Diesel Power?????
Discussion
Ok stupid question time ...
If you had a 357 bhp petrol with 330 torque
and a 290 bhp diesel with 430 torque
put them in identical sports cars which would out perform which and in what ways
eg at santa pod or on a track day ...
is something like a 3.5l BMW oilburner not an option for engine swaps ...
feels so wrong to be suggesting such a thing ... any thaughts?
If you had a 357 bhp petrol with 330 torque
and a 290 bhp diesel with 430 torque
put them in identical sports cars which would out perform which and in what ways
eg at santa pod or on a track day ...
is something like a 3.5l BMW oilburner not an option for engine swaps ...
feels so wrong to be suggesting such a thing ... any thaughts?
Diesels tend not to rev very high which is why they have good torque but low HP. HP is just a mathematical calculation of torque and RPM (simplified). They have a very narrow power band which is why a while back when they first became common in cars that model had 6 gears compared to its petrol cousins 5.
Cruising on the motorway is the natural habitat. Track days I have my doubts as they will take a lot of effort to ring the performance out.
Steve
Cruising on the motorway is the natural habitat. Track days I have my doubts as they will take a lot of effort to ring the performance out.
Steve
Hmm - I looked up the vid that made me think of this - twas Topgear review of BMW 535 diesel
www.youtube.com/watch?v=__HpspsvRVg
Made me wonder what it would do in a cerbera - one thing I hadnt realised is weight dissadvantage of
diesel lump ...
(goner be burnt as a witch soon ...)
DAS
www.youtube.com/watch?v=__HpspsvRVg
Made me wonder what it would do in a cerbera - one thing I hadnt realised is weight dissadvantage of
diesel lump ...
(goner be burnt as a witch soon ...)
DAS
question is ... is there any merit in a daily driver TVR to having a performance diesel
(cant believe Im suggesting such a thing)
Everybody assumes its best to go for a yank lump but all that torq from a diesel???
My only experience of a diesel is a clapped out transit and a scenic I hired on holiday ...
The scenic drove really well - lazy I suppose pulled really well in any gear ...
A cerbera sounds pretty rattly anyway!! (when cold) but some of the Bigger diesels dont sound that bad?
I assume its easier to get a BMW deisel thru emmissions than it would be an AJP cerb engine...
Fuel economy would be better ...
You could run it on chip fat as well!!
Wish I had started this thread under an alias now ...
(hopefully wont need to consider and engine transport for a while anyway (touches wood quick!))
TTFN DAS
(cant believe Im suggesting such a thing)
Everybody assumes its best to go for a yank lump but all that torq from a diesel???
My only experience of a diesel is a clapped out transit and a scenic I hired on holiday ...
The scenic drove really well - lazy I suppose pulled really well in any gear ...
A cerbera sounds pretty rattly anyway!! (when cold) but some of the Bigger diesels dont sound that bad?
I assume its easier to get a BMW deisel thru emmissions than it would be an AJP cerb engine...
Fuel economy would be better ...
You could run it on chip fat as well!!
Wish I had started this thread under an alias now ...
(hopefully wont need to consider and engine transport for a while anyway (touches wood quick!))
TTFN DAS
I think the problem would be the mass of the engine. A big part of chassis design is the distribution of mass - the biggest of which is the engine followed by the transmission. Diesels are (generally speaking) iron blocks and heads with everything inside being that bit more dense than on a petrol - all in order to contain the less well formed and controlled explosions.
This means that 'just' dropping in an engine screws up the dynamic characteristics of the vehicle and needs a completly new suspension setup to try and compensate for this.
Ignoring this problem though, it depends on the gearing and torque curve.
I did just write a very long thing about gearing with same max power, but different RPM and torque but it was very waffly and I lost the plot after a bit, so here's a visual aid:
www.howstuffworks.com/fpte5.htm
What it fails to mention is that with a lower mass car and less torque to transfer the gearbox can be a lot lighter and geared so that the wheels turn a lot slower for the engine speed, allowing you to use the power for longer without changing gear. It also blurs the disticntion between engine torque with wheel torque (with the reduction gears). There's a good article on the web I'll try to find...
This means that 'just' dropping in an engine screws up the dynamic characteristics of the vehicle and needs a completly new suspension setup to try and compensate for this.
Ignoring this problem though, it depends on the gearing and torque curve.
I did just write a very long thing about gearing with same max power, but different RPM and torque but it was very waffly and I lost the plot after a bit, so here's a visual aid:
www.howstuffworks.com/fpte5.htm
What it fails to mention is that with a lower mass car and less torque to transfer the gearbox can be a lot lighter and geared so that the wheels turn a lot slower for the engine speed, allowing you to use the power for longer without changing gear. It also blurs the disticntion between engine torque with wheel torque (with the reduction gears). There's a good article on the web I'll try to find...
Edited by MTV Dave on Monday 12th February 22:11
Ive got a 200bhp'ish mk4 golf gti (tdi) anniversary. Its very quick and gets you into trouble without realising it as you get up to speed so quickly and have to hammer the anchors. It is fun to drive, but for me will never compete with a petrol performance engine! But as the everyday runaround, its quick and still give 40+mpg!
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