Hey, I too am looking at building a performance driven hybrid.
If you look at the work involved in the base of the installation, it's not too different from how a lot (dare I say most) of people are swapping Tesla/Bolt/Leaf cradles/subframes into the rear of their cars. Read around here and look at youtube. So many people putting them in the rear. But from what I've seen, you're not going to find a lot of support for hybrid stuff anywhere on the internet.
Seriously consider starting with a gokart/golf cart hybrid first (with regen). I did, and it's fun as F!!! But if you can't finish the smaller challenge, you can't fathom how difficult the larger challenge will be.
Pros and Cons to your integra idea (basically. my sameidea)
- ICE up front + electric in back = Decoupled AWD (RWD power without sacrificing FWD power)
- Possibly better gas mileage.
- Definitely faster.
- You only need like 4-8ah battery. I think Infiniti's fast hybrids use like 1.4kwh batteries... Which means you only need like 100 or 200 LPA cells.
- Unseen complications? (throttle regen braking, etc)
- Your car doesn't have AWD already. So you can't use the existing knuckles.
- Honda ICE Transmission
As for AWD parts...
sells AWD parts for other Honda/Acuras models (civics, preludes, etc). But all of their parts are custom made.... So if their knuckle breaks or the hub becomes too loose to hold a bearing - AND they quit making that part... Then you're back to fabricating your own parts. (this is where a CRV or civic with interchangeable CRV parts would be convenient). I don't know if the CRV knuckles are interchangeable for Integras.
Another problem you'll run into is the Honda's transmission (for your FWD ICE motor). Honda's automatic transmissions are weak. But automatic would be the most ideal for this setup. Why? B/c what happens if your electric motor continues to accelerate while you leave your manual transmission red lining in gear? Unfathomable RPMs (not in a good way LOL)! The electric transmission has the potential propel your car and simply blow your ICE up. So you'd have to come up with a system/throttle shutoff that watches the pulses of your ICE rpm.
So... Automatic transmission would be way more friendly. But... Hondas autos don't like power (from the ICE). So modding the ICE would be tricky.
Here's a video of a Pontiac Fiero hybrid build. He actually does the opposite of what you'd be doing. B/c the Fiero ICE is in the rear of the car.
Handful of MR RWD swapped Leaf/Bolt/Tesla videos on youtube. Not many hybrid builds though
RWD Leaf build:
Also a ton of videos of Hybrid golf carts, a lot of people have evidently started there lol.
Personally, I'm thinking of picking up a Leaf subframe. From what I understand, the Bolt likes to have all the Bolt parts there. And Teslas have some limitations too (like you can only use a Tesla pedal).
I'm in Texas (USA). You're free to hit me up if you want. Just send a PM.