work.)

It is going to be one of these task that we need to execute one way or another. I did a lot of research and I’m crossing my fingers I can make this happen.

I did also order a wire harness for the 2001 tip Tronic in case the wiring is not compatible.

I’ll keep you guys updated.

Originally Posted by Topless

This is a pretty big can of worms actually and I don't know of any shop anywhere that has performed this swap without nagging issues and CELs forever. Figure maybe 100 hours of shop time to unravel all the niggling communication details between chassis, DME, and motor.

[Erlinrys]

No. It’s a bit different for models under 01.

[Erlinrys]

Thanks for the feedback. See my input below.

Originally Posted by 78F350

I'm far from an expert, so I can't offer much help, but your post made me curious. Why are you doing this particular swap?


Had to replace Engine. i over heated the 2.5

I'm sorry... did you say Tuesday? as in this week, tomorrow? ..and you are asking these sorts of basic questions now? ...I mean, "NOW?"

Yes, it was Towed today at 8:15am. I did my research first. The idea sparked up from a guy name Roger from Auto therapy who works on Porsche‘s and then I began this unpractical process and based on my references it should work. Roger supposedly has compeleted these swaps and he informed me the DME actually reprograms itself without reflashing it.


Yes, physically they fit and mount the same.

Sweet!!

Here's another issue for you to consider: The Tiptronic transmission harness is bundled into the engine harness. If you don't use the 2.5's harness, you will need to tear it apart and rebuild it or find a 2.7L Tiptronic harness.

I did also order a 2001 automatic tip Tronic harness. Should arrive in the next couple days.

Know what you are going to do before the shop tries to put the replacement engine in. (Are they experienced and do they have any suggestions about these issues?)
Throttle body: 1998 is actuated by a cable and gives position (load demand) info to the DME.

They are not Porsche specialist. He operates Kash customs exhaust center and interlock services. He did not make any suggestions. I kind of went over this plan with him and we will see what happens.

Utilizing the 2.5 manifold and throttle body on the 2.7 engine and remapping my 5.2.2 dme hopefully solves this system. ( I am still also planning on running the 12 V wire and the other wire to pin 59 and try To place the 2.7 Throttlebody and manifold) 2

With the 2001, the gas pedal has a position sensor that gives load demand to the DME, which activates a servo on the throttle body, then a position sensor on the throttle sends feedback to the DME.

Yep. The 7.2 system. Using my 2.5 throttlebody hopefully resolves this problem


My guess is that the 5.2.2 DME will only work with the cable throttle and the 7.2 DME will only work with the eGas throttle. Programming and wiring will not fix that.
Either DME and throttle set-up will need custom programming to function well.

Yes, I’m planning to re flash the 5.2.2 dme to control the new engine.

The 12v wire and DME pin 59 is specifically for controlling the flapper valve on the 2.7 intake's second cross-tube with the 5.2.2 DME. I don't think that pin 59 on your 1998 986 DME is going to be active without reprogramming. The engine will run without the flapper. It will have trouble meeting the correct fuel/air mix and have some flat spots in the power curve.

If the 2.5 throttlebody and intake manifold do not respond appropriately I might have to encounter this problem or system with the 2.7 Throttle body and intake manifolD.

Unless you are ready to pay en experienced, skilled pro to get it all configured, swapping various parts will just be a poor compromise and give less performance than a proper 2.5L engine.

There’s only a 10 hp power gain difference. Will see.

Yes. TC and tranny bolt up, no issues.

Sweet!

That's good planning. Other thoughts: IMS bearing and seal. Cam tensioner/adjuster pads.

The engine that I purchased currenty has a serial no., On the IMS bearing, since there is a serial number on that ims bearing maybe the previous owners replaced it. Because I believe the stock I am as bearings do not bring serial number (see image)

My related experience is swapping a 2.7L manual engine into a 2.7L Tip and owning a 2000 S that had a 2.5L (1997) swapped into it before I bought it.

