Advice on Frankenstein Car

Hey,

So I have a 2005 Nissan Altima SE-R in a 6MT. (Only 3076 of those ever made). However, the engine completely exploded and caught fire. As I tore everything apart on it, I found out that the previous owner before me jerryrigged a 1997 Chrysler LHS motor into it, and used parts from all types of models - from a tensioner pulley that was off of a 1996 Mazda that had a rotary engine, to a 2007 Subaru Rubicon throttlebody, to a 2014 Corolla Air Fuel Sensor, to a 2002 Acura (something) passenger motor mount, to a transmission from an unknown year Subaru WRX STI (the 10-bolt universal one).

The engine took out my cooling system and lines entirely, radiator/support, fuel lines/injectors, and a lot more. Since I cannot find an LHS of even that same generation, and I don't know how the previous owner rigged it all together, how would you go about this? Would you go with a commonly used engine and go with adapters/modding? Or just custom build the engine and go from there? As a background, I am a technician. PFA.

Hard to say because, as you say, it's a massive butcher job at this point - TBH, I'm surprised you didn't pick up on that before buying the car, but...

Unless you REALLY want to keep the car, it may be more cost-effective to simply sell it all as-is - but if I were in your position, I'd try and find out exactly what's been changed, and see what my options were to bring it back to stock, or drop in an RB.

And yes, I REALLY want to keep this car... It's as close to my dream car as I will get. And well, that's where the funny part comes in. He put the 1st gen VQ35DE engine cover over top to cover it up... Plus I don't often look at branding or part numbers on serpentine tensioner pulleys or motor mounts or air/fuel sensor when I am buying a used car, lol. But that's the complete list in the original post. I contacted buddy after I found his Kijiji account (like eBay or Marketplace), and he said yeah, he combined a lot of crap, and it was all because of a derailed plan of converting it to RWD/AWD with a 2012 Pathfinder motor, lol. So he had to improvise. All that I listed in the post is all that was rigged inside the car, except for wiring obviously. I do have 2 harnesses lined up now (body/engine), but I still am uncertain. Because an RB26 would cost me over 100k for the engine alone where I am at, and if things were stock, a 2nd or 3rd gen VQ35DE is a direct bolt in, minus a little bit of cam adjustment which I have the proper kit for. But with all the changes, idk how that would work, or if I would need adapter plates from the engine to the WRX STI 6 speed trans, or etc.

And as a reference, it is somewhat easily possible to do awd/rwd to my SE-R. There is a space in the back for a rear axle instead of knuckle hubs, the Murano rear subframe bolts right up to the Altima, 90% of the Altima suspension works with the remainder parts being from Murano or 350Z/G35, there is a space that is almost hollow enough for a driveshaft underneath but has room to be enlarged, and the 350Z hubs and differentials bolt right up, and can ride normal height with some minor modding. The only figuring out would be the engine. Either 350Z/370Z/G35/G37 engine, Pathfinder/Frontier/Xterra Engine in a swap, LS swap (has been done and I know the guy), RB26DETT or RB25 swap (100k RB26 or 48k RB25 used, and both for sale half way across the country in Toronto), or just try and undo everything he did, especially since he don't remember how he did everything since he did it in 2014... I do have a spare stock transmission (F51 SE-R) that can be repaired and used if need be for whatever option I use. I am just unsure what to do, because there is no simple solution to this, as you know... lol

Ah, sorry, my mistake - I was thinking it was a RWD car. Going back to "stock" based running gear may be the wisest route, all things considered. There are many other options for the running gear, though, even if a NISSAN based choice "may" assist with the installation.

Yeah. I guess in all this, I am not expecting to have someone here just tell me the whole transformation solution or that X, Y or Z is the easiest option. More so if I should just try and transplant an engine into it like a commonly universally swapped engine (LS, 2JZ, RB26 if transforming - or a 2nd gen or 3rd gen VQ35DE with HR cams (My car originally came with the 1st gen VQ35DE). Or if I should just build a customized block through a manufacturer/bore and hone/etc to where I can make everything fit to that. Mind you a lot of things besides the engine need replaced now, so that's why I was asking all of these. I don't wanna just go 1 route, spend thousands, switch up, thousands more, and end up spending tripling more than I needed to get it done.

Have you thought about deferring it for a bit, and keeping an eye out for a crash damaged similar version of the car, preferably rear-ended?

That should be a source of all the odd bits and pieces, as well as the major components like intact wiringharness(es), engine, transmission, etc.

I have actively been looking. There are no 2002-2006 3.5 Altima's, Maxima's or Quest's for sale, let alone part out or scrap near my area (400km radius). They are all 2007+, which they changed up the VQ35DE starting then, and are a separate generation. The closest engine to me was a 2004 Maxima engine 390,xxx miles across the Canada/US border from me in Boston, Massachusetts. (I'm in Canada). So I just fear a $1450 engine plus shipping, border duties and customs, and 15% purchase tax we have here where I live would make it too much, but idk that total yet. Plus that mileage.