Whats the best way of getting torque? I would prefer torque rather than bhp and i'm guessing the cam profile will determin when the power comes
in.
I'll be building my engine soon and would like a torquey engine with the power coming in at about 1500 rpm which is where i'm estimating
i'll be using the power most.
Is this for the mini? A series or something more modern? If A series, what sort of use will it see? Ie, do you want a high eving screamer, or a slower slogger?
Look at a rally cam rather than a race cam if you want low down pull rather than high rev power. Higher compression ratios are good. A longer stroke rather than a fatter bore is better too.
When it comes to torque the more cc's the better IMHO.... torques a direct result of the force of the combustion pushing the piston down the
cylinder, the greater the piston area, the more force you get to turn the engine i.e. torque. Small engines i.e bike engines 
lack torque as they
are of a small capacity.
Hence why V8s have ludicrous torque figures, but not necessarily high BHP as they dont rev very high.
High CR is also a good way to get torque, hence why deisels have very high torque figures.
David
[Edited on 2/10/06 by flak monkey]
Yes it's for a Mini. I would like it to produce as much torque/power as poss low down for pulling away rather than screaming it's nuts off
at 6000 rpm.
It will be for the street, not the track.
ta
What size is the engine? Is it A or A+, or is it an old cooper engine? Either way, a nice overbore and a crank re-grind to something like 1430cc will give a nice torque figure. If the engine is to keep a standard bore/stroke, then head work and as said a rally rather than race cam. Also, what options do you have as per induction?
It will probably be a 1330 and it's an MG Metro A+ motor. Induction is via an SU HIF 44 and a big bore zorst will sort the smelly stuff! Not sure what to do about the head, depends on cost.
More torque Big flywheel perhaps.
Steve.
One way to get big torque from an A series, may be (once you've overbored it) is to supercharge it.
Might start making things expensive and complicated, but a s/c from a BMW mini might be just the ticket, and reasonably cheap.
ATB
Simon
Go to WHSmiths and have a peek in this mag http://www.gr8website2.com/calverst/main.htm
One of the example engine specs is for a largish (well it is a mini engine ) torque engine (it's the 1360cc uses 73mm pistons rather than the
normal 73.5mm 1380 overbore).
[Edited on 2/10/06 by iank]
Treat yourself to David Vizards book Tuning the A series . Tells you everything you need to know and more .
I read in a magazine (can't remember which) about an A series that had been fitted with a BMW bike cylinder head.
Seemed simple-ish and the power figures were impressive..
The mini engine with bike head was in the PPC.
If you want more torque use a diesel engine. There are some mighty fine turbo diesel engines out there and I have seen a Westfooled with an Isuzu
1.5td from a Corsa.
Mates directly to a gearbox from some other RWD Isuzu badged car.
And I've just upped the boost on mine and its gone from a standard 66bhp to 95 with masses more torque. 130mph here we come!!
Psst, dont tell anyone but the new Mini has a turbo engine instead of supercharger. I've seen them in the repair area at Cowley. SHHH!!
Steve
[Edited on 2/10/06 by coozer]
Fit a 4.33:1 final drive. Voila, more torque at the wheels for the same bhp 
The Kent 266 cam is excellent for a road going mini, perfect idle and pulls like a train from low RPM.
quote:
Treat yourself to David Vizards book Tuning the A series . Tells you everything you need to know and more .
quote:
Originally posted by flak monkey
When it comes to torque the more cc's the better IMHO.... Small engines i.e bike engines
David
There's loads of threads regarding this old chestnut that will dispell this myth. Just do a search. Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
They have a higher compression ratio = higher torque. Bike engine tuning merely means that it happens high up in the rev range. You could fit a
different cam and have it lower down but you'd lose the power, but if you want your torque low down...
I was waiting for you to comment. Perhaps i should have put 
after it 
Lets face it bike engines are totally different to car engines. If they hit their rev limit at 6500rpm they would be pathetic and useless. But seeing
as they will easily rev to well over 11000rpm they do still have very good power outputs since power is related to rpm and torque combined as we all
know...
David
[Edited on 2/10/06 by flak monkey]
quote:
Originally posted by coozer
The mini engine with bike head was in the PPC.
Steve
[Edited on 2/10/06 by coozer]
quote:
Originally posted by Hellfire
quote:
Originally posted by flak monkey
When it comes to torque the more cc's the better IMHO.... Small engines i.e bike engines
David
Oh dear, oh dear.
Phil
The first thing to do is to buy the Vizard book. It's the tuning bible for the A series.