Oh wow. Yeah, it clearly referenced in 101 Porsche Projects that “Very early 1997 cars had non-programmable DME’s. If you have one of these cars you may need to purchase a new DME and matching immobilizer to go along with it. Immobilizer codes for these early cars are not stored in the Porsche Dealer information system, so there’s no way of linking the existing immobilizer to have a new DME. Don’t buy a 1997 if you are definitely planning on doing an upgrade as you might get stuck with one of these non-programmable th very early 1997 cars had non-programmable the Emmys. If you have one of these cars you may need to purchase a new DME and matching immobilizer to go along with it. Immobilizer codes for these early cars are not stored in the Porsche Dealer information system, so there’s no way of linking the existing immobilizer to have a new DME. Don’t buy a 1997 if you are definitely planning on doing an upgrade as you might get stuck with one of these non-programmable DMES”.

My boxster is 98.

My advice.... Read Woody's (itsnotanova) post about a dozen more times and let it sink in. Don't take any action until after the holidays.

I really hope it all works out. If not, does anyone want to buy a 01 2.7 Boxter Engine with 79k?

[Erlinrys]

Yeah I did read about the 2003 models engines switched to a vane-cell adjuster mechanism.

Thanks for the input.

Originally Posted by Erlinrys

I'd appreciate as much feedback from experts in the process and the steps required to swap in a 2001 Boxster 2.7L engine in my 98 Boxster 2.5L (58K, Tiptronic Automatic.) I selected this 01 2.7 engine (see image below) to HOPEFULLY make this swap easy for the shop. I purchased a 01 Boxster engine 2.7L from a manual donor veh,. The motor was delivered. The shop will begin the engine swap process Tuesday.

The understanding I have in this swap is that I can drop in the 2.7 motor into the 98 Boxster and to utilize the 2.7 motor mount(s). After reading blogs and the Bentley Service Manual, and 101 Projects for your Porsche Boxster; My concern with the swap are as follow.

Wiring Harness (Can I utilize my 2.5 engine harness in the 2.7 motor?)
Throttle Body Intake Manifold (swap the 2.5 to 2.7 engine? Or keep the 2.7L throttle body? Is it really just as simple as running a 12v wire and another wire to Pin 59 into DME and then remapping it by taking into the dealership?) I'd like to avoid this process if possible, but if it will only cost under $400 and smooth operating Boxster, I can probably consider it.
DME (Can the 2.7 engine operate with 5.2 DME from 98 Boxster)
Transmission (Shall my Automatic tranny bolt into the 2.7)
I am hoping for my swap to be easy for the techs at the shop. What are some components and or methods required for a successful swap? All the input will be of much help. Thank you for reading.

Oh, FYI: I ordered replacement components such as Alternator (for Automatic), Starter, Engine Air/Oil Separator, Water Coolant, thermostat, Air Filter, Engine Oil Filter, Fuel Filter, Spark Plugs, Crank Seals, Oil Cooler O Ring Gaskets, Lower Upper and Idler Pulleys, Serpentine Belt, Three Gallons of Porsche Antifreeze.

And aftermarket Headers and 2.5 Electric Exhaust Cutout.

I would appreciate feedback from someone who’s done this set up on a 98 Boxster.

[Erlinrys]

How is it running now?

Originally Posted by Erlinrys

Yikes. I was lucky enough to find an 01. I overheated my engine. And needed to replace it.

[Erlinrys]

Wow, that is interesting. Wish I had an S. And Wish I had 2.5L instead of the 2.7. Will see what happens.

Originally Posted by 78F350

I'm far from an expert, so I can't offer much help, but your post made me curious. Why are you doing this particular swap?

I'm sorry... did you say Tuesday? as in this week, tomorrow? ..and you are asking these sorts of basic questions now? ...I mean, "NOW?"

Yes, physically they fit and mount the same.

Here's another issue for you to consider: The Tiptronic transmission harness is bundled into the engine harness. If you don't use the 2.5's harness, you will need to tear it apart and rebuild it or find a 2.7L Tiptronic harness.

