diesel vs petrol power

So how do you weigh the usefulness of torque against that of HP when making a decision between two engines?
Don't really bother. The torque difference between a diesel and a petrol, once the typical differences in weight and gearing are taking in to account, are not all that important for out and out performance. Typical diesel torque can probably make up for a.. 5% difference in power.
 
Hang on Robbie, are you saying that people are going to the trouble of transplanting expensive HDI engines into old 205's? why? why would you go to the expense and complications of installing a modern diesel engine into an old car when it would be far easier, and you would get better performance by transplanting the MI or even GTI6 lump, not to mention it would be cheaper.

Farm workers used to do this all the time, basically you get near enough 205 1.9gti performance after the screw mod (yo) with 50mpg but most importantly they could run them on the farms red diesel on the side for almost free motoring. Kinda makes scene then but not really anymore.

Someone should shoehorn this in to a 205.

Worlds most powerful and efficient diesel

At maximum economy the engine exceeds 50% thermal efficiency. That is, more than 50% of the energy in the fuel in converted to motion.
For comparison, most automotive and small aircraft engines have BSFC figures in the 0.40-0.60 lbs/hp/hr range and 25-30% thermal efficiency range.
 
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"Epic Torque" helps make overtaking safer. I can just press and go, while you're faffing around trying to find the correct gear.

I guess that means that either diesels have the sloppiest, most inaccurate gearchanges in the world, or diesel drivers are unable to use a manual transmission with any proficiency.

Dropping a gear or two takes what, about 1/2 second, maybe a second at a push?

FWIW you don't make overtaking safer for the poor buggers behind you, chocking them with a cloud of black smoke. :(
 
Good. It's a cracking car with a cracking engine. Proof that certain engines suit certain cars. Diesels are detuned at the factory to meet emissions standards so all your doing is spending money to claim back power at the expense of economy and the environment ;) You don't need more power in the 182 anyway.

Thats exactly it, certain engines suit certain cars and certain people.

I've driven a 1.5 oil burning Clio and it was OK but didnt feel "right". Whereas my Mondeo - big car that is most at home on the motorway. Plenty of relatively effortless mid range grunt and motorway cruising at sub 2000 rpm - it just works. Of course the mondeo can also make a good B road blaster with the ST220 and the derv would be rubbish at that - but thats not what I want/need out of a car.

There seems to be a lot of people here who have the view that all diesels are rubbish, without exception. This is of course complete crap, its just that they dont suit everyone - just like petrol engines dont suit everyone. You only need to look at the amount of diesels being sold to see that.

As for the 205 HDi conversion - I reckon its been done just because they can. A lof of people like doing things like that, just to see what would happen!
 
yes but to get a genuine 200+bhp out of a gti 6 would be very expensive.

look on cliosport .net 182's are rarely getting over 200 bhp even with throttle bodies. you cant just stick cams in and chuck a set of bodies on a standard gti-6 lump, it will last about 5 minutes, the bottom end wont take the thrash

I already posted on page 3 that you can get 200bhp on TBs easily enough with the PT81 cams.

The bottom end wont go bang, so stop talking wind, its fine even when supercharged.
 
Is the GTI-6 weaker than the Mi16? My friends tarmac rally car is putting out just under 270bhp on a stock Mi16 crank and block with the limiter set to ~8500RPM.
 
Is the GTI-6 weaker than the Mi16? My friends tarmac rally car is putting out just under 270bhp on a stock Mi16 crank and block with the limiter set to ~8500RPM.

People expect about 250bhp on a low boost supercharger application with a standard block, anything higher you want forged rods/pistons.

As for N/A tuning, I cant recall off the top of my head anyone with a very highly tuned N/A due to the expense of it.
 
"Epic Torque" helps make overtaking safer. I can just press and go, while you're faffing around trying to find the correct gear.
If your driving is so poor that changing gear makes overtaking dangerous, you shouldn't really be overtaking in the first place.
 
LOL @ faffing around trying to find the correct gear.

You mean making 1 gear change (if even needed)... how do we cope.
 
People expect about 250bhp on a low boost supercharger application with a standard block, anything higher you want forged rods/pistons.

As for N/A tuning, I cant recall off the top of my head anyone with a very highly tuned N/A due to the expense of it.

This is a normaly aspirated engine. A very expensive one.
 
This is a normaly aspirated engine. A very expensive one.

I can imagine, just saying that I cant think of anyone whose really tried with a GTI-6 lump as its just easier to supercharge it.

Plus most people just go insane with shiny parts for the handling/brakes rather than increasing the power.
 
Apologies. I get annoyed when people don't read a post properly.

A Focus RS would destroy a 182, so what's your point?

Enlighten me to your point here, the 182 and Focus RS are two completely different cars. Maybe you should compare it to say the Megane R26.R and see who destroys who? Anyhoo diesel, it has its merits and works quite well in my Sprinter on a daily basis. However a diesel "hot hatch" just doesnt work, least of all in a 205. It may be quick but its not what the 205 is about, hooning around great roads through the revs and listening to the engine sing. I have to lol at the Golf GTI comparison, given you (stinka) spent time in a dealership you could have chosen somthing better to argue against with your knowledge that the MK4 GTI was abit (understatement) slow and an insult to the GTI badge. On a side note I quite like the Fabia vRS but they aint quite they bullets some people make them out to be, either that or my car is a super car in disguise!
 
Enlighten me to your point here, the 182 and Focus RS are two completely different cars.

My point is a Fabia vRS is completely different to a Clio 182, yet another forum member was making a similarly mis-matched comparison.

