It`s all about "Designing" the """PACKAGE""" for a certain """POWER-DELIVERY""" of an engine
all these people who go on & on about how a supercharger is better for down-low & a turbo is better for up-top,,, is basically crap ... they either-> don`t know what they`re talking about & have listened to too many others who also don`t know what they`re talking about.... or--> they have simply taken a general rule-of-thumb approach , which can also be quite miss-leading & ill-informed --->(or they`re still living in the 60`s)
A baby turbo like a little CT20-Gt12 will give power almost immediately on a mini engine,,, there`s virtually no lag to speak of & certainly won`t give you a pig to drive, then suddenly a big Hit
alternatively a huge supercharger will work quite well up high in the revs, no problem what-so-ever, with the correctly sized blower with the correct pulley ratio
it`s all "do-able" tho,,,, you """CAN""" have a turbo that works down low & you """CAN""" have a supercharger that works up top. . . . simple as that
But!!!!---> its the power curve, or the delivery of the power that is what were really after... the quality of performance combined with the drive-ability is what makes a nice package
If you want awesome power with a turbo, then yes you would "Up-size" (hybrid) the turbo to suit higher revs to work the higher boost range & yes you will sacrifice low down power & drive-ability
you can have a supercharger set-up with a pulley ratio for big boost down low, but you`ll probably break gearboxes & have almost no usable power in the higher revs
sooooo,,, the trick is to """Design""" the system to work well for your intended purpose---> """""""""As A PACKAGE"""""""
Just simply bunging on a blower, """around-about""" the right-ish size will (if you did it well) work quite well for all round performance & drivability & most probably scare the average Joe/Jane enough to poo their pants & obviously the pub bragging rights are good too, because everyone goes "Wow that car is awesome" & it won`t cost you an arm & a leg
But put it on a race circuit & watch a decent N/A car flog it... unless it`s been """Designed""" well.
Traction & gearbox reliability are both huge issues for minis & it needs to be addressed within the designed "Package",,, hence why the factory did the metro turbos & ERA turbos with slightly larger turbos than optimum, simply to save the gearboxes from being "over-torqued" & busting pre-maturely from the torque produced down low from a "Well-designed" power curve, ... resulting in a bit of a "Hit" in the back when boost finally rises, but they were only soft boosted things from the factory with most of them only having 4 or 5lbs boost,,, add more boost tho & you have a weapon, higher in the revs, because that`s where the turbo map is suited to be working for that engine package
this "design" (for want of a better description) allowed the factory to use minimal mods to the std 1275 engine to obtain a fairly reliable & fairly drivable power unit, but still have some decent poke for the average boy/girl racer
But it`s not "optimum" for power "Delivery",,, it was a """""Compromise""" & thats often what is needed to be done to keep them both drive-able & reliable, (Back in the day)
things have moved on tho since then,,, far better stuff is available now-days
Add a "decent" cyl head (7 or 8 port or twin-cam) to a later designed turbo or supercharger & you have a whole new ball-game... smooth & drivable & heaps of grunt , all the way through the entire rev range (Low & High) whether you turbo or supercharge,,, but yet again i have to say that if you stuff-up the "design" & get a few things wrong which don`t quite suit your intended application & you can easily end up with a pig to drive that fails with breakages
so it`s more about the "Package" ,,, & a better "Package" starts with a better cyl head design & better valve control (Cam-s) ,,, & a later designed charger (whether it be exhaust driven or belt driven)
Anyone can bung a lung onto a dirty old 5-port & make it work ok,,, but to make a really nice power curve that is both drivable & powerful, that also happens to last , comes down to a well thought out & well """""Designed Package"""" ,,, whether it`s turbo-d or supercharged means diddly squat , apart from what it looks like under the bonnet
superchargers don`t give you free power,,, they use engine power to drive them so they`re not the "Best" thing, & they FILL an engine bay quite full,,,, turbos don`t take much power from the engine to drive them, & these days are far better design compared to the old ones, so they spool up far quicker with very little lag (if any) when designed to suit your own intended "Package", but do tend to create more under-bonnet heat (compared to a super-charger)
However, & yet again, these days we have had the benefit of years & years of research & development thrown into the "forced-induction" swimming pool & under-bonnet heat can easily be reduced to a minimum causing almost no issues what-so-ever,,,, & add to the fact that the ability (through simple design) to have a far cooler inlet charge (more simply) via the use of a decent intercooler (Air or water) makes for far greater power efficiency, so you really can have your cake & eat it with a turbo these days
There is a Garrett turbo package available to suit "Any-ones" needs/wishes & as long as the """WHOLE power-unit PACKAGE""" is designed & sorted well,,, before the engine lands in the engine-bay,,, then you`re going to have a wonderful drive-able smooth torque-y engine that will deliver the power """"the way YOU want it"""" --> low or high , or all the way through the rev range
this can also be done with a super-charger
either way, they`re both do-able & will both work very well, provided it`s "Designed" well to suit your intended application
not everyone wants a super-charged, overly-full, complicated engine bay
not everyone wants to spend the amount of money needed to have a well sorted turbo donk either
but to just "generalize" about one being better than the other is just stoopid & simply shows a lack of knowledge/experience,,,, """"Especially""" when we`re talking such small engines as ours & with such a plethora of later, well designed, forced-inductions systems now avaliable
don`t get me wrong,,, i`m not sick of hearing it all the time,,, but i must admit, i am sick of hearing it all the time
super-charge or turbo charge,,, do whatever you want,,, heck you can do both if you want & have massive power the entire way through the entire rev range, if you wanted & if you were willing to throw enough money at it to do so
Just be ready to repair/replace gearboxes, whether you supercharge or turbo charge ,,, if you have more than 160hp on tap,,, you`ll be repairing/replacing gearboxes at some stage,,, either way
so it really dont matter which one you have, provided you`ve set it up ("Designed") the """"PACKAGE"""" to suit your intended purpose/application.
end rant
