engine replacement

[noy inthasane]

Hi I'm new to the forum and don't know much about Porsche engine . I have a 1999 Porsche 996 C2 3.4L without the electric throttle body I'm in the market to have the engine replace, and find a good deal on the electric throttle body engine . My question is can I switch the electric throttle body out and replace with mine so it work with my harness ? and how difficult isn't to do ? Please help want to be sure before I order.

[JFP in PA]

Originally Posted by noy inthasane

Hi I'm new to the forum and don't know much about Porsche engine . I have a 1999 Porsche 996 C2 3.4L without the electric throttle body I'm in the market to have the engine replace, and find a good deal on the electric throttle body engine . My question is can I switch the electric throttle body out and replace with mine so it work with my harness ? and how difficult isn't to do ? Please help want to be sure before I order.

Unfortunately, the answer is "maybe". From year to year, other changes were also made in the engine electronics and control systems that makes switching to other years problematic. One example would be the VarioCam system, some engines are VarioCam, others are VarioCam+ which use different electronics.

You need to be more specific about the year of the replacement engine you are looking at.

[noy inthasane]

Thank you for replying to my post, the donor engine I found was from a 2001 3.4L with 55k mile but it's an electric throttle body, my car is an 1999 Porsche C2 3.4L with cable throttle body. I hope you understand what I'm trying to do by swapping out throttle body and make the donor engine work ? Thanks
I also found another donor engine from an 1999 same year but this one is also electric throttle body and it's got 97k mile on it. Mileage are too high for me .

[JFP in PA]

Originally Posted by noy inthasane

Thank you for replying to my post, the donor engine I found was from a 2001 3.4L with 55k mile but it's an electric throttle body, my car is an 1999 Porsche C2 3.4L with cable throttle body. I hope you understand what I'm trying to do by swapping out throttle body and make the donor engine work ? Thanks
I also found another donor engine from an 1999 same year but this one is also electric throttle body and it's got 97k mile on it. Mileage are too high for me .

Here is where your problems start: Up to 1999, the 996 used the 5.2.2 DME engine controller; from 2000 to 2002 it used a 7.2 DME; and from 2003 on it used a 7.8 DME. The engine needs to match your DME, or you are in for some work to make another one function.

[noy inthasane]

Thank you for the info. This is very helpful I never thought about the DME engine controller can be so different from 99-2002, I always thought they were the same displacement and should be compatible, I guess I have a lot to learn about these engine . So only 1999 engine will be compatible to mine ?

[JFP in PA]

Originally Posted by noy inthasane

Thank you for the info. This is very helpful I never thought about the DME engine controller can be so different from 99-2002, I always thought they were the same displacement and should be compatible, I guess I have a lot to learn about these engine . So only 1999 engine will be compatible to mine ?

The problem is that Porsche never leaves anything alone for long. The 99 cars had no CAB Bus, the 01 cars used a partial CAN Bus for DME, dash, and other controllers; by 2002, most of the car's systems were on the CAN Bus network.

The VarioCam system also changed, at first being a single move of around 25 degrees, them became totally variable (VarioCam+), and then added variable valve lift to the system.

I would limit the search to a 98-99 engine to be on the safe side, unless you are ready to fund a lot of "one-off" custom systems fabrication, which ultimately reduces the car's resale value as no one but the person the made it work will know how to fix it.

[noy inthasane]

Thanks i will limit my search for a 98-99 engine . I did look into a motor swap cause i am planning to keep my car and want an engine that's more reliable and more hp. Renegade quoted me 28k to do the swap which is way over budget. I don't know any other shop that will do motor swap and still make my a/c and power steering work. If you know any other shop that do this type of work please let me know. Thanks again

[JFP in PA]

Originally Posted by noy inthasane

Thanks i will limit my search for a 98-99 engine . I did look into a motor swap cause i am planning to keep my car and want an engine that's more reliable and more hp. Renegade quoted me 28k to do the swap which is way over budget. I don't know any other shop that will do motor swap and still make my a/c and power steering work. If you know any other shop that do this type of work please let me know. Thanks again

$28K is just plain nuts; for much less than that you could have one of Jake Raby's best in the car.

You should be able to find a serviceable engine for $3-5K, throw in about $1-2K for upgrades (IMS, RMS, AOS, water pump, etc.) and another $2K for the install and debugging.

[noy inthasane]

I Thank you for all your time, I will look into a used engine or have mine rebuild by a well known Porsche shop. I really wanted to do a motor swap, but having the original motor running will be my last option.

[-GLIDE-]

The swap is not as complicated as outlined here.

The 99 c2 is the only 5.2 DME 996 (in the US) w cable TB. 99 c4 is 7.2 w/ electronic TB.

Buy any 3.4 you find. If electronic TB, you will have swap the following: TB, intake plenum, engine wire harness, AOS vent tube. It's really easy to do with the engine on a stand. I have all parts for a cable TB if you need - I have completed the swap twice. Really really simple...