www.zxrworld.co.uk

yeh altho ppl seem 2 think that superchargers are soooo much better, they are but only just because they draw power from the engine 2 use them wer as turbo's dont!

GEM.... u wana teach ur wife to keep her scooby in the turbo range for optimum acceleration, if u go out of the turbo range (rev 2 high) then u loose power, and the turbo has 2 rewind itself wen u change gear! weras if she changed at about 4000rpm then the next gear the turbo will b spinning fast still nd hold lots of boost 2 continue with....also does ur scooby have a recirculating dump valve or a standard 1 or a crappy 1 that just makes the swoosh sound?

How Forced Induction Work
http://www.lextreme.com/Turbo.htm
dean

dunno what sort of dump valve it has, have worked out that red lining in each gear is a no go cos as u say the turbo runs out of steam and puts u back to sq one

gem

zxr_maniac wrote:yeh altho ppl seem 2 think that superchargers are soooo much better, they are but only just because they draw power from the engine 2 use them wer as turbo's dont!

GEM.... u wana teach ur wife to keep her scooby in the turbo range for optimum acceleration, if u go out of the turbo range (rev 2 high) then u loose power, and the turbo has 2 rewind itself wen u change gear! weras if she changed at about 4000rpm then the next gear the turbo will b spinning fast still nd hold lots of boost 2 continue with....also does ur scooby have a recirculating dump valve or a standard 1 or a crappy 1 that just makes the swoosh sound?

what a load of bull, you cant just pluck the 4000rrpm figure out teh sky without knowing the cars output(torque/bhp) and its gearing ratios.

zxr_maniac wrote:if im correct i do believe, that a turbo takes exhaust gases which turns the turbine which then pushes air into the engine, this works in wats called a turbo range ( usually 2500rpm to about 3500-4000rpm ). and a supercharger works immediatly because it draws energy of the engine 2 push more air into the engine, but work immediatly as soon as u switch the engine on 2 the moment u switch it off. please correct me im rong

again, its not as simple as that. you cant say all turbo cars have a "range", its entirely dependant one the car its fitted and the spec of the turbo itself.

eg, i had a t25 (garrett) on my 220 turbo, this would achieve full boost (12psi i had it set at) by 2700rpm and it would hold till about 5500rpm where it started to drop off to about 10-11psi. this was due to the turbo being a little small for the application.

i then fitted a t28 (again garrett) which came form a nissan pulsar gtir. this was a much bigger turbo, capable or flowing 1.5 times as much as the t25 (around 300bhp as apposed to t25's 200ish bhp), the downside to fitting a bigger turbo is increased lag as it takes longer for the exhaust gasses to spool the turbo up to speed. this menat full boost(14psi) didnt come in till about 3500rpm with this fitted to my car but when it did achieve fulll boost, sh1t me was it quick, it also held solid to the redline.

thats a quick basic explanation, if you want more, let me know.

i think this pic explains how a turbo works perfectly

i wasnt plucking 4000rpm outta the sky, on average most cars, a standard car! each gear dops the revs by about 1000rpm-ish! so if he starts 2 get boost at 3000rpm then gd time 2 change will b ABOUT 4000rpm.

and ALL turbo cars do have a "range" else the wud b called superchargers! its because the take a lil while 2 wind up which is y u dnt have an immediate boost of power. its quite hard 2 explain but thats y sum cars...twin turbos have a small 1 and a little 1, the small 1 winds at lower revs which winds the big 1 faster so u have more boost from the big 1

zxr_maniac wrote:i wasnt plucking 4000rpm outta the sky, on average most cars, a standard car! each gear dops the revs by about 1000rpm-ish! so if he starts 2 get boost at 3000rpm then gd time 2 change will b ABOUT 4000rpm.

and ALL turbo cars do have a "range" else the wud b called superchargers! its because the take a lil while 2 wind up which is y u dnt have an immediate boost of power. its quite hard 2 explain but thats y sum cars...twin turbos have a small 1 and a little 1, the small 1 winds at lower revs which winds the big 1 faster so u have more boost from the big 1

its not about dropping gears back to the revs that it starts making boost. its about keeping the revs in the power band (area where PEAK torque is made), and not every car makes its peak torque at the same point.

and re twin turbos, do abit more research then come back.

i may not know too much about zxr400's/bikes YET but turbo engines are something ive spent the last year fixing/working on/researching and learning about so i suggest you get your facts straight before you start

ill leave it at that unless you want more info?

zxr_maniac wrote: GEM.... u wana teach ur wife to keep her scooby in the turbo range for optimum acceleration, if u go out of the turbo range (rev 2 high) then u loose power, and the turbo has 2 rewind itself wen u change gear!

pmsl, you really have no idea do you???? the highe rthe revs the faster the turbo spools.

please, dear lord save us

interesting read, and I don't mean the DEI system.

Northern ANdy wrote:interesting read, and I don't mean the DEI system.

aimed at anyone in particular?

both turbos and superchargers force fresh air into the engine (more air needs more fuel = more power). A super charger is powered by a belt run off the crank whereas a turbo uses exhaust gases to spin a turbine which is connected directly to another turbine which pumps air in. The two different turbines are contained within the same casing most of the time but they both deal with different gases.
Generally superchargers take power to make it and give power from idle right up to redline whereas turbo chargers are tuned to specific input gas volumes, therefore they have a very definate powerband, usually in the top half of the rev range.
Big turbo chargers = big power BUT also BIG lag
small turbo chargers = small power and small/no lag

carsounds_dan wrote:both turbos and superchargers force fresh air into the engine (more air needs more fuel = more power). A super charger is powered by a belt run off the crank whereas a turbo uses exhaust gases to spin a turbine which is connected directly to another turbine which pumps air in. The two different turbines are contained within the same casing most of the time but they both deal with different gases.
Generally superchargers take power to make it and give power from idle right up to redline whereas turbo chargers are tuned to specific input gas volumes, therefore they have a very definate powerband, usually in the top half of the rev range.
Big turbo chargers = big power BUT also BIG lag
small turbo chargers = small power and small/no lag

at least someone has some sense

lets just say I know how both systems work, as do some of us, while others do not.
Turbo's also sap power slightly because gas flow rate out of the exhaust falls, so you also lose some scavenge aswel. Sadly both systems heat the air due to compression, (in the case of the turbo some heat transfers through from the exhaust vanes to the inlet side) and so th air must be re cooled to give max possible volumetric efficiency. yeah baby.,

Northern ANdy wrote:lets just say I know how both systems work, as do some of us, while others do not.
Turbo's also sap power slightly because gas flow rate out of the exhaust falls, so you also lose some scavenge aswel. Sadly both systems heat the air due to compression, (in the case of the turbo some heat transfers through from the exhaust vanes to the inlet side) and so th air must be re cooled to give max possible volumetric efficiency. yeah baby.,

Hence intercoolers being desirable on higher performance turbo engines? (EDIT: Come to think of it, do any supercharged setups use intercoolers or other cooling methods? )

I seriously hope you've all managed to get a look at the linked thread yet? The very first reply to the original post nearly made me spit my Krupnik out!

Apparently the man behind the DEI is also 39 - not 5 as I first suspected!