When I was growing up my grandpa owned and loved impalas. He had some of the most beautiful SS'* I have ever seen. When the 9c1 and 9c3 Impalas come out he was crushed. The FWD v6 only platform was insulting to him. I personally think they have potential looks wise but I see potential in everything. Anyway, I have an 01 Impala and my gears have been turning for a while on how to put a RWD v8 in it. I own a rather large salvage yard so I have and come across any part you could imagine and have the facilities and knowledge to do a major car build. I want to do it for my grandfather. I have a few ls3 engine and trannies and as fate would have it I recently came across a 1950 Plymouth deluxe p19 coupe. Its rear wheel drive and has the same wheelbase as my 01 impala! I'm aware of the fabrication requirements to fit a rear diff and drive shaft to my impala. Would it be easier to put the body of my Impala on the Plymouth frame and install the ls3 or fabricate motor, trans, rear diff, and axle mounts? The Plymouth was in a garage under a cover for 32 years and still rolls would run with minor engine restoration.

Wow, I am hardly qualified to even post in this thread, however I will share what my thoughts are on this. I can only recall 1 successful RWD conversion, and that was a 1 off performance showcase car back in the day (92-95 Bonneville) where they essentially took the body, and stuck it on a caprice chassis.

I think in the process you will pick up a fair amount of weight, but it will likely be a necessary evil, because the unibody is not designed to fire power out the back. Same goes with firewall and drive line room.

If you do this, you will be a hero. Others have toyed with the idea of the AWD Versatrak system which uses the same transmission, or even a similar Volvo setup, but in the end, nothing ever came of it.

Maybe he would go for a 2014 SS with some impala badges stuck on it? LOL.

I love modding. Of course, as the old saying goes..."Anything is possible with a welder and money". With that said, it would take a custom made engine cradle/suspension for the front. Cut a line down the middle of the underside of the car/spread upwards. This is to facilitate the RWD. Adding in the rear axle is just a matter of welding in/bolting mounts for the axle and shocks/springs etc. There is no cut/dry method to modding. Thus why its called "custom".

But remember one thing. The EPA has a general rule about engine swaps especially when it comes to emissions. "Same year OR newer". Some states have specific rules also. You might want to check into where the vehicle will be registered.

I haven't worked on a FWD LS so I was wondering if GM made a special FWD LS block with the old 90 degree bell housing or did they make a 4t80 transmission with the old standard chevy pattern bellhousing? Either way you would most likely need to find a doner Impala with the FWD V8 set up.

After looking at a couple different forums I found this pic of a FWD LS block and as I suspected they made a special block just for FWD that have the same bell housing as the 4t65 and 4t80 transmissions. So a RWD block won't work.

Never mind my above post, I was thinking of a different thread where someone was aking about a V8 swap in a FWD application. As far as you liking the RWD idea on your Impala I would look for a nice 95 or 96 impala and do a LS swap. But hey if you really like the look of the 01 you could probably glue that body to about any frame. I just watched a show where Jay Lenno took a 68 Toranado and made it RWD using a modified corvette frame and he used a LS motor with twin turbos. So with enough time and money anything is possible.

its going to take some fab for the custom interior and most of your trunk is going to be gone once you have the trans and diff in. dont think the plymouth chassis is going to be any good its not going to have the right bolt patterns or engine/trans mounts.

I think the Plymouth frame is the key to making this work. With the wheelbase matching exactly, aside from the impala being slightly wider which will work out for wider back wheels to help with the drivability, the other details are just a matter of fabrication. In fact if my numbers are right I can modify modify some IROC Z mounts. The bottom and fire wall will have to heavily modified as well as some upgrades to the Plymouth chassis. I will have to make fuel and brake lines and most like have to go with a cell in the trunk instead of either gas tank. Still kicking the idea around and gathering information. I'm not gonna start it until I have every duck in a row.

The fbody mounts are just clam shells and its bolted to the cross member right below it. If I were doing this I would just make the engine and trans cross members from round stock, you are going to have to change them anyway the ls is different.they make adapters but they are expensive. And the stock ones take up a lot of room. I don't see much benefits in dealing with the second frame. The stock one is fine if you cut the end of the cv to use in the hub that will be good. For the rear just get a Ford axle, I think they have similar 4.5in stud pattern, or you can use a 10 bolt from a fbody with adapters. You would have to adapt the coils control arms and torque arm but it would be a better handling car. If you put old Plymouth stuff on it it'* not even going to be half as good as the fwd setup on it now. Seems like if you had a fbody that would be a much better parts doner

92 rwd ls1 z34 lumina - All MetalShaping

Z57 Lumina. A good example of someone taking a FWD GM and putting it on a RWD chassis. Looks to be very well documented too, so it may give you some ideas and inspiration.