Most economical way to 250bhp?

[heathrobinson]

Idle question time - while thinking about a replacement for my xr4x4 24v (still not really a fan of it's looks) I started thinking about the dreaded economy.
The 2.9 24v v6 in the 4x4 sierra gives me about 30mpg if I'm sensible, which is to say never, and 20mpg when thrashed as it deserves to be.
I've been considering something like a Granada as it's replacement, so are there any engines that'd do better than 20mpg on a swift mooch around?
Pinto, Saab or Volvo turbos? J lumps? I rather like torque, and I do a lot of autobahn driving, so 90mph for long stretches.
I know this is a proper can of worms, and that there's probably no definitive answer, but hey ho!

So, what's the most economical way to 250bhp+ then? Go!

[adam73bgt]

Saab 9-3 Aero HOT, 205bhp as standard but an £80 remap takes it to 250bhp and its not too hard to get to 270 from there



Also does 30mpg day to day happy as anything, the economics of mine have been slightly offset by the fact it needed a timing chain, clutch and the bulkhead welding though...

[misterbob]

Economical? As in fuel economy?

I'd say a modern VAG group 2.0T engine.
265 BHP out of the box and 35-40MPG

[claymore]

Volvo T5, my T-5R with a few cheap tweaks will give you an easy 275bhp and manage over 30mpg on a run, I average around 25mpg on a daily basis.

[sparkyt]

I'd say tdi any. vag derv can get you good hp and great economy to go with it

[composimmonite]

Think about cost of fuel rather than actual economy and budget for an LPG conversion. LPG at under 70p litre and unleaded at 115p then running costs will be proportional lower.
So something that does, say, 15mpg on LPG will be cheaper to run than 20mpg on unleaded.
Makes a Chrysler 300 Hemi viable ?

[adam73bgt]

Ultimately I think the answer will be some form of 4 cylinder turbo as in the real world they're just the best combo of economy and power.

The only issue I have with them (my Saab included) is that I find them really dull! the exhaust note does nothing for me :/ So something like a Volvo 5 pot or some other engine with a bit of character that could also deliver 250bhp and 30mpg would be the clear winner in my eyes

[Dez]

id probably go for chipped/manual pumped bmw M51 (2.5TDS) diesel with a bigger intercooler and turbo. can be found in e36 or e34, choice of saloon or wagon in each.

correct wheel drive, strong gearboxes, good handling car with a bit of luxury thrown in. some of the german ones are producing silly HP on manual pump conversions. all the torques because diesel.

they don't do huge economy for a diesel, 30-35mpg, but then you don't have to run it on full price pump fuel either.

[heathrobinson]

^ like your thinking there Dez. Hadn't really thought about diseasles, but that's probably the easiest way to torquey power with reasonable economy. Are that generation of beemers all canbus nasties, or could I get the engine and box to work in something else? I also like the sound of a manual pump - I don't really trust anything you can't turn up with a screwdriver!
Should have said that at the start - has to be RWD, and capable of being transplanted into something like a mk2 Granada, so not too many electrical horrors.

As you say compo, lpg is always a good option. I had it on my v8 Landy, but then there's always the option of putting it on something that does 30mpg, and getting really good mileage per pound! However, all the extra gear puts me off a bit, and there's not many stations out in the odd corners where I spend a fair bit of my time. Still might put it on my capri, with a blos carb or two.
I've a number of ideas I'd like to play with to increase economy, as addendums as it were, like lpg on a diesel, but some of them are a bit weird, so I'll save that until I have something a bit more concrete to waffle about.

[Mystery Machine]

With those criteria, I'd be buying a £1k LS400 on LPG (you can get a good one for that)

But then that's probably because I'm really feeling the need for wafty luxury these days.

[MrSpeedy]

Mercedes W124 with the OM606 3.0 dizzle. Tweaked fuel pump and bigger turbo and you're over 250 easily.

The more modern OM613 cdi is 197bhp in standard form and easily chipped to 250, but if you're looking for an engine donor the common rail would be a problem

[Paul Y]

LSx Based Chevy small block.

The LM7 truck motor has 300hp out of the box and about the same, if not more in torque. Team it with a manual gearbox and our 'Merican cousins are quoting 25-28mpg.

Upgrade to an LS3 cam and springs for an extra 75-90hp.

Or bolt on a $900 turbo kit for upto 700hp, 600 is safe for longevity. Have a look at Sloppymechanics.com for more cheap fun.

