Yeap, still here and continue to work on my 3.5 v6 swap.. R&D takes a lot of time especially when you are in unchartered territory.

As i had mentioned earlier, I was toying with the idea of doing mods to the transmission (4T45e) to fit my needs. I was not in the mood of getting another transmisson. I have already gone through three tranny's.

I have relocated the transmission connector location. The stock location of the transmission connector interferers with the exhaust manifold and exhaust crossover. I am now happy with the final results.

First things first: I removed the side transmission cover to access the transmission connector. I removed the transmission connector from the transmission and cut back the connector housing.


Photo of the connector housing cut back.


Photo of stock transmission connector housing with 36mm expansion plug installed.



I have my son fabricate a new transmission connector housing. Basically, just an Aluminuim block, 5/8" thick that has been machined.



Photo of the transmission side cover modified to accept the new transmission transmission connector block.


Photo of transmission side cover modified with transmission connector block in place.



Photo of transmission case (exterior) with transmission connector block installed.



Currently I am waiting on a number of items to complete the connector relocation. 1. RTV specific for auto transmissions. 2. A new transmission connector and wiring harness. Once those items arrive, I should be able ot complete the connector relocation and move on to the next item, axles!!!

I know such fun. Hopefully I have figured out what items I will need to complete the axle installation.

I'm having a couple of electrical issues with my swap!

Question, for you guys that have done a simular swap did any of you develop a wiring pin out or diagram of the wiring conversion? If you have would you be willing to share that information?

Thank you in advance.

Back at it....................

I have scrapped the 4T45E idea! I am just not comfortable with the exhaust crossover so close to the top of the transmission cover (actually touching it). I have ordered another 4T65E. Should be in a couple of weeks.

In the mean time I have shipped my ECM & TCM to Sinister Performance for some custom tuning.

Recently I have worked on the fuel delivery system. No my design, copying anothers idea.

I am back to building a wiring interface harness for the 3.5 V6 to Fiero swap.

Basically, I have started over with building a harness. I was having some issues so rather than continue troubleshooting I decided to start from scratch. One of the main drivers is because I want to minimize the number of wires that go from the 3.5 into the passenger cabin. Basically, the only wires going into the cabin with be the wiring needed for the drive by wire, minimal BCM wiring (that will be restricted to the OEM Fiero ECM location), etc.

Just about finished building the wiring harness for the 3.5 v6 swap! Only have a couple of wires left to identify. Needless to say, it has been eating my lunch. The reason being is that I wanted to minimize the number of wires for the 3.5 v6 enter the passenger compartment. In case, you don't know or I failed to mention, I am not using a traditional instrument cluster for the swap. I wanted to retain my current IC (Instrument cluster) which is a 93 Buick Riviera IC (digital). Which means I will be adding the OEM Fiero engine sensors to the swap; i.e. Oil Pressure, water temperature sensors, etc. For additional monitoring of the 3.5 v6 I will utilizing an Android Tablet connected to the BCM via a Bluetooth connection.

For power to the 3.5 I will be using the following:



This fuse block arrangement will be the power source for the 3.5

I have completed building the Fuse block for the 3.5 v6 Swap and tested it.

I have updated the photo of Fuse Block assembly. The Fuse block assembly is scheduled to be installed in the Fire wall OEM battery location area.

This a basically a bump...


Still working on the wiring interface, needless to say, having issues. May have to back track??

One of the big issues is sorting out getting the cruise control to function as designed.

Question for those who have done or in the process of doing a 3.5 v6 swap....... 2009-2011


Where are you getting your tach signal??

IIRC, the N* uses a similar coil mounting ( with 4 coils ).

The TACH signal may come from the ICM (high level signal) or it may come from the PCM (low level signal)
If it is a low level signal, you may need a Dakota Digital unit to feed your Tach.

i just read this all the way through.i had a g6 convertible with a 3.5.great engine.3.9 sounds even better.hopefully someone will come out with engine mounts and a wiring harness for it in a fiero.i can't even weld. i have an engine hoist from when engines came out the top.

[This message has been edited by richard in nc (edited 07-06-2024).]

I am or was in the process of getting the engine ready for a test start & run! The engine is not yet in the car but still on the test stand. I want to get everything squared away before installing the 3.5 in the GT.

While in the process of getting ready to put oil in the engine and a new oil filter I discovered that the oil filter does not fit. When attempting to install the oil filter the filter hits the cradle not allowing installation. So, back to the drawing board. What I wanted to do from the get-go was install a "remote oil filter kit".

I have ordered a Remote Oil Filter Mounting Kit from NAPA, P/N #ATP 18428. On their web site NAPA indicates they guarantee fit for a 2010 Chevy Impala 3.5 v6.


We shall see when the kit arrives.