Which Engine?

Originally, I had my heart set on a v8. I blame Mad Max personally! Actually I did consider a bike engined car for some time, as they must surely be the daddy on a track, but ultimately I want a car that I can thrash on track, enjoy on the roads, and also use for the odd weekend away with the missus. A BEC really isn't going to suit all of those demands. (In an ideal world, I'd have one of each of course...I could quite fancy a Silva R1ot as a track blaster...)

So I'd pretty much decided on a v8. When I started researching originally, I concluded that the venerable Rover v8 was the only choice. Small and cheap per BHP. There didn't really seem to be anything else. So I bought the books, did my research...and felt a bit...hmmm. Despite being cheap to buy, you still have to spend quite a lot to get decent power. £3-4500 seems to be fairly ballpark for a 250hp engine. In addition, the power band is very low - running from around 2000-4000rpm. Personally I wanted something a bit more responsive and revvy. No disrespect to v8 owners mind - they are super fast and sound the absolute business...but I think maybe they're not for me after all.

So I started looking again, casting my net a bit wider to include v6 engines as well as v8, looking for something that can produce 250hp (and preferably more) without costing the earth. I didn't want a turbo engine - despite currently owning a turbo car which is great, I do prefer the power delivery of an NA engine. Supercharging has always seemed more appealing to me anyway, despite turbos being ultimately more powerful.

I Spent a vast amount of time reading, asking questions on various forums, and talking to tuning companies. I've summarised my findings and thoughts below; this is all correct to the best of my knowledge, but don't take it as gospel! Costs especially are my own estimates, and you'll find widely varying figures floating around; I've tried to be realistic based on what people have actually spent, rather than what tuning companies say in their marketing. Weights can also be the subject of much debate.

Engine	Weight	Size	Power	Cost	Comments
BMW V8 (various)	?	Width: ~ 750mm	230 hp from 3.5L 394 hp from 4.9L	?	These are no doubt great engines, but their major drawback is their size; being overhead cam, they stick out a lot more than the pushrod type engines such as the rover. One has, apparently, been fitted to a Rush just recently, but by the sound of things, the chassis is quite considerably modified, and bits of it stick out of the sides of the car. The other problem is that there seems to be zero aftermarket tuning for them; so no chance of increasing the power at a later date.
Rover V8	480lb for a 4.0L + ancilliaries	508mm wide 700mm long 650mm high	250hp 300hp	£3000-£4000 £5000-£9000	Small. Fuel economy pretty poor. Cheap for up to 220-230hp,then exponentially more expensive. Low revving, with the power band being below 5000rpm as stock. You do see weights as low as 320lb being quoted, but based on my research, I don't believe these.
Chevvy 350 / 305 V8	530lb	Unknown, but of a similar size to the Rover	320hp and up	£3500 for a crate engine	These old engines produce good power for the money, but are waaay to heavy. And being large-displacement old fashioned designs, are also very thirsty.
Chevvy LS1 V8	497lb	Similar to the Rover	350hp and up	£4500 - £6000	The LS series of engines comes up in every conversation about which engine to choose. Much better in terms of economy and weight than the old chevvy lumps, and still good value for the power you get. But for me, still too heavy, too expensive (gearboxes for these cost another £1800), and a bit too big for a 7. A car that small shouldn't really need 6.2 Litres, surely?
Ford 302 GT40 v8	424 lb	610mm wide 737mm long 699mm high	345hp	£3345 (long engine), say £5000	This would probably fit, though it is getting a little on the long side, and is quite heavy again. Good power for your money, but still rather a lot of money.
Ford Cosworth 24v V6	308lb	670mm wide 600mm long 700mm high	203-230hp stock	Cheapish (I forget exactly what this means!)	The power delivery and rev range seems much the same as the rover, i.e. quite a low revving engine. Quite a lot of tuning available, although I hear some say that it is starting to get hard to find parts. Definately fits (though it's tight) as at least two Rushes are being built with these in right now.
Nissan VQ35DE V6 (from the 350Z)	<300lb	610mm wide 737mm high	200-300hp	Expensive!	Revvy engine, one has recently been fitted to a Rush. A bit on the expensive side though, and hard to tune, from what I've read.
Volkswagen VR6			180hp from 2.9L		A bit too small, and not terribly powerful. Would probably fit well as it is a "staggered inline 6" rather than a true V6, with a single cylinder head. Could not find much aftermarket tuning stuff (seems to be a theme with German manufacturers?)
Alfa Romeo V6	375lb	590 mm wide 560mm long 700mm high	3.0 Engine - 210hp 3.2 Engine - 250hp	Can buy a whole car with a 3.0 in for £300, 3.2 seem to be as rare as hen's teeth...	Look great, sound great. Rev to around 7000, and very oversquare so should be quite responsive. Tuning is available (though not cheap), with increases in capacity to 3.5 or even 3.8L, cams etc. Can also be supercharged to around 300hp using the stock ECU. One has been fitted to a Rush, so it fits. Major drawback is that they are all FWD installations, so will require adapting to fit a RWD gearbox.
Honda "C" series V6 (eg C35A)	?	?	225hp		90 degree bank angle means that this is probably a bit on the wide side. Can find zero aftermarket tuning either.
Honda "J" series V6	?	?	265-300hp		60 degree bank angle so more likely to fit; unfortunately this is a very new engine and seems to be mainly for the US market.
Toyota V6, VZ series (1VZ-FE to 5VZ-FE)	?	?	190-200hp from 3.4L		Designed for high torque at low RPM. Output seems to be no more than a mildly tuned 3.5 RV8 produces, and with a very similar power band, so not much point.
Toyota V6, MZ series (1MZ-FE)	401	?	225hp from 3.3L		Only available from 2003 on, so likely to be expensive still. Doesn't seem to offer much over the Rover, apart from perhaps economy and slightly less weight.
Toyota V8 1UZ-FE	363lb	770mm wide 700mm long 700mm high	265hp	Around £2800, including gearbox	Amazing engines, so smooth that they can be bounced off the rev limiter with a coin balanced on edge on the rocker covers. Bullet proof bottom ends, loads of aftermarket tuning available. Cheap (around £400), though only came with an automatic gearbox - they need an adaptor for a manual and an aftermarket ECU to run without the original gearbox. Very cheap for the power though. Much to my dismay, just too darn big; no doubt could be made to fit like the BMW, but I don't want to compromise the look of the car that much.
Ford Duratec V6 (from the Mondeo ST)	451lb	670mm wide 685mm long 680mm high	200-240		The bare engine is 670mm wide, but the alternator sticks out more than the heads. All alloy, but still rather heavy
Mitsubishi 6G72 (GTO / Shogun 3.0V6)	350lb	585mm wide 500mm long 610mm high	160-220hp	£400-£1000	Very compact, and cheap. The older ones however are not that powerful (sub 200hp). Tuning is limited to turbos or superchargers, and there seems to be a lot of issues surrounding the latter.
Mitsubishi 6A12 V6 (2.0L, from the FTO)		Not sure, but tiny; the 6A series includes the world's smallest production V6	180hp @ 7000rpm		Very compact and revvy. Will fit in a new Colt, so would surely fit in a Rush. FWD so would require adapting to fit a RWD gearbox. No tuning really available, most people seem to swap in a 6G series instead.
Vauxhall ecotec v6 3.0L			180hp - 280hp		Little in the way of aftermarket tuning. I've read that it doesn't take to forced induction very well.
Rover KV6 2.5L	200lb		Can be tuned to around 180hp		A bit on the small side really