If it a car you want then try a 4th gen Camaro. Cheap to buy, cheaply made ( the interiors are awful) and cheap to make monster power. They are fairly good on fuel 20-22mpg if you take it steady probably 0 if you don't....

Sod the economy....POWWWWWWWAAAAAAAHHHHHHHH......


I may have had a beer...

P.

[igor]

Have you considered the fuel economy difference between a four cylinder that's screaming its heart out at the speed limit and a big old dinosaur six or V8 that is barely fast idling at cruising speed? I was getting 18-20 mpg from a '79 Toyota Cressida with the 18R 2 litre four and a consistent 22 mpg from a '78 Ford Falcon 4.1 litre six.
As others have suggested LPG is a good option. I ran my TK Bedford that got 10 mpg on LPG almost all the time and found it to be much more cost effective than petrol.

[DavidB]

As said, Saab B204 is good. I bought a 1999 Saab 9-3 SE with tax and MOT for £390, and then put the engine in my Astra, and sold the Viggen wheels and bits off the Saab for £400, and then weighed the Saab shell in for £120, the profit covered the ECU remap and tea/biscuits for my garage (nom nom). I didn't want to break the Saab, but the interior STANK.

[bobman]

Cummins, Duramax, powerstroke, IMO diesels shouldn't come in 2liters that's for milk! haha Duramax 4x4 sierra do it!

[craig1010cc]

I picked up my sab 95 areo 250 bhp for undr £600 AND I'm averaging 29.4 mpg and that is mixed A road bladting and crawling around bristol. On a motorway slog, mid 30s is easily achievable

[Dez]

May 20, 2015 19:20:48 GMT heathrobinson said:

^ like your thinking there Dez. Hadn't really thought about diseasles, but that's probably the easiest way to torquey power with reasonable economy. Are that generation of beemers all canbus nasties, or could I get the engine and box to work in something else? I also like the sound of a manual pump - I don't really trust anything you can't turn up with a screwdriver!
Should have said that at the start - has to be RWD, and capable of being transplanted into something like a mk2 Granada, so not too many electrical horrors.

As you say compo, lpg is always a good option. I had it on my v8 Landy, but then there's always the option of putting it on something that does 30mpg, and getting really good mileage per pound! However, all the extra gear puts me off a bit, and there's not many stations out in the odd corners where I spend a fair bit of my time. Still might put it on my capri, with a blos carb or two.
I've a number of ideas I'd like to play with to increase economy, as addendums as it were, like lpg on a diesel, but some of them are a bit weird, so I'll save that until I have something a bit more concrete to waffle about.

i think its about 14 wires to have it running outside the donor AND have all the gauges working as long as its pre-96 or so. you can make it run with less than half a dozen. they're pretty self-contained in terms of engine loom and ECU. ive got all the info and wiring diagrams at the workshop. or, you can just convert to the old style fully manual boost referenced pump with a little machining, as they're still a variant of the bosch VE pump.

i think someone on here was sticking one in a granada, and someone else was putting one in a jag.. ive got one i was gunna put in an e30 but i sold the e30 and am saving the motor setup for something else.

[surprisingskoda]

I know it rules it out being common-rail, but economical and 250bhp isn't far away from normal now with modern diesels, and with the likes of a late-model BMW E46 330d putting out 204bhp standard and 280+ with nothing more than a remap, and still seeing over 40mpg, even up to high 50s depending on driving... 250bhp is only limited by what you want to fit, space-wise, budget- or fuel type- limited.

[Deleted]

theres some vag diesels (common rail) in the later t5's etc that are 175 as standard. People have mapped them up and over 250.


Alot of people will say the earlier VAG diesels are good for 250bhp as well, But the 1z etc isnt very strong in the bottom end, People have had 250, But not for long.

It seems 160 is reliable and torquey with a cheapy vag engine.

[heathrobinson]

Yeah, the m57 Beemer lump is rwd, and can go well over 250 without bother, but the injectors seem to be a service part, and you'll need 6 at about £190 a pop...
The turbo seems to be limited in lifespan too, and a high-mileage lump that'll probably need all that doing fairly soon is still nearly a grand.
The m51 and om606 seem like the best bets from the oil burners, and the Lexus lump isn't a bad shout, they're pretty plug'n'play for good numbers, and on LPG are pretty thrifty too.

I really, really love the character of the cosworth 24v, but it costs so much to fettle and to get anything more than 240ish from. If it weren't for that, I'd go for another of those and LPG. Given the amount I seem to be spending to build up the one for my Capri, I just keep thinking that there has to be another route to a fast, fairly economical "sensible" car for day to day stuff.