so i hope this didnt double post i dont think it worked the first time cause i wasnt logged in and when i hit post i lost it.
none of the setup has been bought yet so feel free to make recommendations if theres a better or easier way.
my idea is a 2001 or 2002 cavalier ohv with 5 speed manual as the starting point.
3400 engine will likely be out of an alero along with the upper mount, engine wiring and home made lower mount( should be about all i need right?)
- so i have no idea on where i would get an alero ecu reflashed to an impala tune or how that works. any help here would be greatly appreciated.
-if i get a stock ecu from an impala can i just get hp tuners for that ecu and tune out the passlock and auto trans codes so that it will run in an 02 cavalier 5 speed without throwing any codes?or would i still have to send it somewhere for reprogramming?
-any issues with running the impala ecu on a stock alero motor( differences in injectors or anything that might come up?)
-are there issues with running a bcm from a cavalier alongside an ecu from another car, i read somewhere your air bags wont work and there may be other issues if the vin numbers dont match. can the vin numbers be changed or would i have to swap in the impala bcm and airbag module as well?
thats all i got now if im missing something im sure someone will point it out. Thanks to everyone who put all the work into the stickies it is greatly appreciated!!!

canadianbacon wrote:- so i have no idea on where i would get an alero ecu reflashed to an impala tune or how that works. any help here would be greatly appreciated.

A dealer can reflash it, but you need a vin# from an Impala

canadianbacon wrote:-if i get a stock ecu from an impala can i just get hp tuners for that ecu and tune out the passlock and auto trans codes so that it will run in an 02 cavalier 5 speed without throwing any codes?or would i still have to send it somewhere for reprogramming?

This will absolutely work

canadianbacon wrote:-any issues with running the impala ecu on a stock alero motor( differences in injectors or anything that might come up?)

As long as you have the same type of injectors, there will be no problem (some 00-02 cars came with low impedance, some with high impedance--they look completely different, and have different connectors)

canadianbacon wrote:-are there issues with running a bcm from a cavalier alongside an ecu from another car, i read somewhere your air bags wont work and there may be other issues if the vin numbers dont match. can the vin numbers be changed or would i have to swap in the impala bcm and airbag module as well?

This has been done many times here now. You will not have an issue.

The best thing to do is to find a motor, harness, and ECM from the Impala. You can then grab a motor mount from a Grand Am or Alero. The mount will bolt right on to the Impala motor. They are identical. And since you're going to make your own lower mount, you could use the Impala lower mount (it's a plate that bolts to the oil pan, and has a bushing between it and a plate that bolts to the Impala subframe. You can simply remove the bushing and lower plate and weld a yoke for the dogbone in there)

Also, if you're looking to make your own mount, I can start you off with a lower mount that will just take a little modding. I still have some of my very first run of the lower mounts. They had a fitment issue that I wasn't pleased with, but can easily be modified. I have sold many of them already modified to use only 3 mounting points on the motor instead of 4, but I'm not really interested in modding any more at this point, so I'll sell you an un-modded one for $60 USD shipped (yes, to Canada), and you can mod it yourself. It just requires some minor redrilling because the holes didn't all line up properly. If you've got access to a decent drill press or a milling machine, there's nothing to it.

Thank you Mr. Quick. I guess im on the right track then. the salvage auction place near me just sold a 03 impala 3.4 taxi with 180,000 kms on it for 500 bucks so while they come up a little less often I should still be able find a donor car for a good price. My dads a big hot rodder/ muscle car guy hes got a whole fab shop for me to use. Last swap I did I had to make a bunch of alternator and a/c brackets and man is that a pain to make sure they line up properly. So i should be able to figure out the lower mounts. You guys did a really good job on the sticky I might pm you for the mount this summer once i get the project underway and save me some fab time maybe.( its good to know there out there).
The whole reason Im doing this swap is to get first hand experience in tuning and fuel injection systems cause my whole family is nothing but old school carb motors. And I got a 68 barricuda and a 74 plymouth i want to one day be able to swap in and tune a modern drive train. but a screw up on those could be a 5000 dollar screw up where with the 3400 i can get a whole parts car for less than 500. plus i dunno i got a weird thing for j bodys i guess

hey mr.quick ill just post it here.
i have already made my harness and im using an 01 alero engine harness combined with my 01 cavalier harness.
and i bought an 00 impala PCM. im almost finished with the swap. i plugged everything in and moved my serial data line over one pin and my gauges worked. but now the problem im running into is my fuel pump wont kick on. i didnt have time to look at it on the car. so yesterday i brought the harness in the house and unplugged the fuel pump relay control from the PCM connector and put it on the positive terminal on a 9 volt battery and then connected the negative to a ground wire on the harness and it energized the relay.
so i guess what im asking is, could i be running into the same problem as my serial data wire and the wire isnt in the correct pin?

Yes, I believe there are 3-4 wires that you are actually supposed to move. Check out the 3800 swap thread, as I believe it's mentioned there (even though it's a different engine, the Impala wiring information is pertinent)