Know what you are going to do before the shop tries to put the replacement engine in. (Are they experienced and do they have any suggestions about these issues?)
Throttle body: 1998 is actuated by a cable and gives position (load demand) info to the DME.
With the 2001, the gas pedal has a position sensor that gives load demand to the DME, which activates a servo on the throttle body, then a position sensor on the throttle sends feedback to the DME.
My guess is that the 5.2.2 DME will only work with the cable throttle and the 7.2 DME will only work with the eGas throttle. Programming and wiring will not fix that.
Either DME and throttle set-up will need custom programming to function well.
The 12v wire and DME pin 59 is specifically for controlling the flapper valve on the 2.7 intake's second cross-tube with the 5.2.2 DME. I don't think that pin 59 on your 1998 986 DME is going to be active without reprogramming. The engine will run without the flapper. It will have trouble meeting the correct fuel/air mix and have some flat spots in the power curve.
Unless you are ready to pay en experienced, skilled pro to get it all configured, swapping various parts will just be a poor compromise and give less performance than a proper 2.5L engine.

Yes. TC and tranny bolt up, no issues.

That's good planning. Other thoughts: IMS bearing and seal. Cam tensioner/adjuster pads.

My related experience is swapping a 2.7L manual engine into a 2.7L Tip and owning a 2000 S that had a 2.5L (1997) swapped into it before I bought it.

My advice.... Read Woody's (itsnotanova) post about a dozen more times and let it sink in. Don't take any action until after the holidays.

[Erlinrys]

I wish you good luck. It seems as we both may encounter some dilemmas. Good Luck you might need a new DME. Read this

Boxster 2000 (2.7L & 3.2 S)

"The Boxster 2000 chassis can accept any Carrera 996 3.4L engine, or can use any Boxster engine from 1997-2002. In 2003, Porsche switched to a vane-cell adjuster mechanism to control the variable camshaft timing, and this system requires the later DME running Motronic 7.8. Unless you upgrade the car to use the later DME (very difficult), you cannot use any 2002 or later 996 Carrera engine or any 2003 or later Boxster engine. You can swap in any replacement engine of the same displacement from 2000-02 without having to remap the DME. (I.E. a 2000 2.7L Boxster with a blown motor can accept a 2002 2.7L engine with no remapping needed). Installation of a 3.2 Boxster 'S' engine would be an easy installation, but would require an updated map for the DME.

These cars ran the Bosch Motronic 7.2 system, which uses an electronic throttle body, linked to an electronic gas pedal (also known as drive-by-wire). When installing an engine into one of these cars, you need to use an electronic throttle body and corresponding crossover tube that matches that engine. (I.E. use the electronic throttle body from a 2000 or later 996 Carrera when installing a 3.4 engine).

If for some reason, you want to back-date the engine to a smaller displacement 2.5L engine, then you will have to use the injection system and DME map from a 2.7L engine. The 2.5L engine injection doesn't have the extra cross-over tube on the intake, and also has the cable-driven throttle body, which is not compatible with the electronic throttle 7.2 DME.

Installing a 996/997 3.6 or 3.8 engine or 2003-08 Boxster/Cayman engine is very difficult on these cars, as you need to manually update many other systems in the car to get them to work properly. These later engines used Vario-Cam Plus, which is a system for controlling variable valve lift. You need to run Motronic 7.8 in order to control the variable valve lift properly. It is possible to run a piggyback computer that independently controls the variable valve lift, but this solution is not ideal and is complex to implement."

Originally Posted by Brian in Tucson

I've never done the swap you're contemplating. If it were my car, if the 2.5 is running well, I probably wouldn't mess with it.

Some problems I see, you will have to use the automatic trans wiring. It's different from the manual, I believe. Your engine wiring will have to be transferred over.

Your 98 is mechanical throttle cable, the 01 is drive by wire so you may need to adapt the intake to use the older throttle body.

Will the trans bolt up? Don't know & don't know if you can transfer your flexplate over, either.

I'm in the process of putting an 00 to 02 2.7 into my 01 Boxster base with a 2.7. I know I'm gonna have to transfer the wiring over, and maybe the fuel rails. I guess I could have tracked down a 3.4, but it's all so complicated and I'm not an expert.