If possible I'd bin the single HIF44 and get something better. Whilst I know the HIF's are good, I'd prefer a twin carb or single
webber set up (IMHO). If you want something a little different, a single downdraft IDA webber (as fitted to GT40's!!!) works really well! My
engine has a single 48 IDA webber, with lots of mods, and has 150/160bhp and a mere 1338cc! They are available in smaller sizes too. Also, the cam
choice will play a huge part in how the engine produces its power. I'm also a huge fan of the VP3C cam, which forms just a part of the APT range
of cams. These are all high lift, low(er) duration cams and are actually suited to the A series, as opposed to the higher duration/older cams which
are less good. for example, the VP3C in a 1400cc engine can produced 110lbft and 130 bhp. This cam also has a tame, if slightly lumpy idle and pulls
from low down too.
Also, Cooper rods and other bits aren't that expensive, but as with every thing it depends upon bugdet. Stroking a standard crank will mean using
the Cooper rods though, due to the now smaller journal diameter. Head work and camming will do wonders for the A series, and if money is tight, can be
done yourself and still produce very reasonable results.
[Edited on 2/10/06 by DIY Si]
quote:
Originally posted by smart51
Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
They have a higher compression ratio = higher torque. Bike engine tuning merely means that it happens high up in the rev range. You could fit a different cam and have it lower down but you'd lose the power, but if you want your torque low down...
PS in answer to the original question, one previous answer hit the nail on the head, stick a supercharger on it.
The A series (or A+) head will never breathe particularly well, but the supercharger will get neatly round that one and can be "pulleyed"
suitably to make enough torque to blow your head gasket at whatever revs you care to choose.
PS surely you want an HIF6 carb not HIF44?? (not that I know much about these things but that's what I used on a 1275 in my mini days!)
HIF44 is the metric version of the HIF6
The BMW bike cylinder head conversion featured in PPC is now available from Morspeed. http://www.morspeed.co.uk/latest-newspage.htm
quote:
Originally posted by smart51
Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
They have a higher compression ratio = higher torque. Bike engine tuning merely means that it happens high up in the rev range. You could fit a different cam and have it lower down but you'd lose the power, but if you want your torque low down...
>
quote:
Originally posted by smart51
Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
They have a higher compression ratio = higher torque. Bike engine tuning merely means that it happens high up in the rev range. You could fit a different cam and have it lower down but you'd lose the power, but if you want your torque low down...
If you want to have loads of bottom end go for a low overlap cam with plenty of lift (as much as you can get within the confines of your springing and
standard rocker ratio).
And also smaller valves/ports will give you better low speed torque - because you are increasing the gas velocity in the port for a given engine
speed.
quote:
My vauxhall XE 16v,
1998cc 231 Nm 204bhp
ahh but that has one of those horrid whooshy things attached to it! Can't argue with the numbers though!
quote:
Originally posted by NS Dev
ahh but that has one of those horrid whooshy things attached to it!
quote:
Originally posted by DaveFJ
quote:
Originally posted by smart51
Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
They have a higher compression ratio = higher torque. Bike engine tuning merely means that it happens high up in the rev range. You could fit a different cam and have it lower down but you'd lose the power, but if you want your torque low down...
My Fiat tin top..... 2470cc 230Nm
which is 93Nm for each 1000cc. sorry, not good enough
arggh you keep pulling me in on this one...........!! LOL XE = 115Nm/1000cc
quote:
Originally posted by NS Dev
Higher compression ratio = higher torque.............
errrrr NO!
WRONG!
quote:
Originally posted by smart51
Yamaha R1 998cc 108 Nm
Citroen TU 954cc 74Nm
Toyota K1-3fe 998cc 93Nm
Honda fireblade 998cc 114Nm
Bike engines have less torque?
quote:
Originally posted by NS Dev
you can have all the compression in the world and make no torque at all, look at a diesel engine at tickover!!!
quote:
Not in terms of nm/cc, but who on earth puts a 1 liter car engine in their locost? Far, far more realistic to compare a bike and car engine with simmilar power outputs....
This is a real minefield.
Good example of how figures can be totaly blown out of proportion.
Circa 1893 Large static steam engine, I meter diam main cylinder, triple exspansion sysytem.
Almost 680lbs/ ft of torque, 90 bhp and all this at about 60 revs / min.
wouldn't look good in a locost though
too true!
There are a wole number of ways in which to generate motive power, steam engines CAN be a very effective way of doing it!
If current levels of piston internal combustion engine development were applied to steam engines who knows where we would be now??
