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Nick that`s where straight cut gear-box, straight cut drop gears & straight cut f/d gears come into play
not only can you change the ratios to make them closer together to suit a lumpy-er cam but also the "straight-cut" part of it all makes for less horse power loss, as there is very little side loads onto the thrusts of all the gears in the process
there are many other things/tricks that can help "loose less" throughout the drive train but mostly all this stuff is for full race applications & as LS1380 has just mentioned--> you can have a "Pig" of a race car on the street if you really want, but it won`t be long before you`re sick of it in the city traffic
That`s why I prefer much bigger capacity engines with much milder cam shafts to creat a lovely torquey smooth & quiet drive-able civilised road car , but at the same time they have heaps of grunt that will (& usually does) beat most of the hotted up race mini engines that seem to be plaguing the streets these days
like i said earlier,,, it`s not so much the Hp we want to see,,, it`s more about the amount of torque & the continued delivery of that torque right the way through the rev range
a big motha train/locomotive may have 500 million Hp & big bags of torque that is well beyond the comprehension of many people,,, but they also weigh 500 million tonnes,,, they`re designed to pull big motha carrages & plenty of them,,, ok so lets have all that grunt but shove it into a mini & then gear it right to suit yeah???
on the other hand -->we could have a Yamaha R6 engine with heaps of revs, not much torque but it screams really fast yeah & has about 130hp,.,, well try to make that engine pull all those train carriages yeah??? Sorry,,, it aint going to happen is it?
it is also going to struggle (Big Time) pulling the weight of a mini ,,, getting it yet???
but it`s got 130hp right???
No real "Grunt" tho
we want "Grunt",,, that`s what we want,,, & if we can make it rev safely & strongly & consistanl;y too (if & when we want it to rev hard) then all the better & then the HP figure will reflect all that grunt with the revs to produce a smooth (not lumpy) easy to drive (Not jerky n jolty) quiet (not loud) fairly economical (not fuely) civilised road mini
Bigger capacity road engines , (Big bores with longer stroke cranks) can be all that & still rev if you want them too & yet have more pull than a bunch of schools boys.
The South Africans actually fitted very large -fat- heavy flywheels into their 1100cc engines to help gain some torque,,, they`re very short stroke engines & like to rev, but have no real pulling power so they fitted the heavy flywheel to maintain some guts for the hills
Think of a pottery wheel people,,, once you get it spinning it doesn`t want to stop in a hurry does it???
the flywheel is what holds the energy,,, lightweight flywheels are great for accelleration but you effectively loose some hill-climbing torque in the process
But if your "Road" engine is already a massive torque monster, then you can afford to drop some flywheel weight & make it accellerate even quicker & can even run taller diff ratios ,,,-->where most race minis use Zippy diff ratios to accellerate & suit/Match the light flywheels & hi-rev peaky cams
it`s all a game of mix-n-match,,, but you have to know your stuff to get the match-up right
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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.
You should put your heart & soul into everything you do.
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