Maybe you should compare it to say the Megane R26.R and see who destroys who? Anyhoo diesel, it has its merits and works quite well in my Sprinter on a daily basis. However a diesel "hot hatch" just doesnt work, least of all in a 205. It may be quick but its not what the 205 is about, hooning around great roads through the revs and listening to the engine sing. I have to lol at the Golf GTI comparison, given you (stinka) spent time in a dealership you could have chosen somthing better to argue against with your knowledge that the MK4 GTI was abit (understatement) slow and an insult to the GTI badge. On a side note I quite like the Fabia vRS but they aint quite they bullets some people make them out to be, either that or my car is a super car in disguise!

I'd like to make a point - the GT in GTI stands for Grand Touring. The Golf and 205 GTI being the original hot hatches. Drive to the shops like your pants are on fire down a fun B-road with a big grin on your face, then drop the back seats and stick a chest of drawers in the back and drive home. ie the best of both worlds. You want ultimate B-road hoonage then buy an R26R, but it's not a hot hatch due to the scaffolding where the folding back seats should be. It's a much use as an Elise for carrying furniture. Some of the hot hatches I wouldn't consider going grand touring in, whereas I'd happily do so in a Golf GTi or my Fabia.

I've never said the vRS is a bullet/supercar in disguise. I enjoy it for what it is and it suits me perfectly. The vRS is a good value, cheap to run hot hatch that happens to be diesel. Revs ain't everything to everyone.

It does seem to be attracting some of the same devotion as the 306 DTurbo, I suspect to due cheaper insurance. I also happened to own said 306 in the 90s before the kids started screw modding them.

What VW sold in the UK as the Mk4 Golf 2.0 GTI was a cynical badge engineering exercise. Peek in the boot and the original data sticker states it is a Highline. The proper GTi was the 1.8T. Proper seats, sports suspension and a decent engine.
 
Maybe this post in another forum will help a few understand the relationship between torque, power and performance:

Clicky

I read that over a year ago but found it very handy.
 
You want ultimate B-road hoonage then buy an R26R, but it's not a hot hatch due to the scaffolding where the folding back seats should be. It's a much use as an Elise for carrying furniture. Some of the hot hatches I wouldn't consider going grand touring in, whereas I'd happily do so in a Golf GTi or my Fabia.

I've never said the vRS is a bullet/supercar in disguise. I enjoy it for what it is and it suits me perfectly. The vRS is a good value, cheap to run hot hatch that happens to be diesel. Revs ain't everything to everyone.

What VW sold in the UK as the Mk4 Golf 2.0 GTI was a cynical badge engineering exercise. Peek in the boot and the original data sticker states it is a Highline. The proper GTi was the 1.8T. Proper seats, sports suspension and a decent engine.

Anyone who buys a R26.R for daily use in my mind is bonkers, somthing special for the weekend and track use. As you point out its completely impractiacal for anything else. On the subject of the Golf GTI again, the 2.0 was poor and the 1.8t 150 was just as much of a insult. Thankfully VW managed to correct themselves for the MK5 and even the 180 was more like it. Im not bashing the Fabia vRS and im aware you didnt say it was a bullet but between people telling me and reading around there are numerous owners who believe they are just that. In the grand scheme of things its a warm hatch, its very good at what it does but put it with some proper hot hatches (Cooper S, Focus ST, Civic Type-R etc) and its not quite there. Much like my Megane, sits in no mans land not quite sure what its supposed to be. Ideal area tbh, its what makes them good value.
 
Yesterday I drove from B'ham to York and back, 300 miles I guess, cruise control set at 70mph for vast majority of the journey.

My 325D returned 56mpg, aircon off, just me sat in it, no luggage or anything.

Then, after getting home and having some nosh, I went out to Stratford for a hoon with my brother and we bothered some country lanes. Touched 3 figures regularly, had an absolute hoot. Got home and economy average had dropped to 50mpg. City driving it returns 33mpg versus the 21mpg my old 330ci gave.

3.0 litre, 6 cyl, 200bhp, it's far from slow - at a rough guess I'd say straight line speed would match a 200bhp CTR without any trouble (which weighs I guess 150 kilos or so less). Now here's the really funny bit - it actually sounds fantastic when you boot it - 6 cylinder growl and inside the car you hear zero clatter.

There are some superb performance diesels on the market but some people seem to be in denial about it.
 
Yesterday I drove from B'ham to York and back, 300 miles I guess, cruise control set at 70mph for vast majority of the journey.

My 325D returned 56mpg, aircon off, just me sat in it, no luggage or anything.

Then, after getting home and having some nosh, I went out to Stratford for a hoon with my brother and we bothered some country lanes. Touched 3 figures regularly, had an absolute hoot. Got home and economy average had dropped to 50mpg. City driving it returns 33mpg versus the 21mpg my old 330ci gave.

3.0 litre, 6 cyl, 200bhp, it's far from slow - at a rough guess I'd say straight line speed would match a 200bhp CTR without any trouble (which weighs I guess 150 kilos or so less). Now here's the really funny bit - it actually sounds fantastic when you boot it - 6 cylinder growl and inside the car you hear zero clatter.

There are some superb performance diesels on the market but some people seem to be in denial about it.

Out of interest, what sort of difference did you find there was in price between your car and the equivalent petrol model when you bought it?

So many people around here seem to think theres a huge price difference which doesnt make it justifiable for anyone and I just dont believe thats true these days, especially with mpg figures like that
 
Out of interest, what sort of difference did you find there was in price between your car and the equivalent petrol model when you bought it?

So many people around here seem to think theres a huge price difference which doesnt make it justifiable for anyone and I just dont believe thats true these days, especially with mpg figures like that

£1200 difference.

That'll get paid back in economy but the biggest payback will be the lower depreciation on the derv model. At the end of 3 years our figures showed the derv losing less money than the petrol.
 
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