I was always musing over the possibility of using waste heat on an internal combustion engine that operated at high temperature to operate a secondary
condensing steam turbine co-coupled to the internal conbustion engine output.............................but that's a whole different story!
Its a B@*st*rd replacing the dilithium crystals though
quote:
Originally posted by Johnmor
Almost 680lbs/ ft of torque, 90 bhp and all this at about 60 revs / min.
quote:
Originally posted by MikeRJ
quote:
Originally posted by Johnmor
Almost 680lbs/ ft of torque, 90 bhp and all this at about 60 revs / min.
Ahem.
60*680/5252 = 7.7bhp
what about the anglia MAE engine ?
wasnt that over 100 bhp from 997cc, with the obvious downdraft ports etc .
Steam? hows about this ?
Linky
I think 145 mph and 300Bhp is qute acceptable from a steam car.... whats interesting is the land speed record for a steam car in 1906.... 128mph!!!
I may be wrong ( i often am )
But i think fromula applies to Internal combustion engines.
Henry Robinson's formula (*) —
Area of ram x stroke x pressure
33,000
This was used in steam engines in the late 19th centuary.
James Watt defined the horsepower as 33,000 ft lbs per minute.
This alllows steam engines to be calculated without using the revs per minut as they of produce their maximum torque just before the stop moving.
IE Max torque at 0 rev/min.
as i say I may be wrong
they have then the best filling grade...
Tks
quote:
Originally posted by stevec
More torque Big flywheel perhaps.
Steve.
quote:
Originally posted by smart51
Citroen TU 954cc 74Nm
quote:
Originally posted by DaveFJ
I think 145 mph and 300Bhp is qute acceptable from a steam car.... whats interesting is the land speed record for a steam car in 1906.... 128mph!!!
the link in my post is to the new record attempt site.....
quote:
Originally posted by Johnmor
I may be wrong ( i often am )
But i think fromula applies to Internal combustion engines.
Henry Robinson's formula (*) —
Area of ram x stroke x pressure
33,000
This was used in steam engines in the late 19th centuary.
James Watt defined the horsepower as 33,000 ft lbs per minute.
This alllows steam engines to be calculated without using the revs per minut as they of produce their maximum torque just before the stop moving.
IE Max torque at 0 rev/min.
as i say I may be wrong
My ZT - 410nm at 4000rpm
ATB
Simon
If HP is defined as RPM X torque/ 5252 then:
1 HP += the ability to move 33000lb ,1ft in one minute (James Watt, looking at dray horses)
Some of the largest static engines ever made were produced to roll 18" battleship armour plate.
( they made three in Glasgow and lost one in transit)
They could compress and roll a 16ftx24ft red hot piece of steel 18" thick.
The rev of the engine never exceeded 50-60 rpm.
So, if perhaps guessing they had a torque of 2000lbs/ft . that means they developed
2000X55/5252 20.9hp
20.9 don't seem much
That seems to be the same as a 125cc 2 stroke. I,ve seen these static engines and boy, they look more impressive than a 125.
I guess ts all down to interpritation of power.
That's correct. Big old engines produce minimal hp, but loads of torque. A mates 1940's tractor puts out 24 bhp (on a good day!), but can
easily pull tress up!
Oh, how the hell do you lose a rolling mill THAT big?!
The Wartsila-Sulzer RTA96-C turbocharged two-stroke marine diesel engine makes 5,608,312 LB Ft of torque and 108,920 BHP at 102 RPM from 25,480
litres. Its thermal efficiency can excede 50% so fuel consumprion is only 1660 gallons per hour.
5608312*108920/25480 = 23973
http://people.bath.ac.uk/ccsshb/12cyl/
quote:
so fuel consumprion is only 1660 gallons per hour.
5 million ft/lbs. !!!!!
Thats almost galactic proportions, 2300ft/tons of torque.
Thats got to froth the water at the back end.
quote:
Originally posted by Johnmor
If HP is defined as RPM X torque/ 5252 then:
1 HP += the ability to move 33000lb ,1ft in one minute (James Watt, looking at dray horses)
Some of the largest static engines ever made were produced to roll 18" battleship armour plate.
( they made three in Glasgow and lost one in transit)
They could compress and roll a 16ftx24ft red hot piece of steel 18" thick.
The rev of the engine never exceeded 50-60 rpm.
So, if perhaps guessing they had a torque of 2000lbs/ft . that means they developed
2000X55/5252 20.9hp
20.9 don't seem much
That seems to be the same as a 125cc 2 stroke. I,ve seen these static engines and boy, they look more impressive than a 125.
I guess ts all down to interpritation of power.