It seems to me, you're asking the wrong people. I would take a list of your questions and go see what your mechanic says. Your questions are valid concerns.

[Brian in Tucson]

I suspect my biggest problem will be R&R the engine and trans in my carport. Thanks for the "Good Luck" and I think we are all wishing you well, I think you're going to need the good luck, too.


Mine is coming out because the previous owner neglected it and it's been pretty hot at least a couple of times. My replacement is a factory rebuilt (50,000 mi ago) with an upgraded IMS bearing. Leak down variance is less than 6% and no apparent oil leaks--tho I did replace the crank seal and the rear main seal just because. $2300 plus shipping.

Keep us in the loop & Merry Xmas!

[Erlinrys]

Hey Guys,

A month after all the triumphs my 986 is on the road running strong and ready for day-to-day drives!!!

It sounds Nasty, and I will book it into the shop for the minor skirt incident.

After a couple mods, I was able to utilize my tip tranny from the 98 986 and swapped in the 2.7. We did need to modify the throttle from egas to 98 throttle system. Modified the injectors, intake, and other minor modifications in which required to take a minor step back, in order to create a custom fit.

Engine sounds obnoxious with the headers, custom exhaust, electric cut out, and other minor mods.

Happy Porsche! And F all the Nayers!!! Because I am sayer!!! haha jk..


Since you have taken your time to share information with me, I would like to share my story in how you and I connected.

Here is my story…….

I started this crazy engine swap from my 2.5 engine to 2.7 engine because I overheated my 57k Boxster engine. I needed to swap it out, knowing how expensive it was going to be I started my search for engines. I found one in Chicago, with close to similar miles, 10k plus, from a 100 r5 star review, Ebay Porsche Seller, and he also included all the four clips of the suspension. Since I also experienced a minor curb bump to the wheels and suspension in the driver side as you will see in the image of my Boxster at Porsche Bethesda.

Thousand, and thousands and thousandths of dollars later, and after all the “NAY, Sayers” in which my setup was not going to work, was able to get her running and sounding like a beast!

I finally booked her into Porsche Bethesda (one of our local service centers) to top her fluids, she’s back home.

I am also booking her into the body shop this week in order to repair the minor skirt incident, and the “one" matching wheel shall arrive within the next couple days, along with other minor mods.

Attached see the images when an officer securely delivered her to me. See images of triumphs during the swap process, her sitting happily inside the new 4 level Porsche Bethesda Facility, in our local Rockville Service Area.

That is my 986 welcome story, for trying to save a buck, she became stuck! Now, I am pleasing her with all the services to keep her running better and faster and unique, she’s my “UNICORN!."

Sorry, i am unable to add images, But i will figure it out. If not I can email them to you upon your request. Or, if anyone needs help in the swap from 98 Boxster to 2.7 I think I can provide material information for your swap.

[Paul]

From one unicorn owner to another: CONGRATS!

Hopefully you will have a code free future.

[Erlinrys]

No lights and no codes!

[Brian in Tucson]

Originally Posted by Erlinrys

No lights and no codes!

Is the difference in power noticeable?

Mine is within a day or two of firing up. I'm retired (late middle age) and I can do all of the work, I just daydream more than I used to. Engine is in, trans is all hooked up. Working on getting the hatch behind the seats closed up--finally bolted the a/c pump down and tried to install the wrong surp. belt, too big.

Glad to hear that your project went without a hitch.

I'm planning on firing it up day after tomorrow.

[Boxstard]

Originally Posted by Brian in Tucson

Is the difference in power noticeable?

Mine is within a day or two of firing up. I'm retired (late middle age) and I can do all of the work, I just daydream more than I used to. Engine is in, trans is all hooked up. Working on getting the hatch behind the seats closed up--finally bolted the a/c pump down and tried to install the wrong surp. belt, too big.

Glad to hear that your project went without a hitch.

I'm planning on firing it up day after tomorrow.

I'm curious too, if one has gone through those troubles to fit 2.7 on pre-2000 cars it got to have some reward... Or I'd just stick with 2.5 if not stepping up to 3.4.