Sure, V-4 engines are used in motorcycles, but look at how much LESS weight they have to move. It may be a good choice if you're building a cust= om bike, or perhaps even a trike, but not a car. In addition, yes, there are q= uite a few odd-ball motors out there. Unimogs will sometimes have I-5 cylinder motors in both flavors of petrol (err, gasoline) and diesel, and even GM ma= kes V-18 diesel motors. But just because they're made, doesn't mean that you'd = want to use them. Hence why they are used for only custom/specific applications. Which is why you typicly don't find them in passenger automobiles. The Audi engines do indeed to be quite interesting, but still not a good ch= oice IMO. 90° V-6 @ 3 litres? You're back where you started with the PRV, but no= w you've got less support. Aside from that, for alomst the same price that yo= u would pay for just simply the engine itself & ECUs, you could have one of DMCH's HiPo Conversions. On a side note, the Audi motor does not appear to be a PRV cousin. Too bad IMO, as it would have been very facinating to convert the B288F, or a Z7X-715 over to a DOHC set up. Another motor is the Rover V-8 (used by Bob Brandys in his car). A small block V8 that appears to fit rather well into the D's engine compartment ma= kes it a rather nice choice! But I haven't really been able to pull that much i= nfo up on the motor stateside over here (although I've not searched that intensly = to be fair). In the UK, it seems to be quite a popular motor, but Stateside, I= 've only found info on the Pontiac 215 from back in the early 60's. Perhaps Bob, or = someone else could provide a bit more info on resources related to this mot= or. As far as Japanese engines go, that would be a no there too. VTEC itself is= quite an interesting feature, but is useless for street driving since you h= ave to damn near red-line the engine to activate it. Otherwise, it's just a market= ing ploy. It's the same as back in the 60's when Detroit was measuring BHP of i= t's engines @ the flywheel, with no accessories attached. That isn't a fair measurement because after all, no one drives around with no accessories attached. And it's the same with VTEC, because no one drives around town constantly @ 6K+ RPMs. But, I'm not here to debate marques. Simply put, the= majority of Japanese engines are efficient, and some powerful, but way too = complicated in both engineering, and installation. VTEC is great for trying= to balance economy, and extra output from a motor, but, our goal here is power= first, economy and emissions 2nd. And the effort and cost involved to insta= ll either a 4 banger, or a V6 into a DeLorean just isn't worth it. This become= s less like a conversion, and more like a "kustomization". It's being done no= t so much because it's more efficient or powerful, but simply because it *can* b= e done. Now on the flip side of this, the Wankel Rotary is indeed an engine that wo= uld be a good canidate. It's compact, lightweight and damn powerful. It also ha= s a long history of engineering behind it. The new Renesis motor by Mazda is indeed a bit low on the torque end, but hey, it's the first version out in = how many years? And no matter what it is, you never, ever want to buy the first= version of anything. Even car reviews have complained about the torque problem too. If rotary is something you want, then give it a couple of year= s, and see what improvements they make. But be warned, rotary engines are NOT cheap at all! Moreso if you don't have a core motor to exchange when trying to buy one from what I've seen. But others can really give you more = info on this conversion process than I can. Which brings us to the American engines. Now I'm not a "bowtie" person, so = I've no idea as to the specifics on either the Vortec, or the Grand Nationa= l motors (I must be odd man out here, because I'm from Ford family, versus most DeLorean owners who seem to be GM people). But, I can tell you that since they are both popular/common motors, and the since the Vortec is used= in so many various applications, that they will have MANY aftermarket options, as well as a great deal of resources of both parts and data suppor= ting them. So that, coupled with a few people that have actually completed DeLorean-specific conversions related to these motors really makes them a good choice. But in the end, if you're looking to "think outside of the box", and want t= o have a powerful motor in your DeLorean that others consider unconventional, the = choice is easy. Matter of fact, it's staring you right in the face. The PRV= ! You already know it fits, and it keeps with the cars heritage quite nicely! :) = In addition, it has a LONG history, and a large support base behind it (albeit= not in this country). Applications for the motor have included everything from = commuter cars, to even F1 racing. Some forms of it's dress also include dua= l turbos that pump out 450BHP. Although you'd never need anything quite that = powerful for the DeLorean. So if you're looking for a challenge of some sort, consider that the gauntl= et that has been thrown down! After researching things quite a bit, it was the= road that I chose when it came to souping up my car. Once the remainder of = my restoration is completed, it is the next project that I'll be begining o= n. And believe me, converting over to a dual turbo with EFI shouldn't be a problem= at all. It may have a couple of hurdles and challenges, but it is indeed feasa= ble. -Robert vin 6585 "X"