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Supercharged or turboed dirtbike

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And you would do this because???????.........

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And you would do this because???????.........

Because YOU CAN!

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And you would do this because???????.........

 

I was going to say,

 

"OBVIOUSLY!!!!....!!!! because hes a KIWI" but i see your from NZ too....

personally

I HATE TURBOCHARGERS

they make a motor feel like mushy responseless doody

In other words, motors feel shitty when turbocharged because their response is dicatated by throttle position, load, rpm

while naturally aspirated engines and supercharged engines response is dictated by throttle position and rpm..

 

now i have thought of a supercharged 250.

but how do you drive the supercharger? from the camshaft sprocket?

the cam chain is not strong enough, it will weight as much as a 450, and for the same power used more fuel.  The heat it would generate would be nuts too.

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Because YOU CAN!

 

From a Kiwi perspecive......I get that.....because that just the sort of thing we do but really.........Just buy a 450 or a 500......hell why not go all out and build a 700. To do it well on a turbo I think you will need injection. It's been done for sure. I would love to see you do it!!!!!

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I HATE TURBOCHARGERS

they make a motor feel like mushy responseless doody

In other words, motors feel shitty when turbocharged because their response is dicatated by throttle position, load, rpm

while naturally aspirated engines and supercharged engines response is dictated by throttle position and rpm.

 

I'm surprised that this is still such a common misconception...

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I HATE TURBOCHARGERS

they make a motor feel like mushy responseless doody

In other words, motors feel shitty when turbocharged because their response is dicatated by throttle position, load, rpm

while naturally aspirated engines and supercharged engines response is dictated by throttle position and rpm..

What's you experience with turbos? This sounds like a response from someone that drove a 1989 Turbo Probe and nothing current.

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I'm surprised that this is still such a common misconception...

 

without variable geometry, or an exhaust valve, header, and turbocharger destroying anti lag system they do not respond the same way as an equal horsepower (likely larger) NA motor, or a supercharged engine.

I haven't driven a ton of stuff, but,

im a dirt track racer i ran a 9200rpm 280hp ford 2.3/2.5 pinto engine in a mustang i demolished the championship with 8 outa 10 races, and I prefer instant throttle response and use it to loosen a slightly tight car.  Steer with the rear >:]

 

I drove my x girlfriends subaru wrx sti, which was a nasty understering thing, the engines response was not fast enough to use it to correct the push useless and boring for me to drive.

 

i drove a 680hp ford gt (the new gt40 not a mustang gt)

thas a 5.4L with a twin screw supercharger this specific one with a smaller than stock blower pulley and some dyno tuning

>:]  I had NO PROBLEM LOOSENING THE CAR WITH THE THROTTLE NO PROBLEM AT ALL >:] :] :]

 

my next "road race car" will be a 2.8L ford 4 cylinder with an esslinger midget head and a whipple twin screw shooting for 500hp.

Edited by EnglertRacing

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A properly sized turbo will have no lag

 

a properly sized turbocharger for a 2.5L driving around town at 300hp can be properly sized and spool quickly but not instantly but what happens when you need one properly sized for 1000hp?

hows that drive on the bottom?

takes no time to spool?

doubt that.

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maybe i havent driven the latest turbo technology, but i do know what it is, and i think personally i would enjoy a twin screw with an intercooler and or water injection over a turbocharger any day.  the turbocharger takes less power to drive yes i said it a turbo does cost some power that it more than makes up for, but nothing like a supercharger the supercharger takes some serious power to turn.. im not sure about normal applications but a blown alcohol dragster... it takes 700hp to turn the blower!!! O.o

 

so psi for psi the turbocharger will make more power.

but the twin screw is full boost at any time.... a beautiful thing. a torque curve like ... nothing else... more fun.

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I guess I took it as NA engine vs same size turbo engine. You can do a LOT of improvements on drivability adding a turbo. Yes, it's a lot harder when comparing a big NA engine to a tiny turbo engine with only a peak power number as a goal. But if throttle response is the only goal here then forget all this and go get a CR500 all ported up and have the crank and flywheel turned down as light as possible. 

 

 

I have to ask - How streetable would that Pinto engine be? I'm guessing you better stay up on cam or suffer the consequences. That's there a turbo really shines. You could build the engine with a much more low-end friendly cam & porting, but still get the same peak power by compression some air into it. End up with a much wider powerband. 

 

Also, the STI is known for trading tip in and turbo lag to get bigger power and WOT performance numbers. Many prefer the std WRX for "real world" driving due to this.  The latest generation has been getting quite a bit of that in reviews. 

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I guess I took it as NA engine vs same size turbo engine. You can do a LOT of improvements on drivability adding a turbo. Yes, it's a lot harder when comparing a big NA engine to a tiny turbo engine with only a peak power number as a goal. But if throttle response is the only goal here then forget all this and go get a CR500 all ported up and have the crank and flywheel turned down as light as possible. 

 

 

I have to ask - How streetable would that Pinto engine be? I'm guessing you better stay up on cam or suffer the consequences. That's there a turbo really shines. You could build the engine with a much more low-end friendly cam & porting, but still get the same peak power by compression some air into it. End up with a much wider powerband. 

 

Also, the STI is known for trading tip in and turbo lag to get bigger power and WOT performance numbers. Many prefer the std WRX for "real world" driving due to this.  The latest generation has been getting quite a bit of that in reviews. 

The US cars cut a lot of corners to meet their target price. The sti's in the rest of the world have about the same or less lag than a wrx and more power than the US sti's. It's really about how much money and technology you want to put into it. You can build a high power turbo engine with little to no lag, it's just going to be an expensive high strung machine like everything else in the off road world. I'm just not sure how ceramic compressors would hold up in off road conditions. 

Also, with the turbo, you can build an engine for low end power, and use the turbo to make up for the top end, pretty much making it like two motors in one. Practical for dirtbikes? Probably not due to packaging issues, is that a reason not to try? Not one bit, maybe you'll find the next big step. 

Never stop experimenting and trying new things. 

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Im currently debating on building a purpose built snow bike using a turbo motor.. Sure as hell won't be a 450. Looking at a raptor 700 engine for e start, reverse and reliable power.

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Any of you seen this? I'd rock one for sure, great way to add a bit of puch to a supermoto!

 

 

edit: heres a link to their kit

 

http://www.mpfab.com/product/mpfab-stg2-turbo-kit-yamaha-wr250xr/

 

disregarding my preference for the method compressing the intake charge.....

that just cant be as reliable as a 450.

these things are built light light light to be N/A screamers

i dont know how long they would last

theres a 100hp turbo kit for crf450s that supposedly dont blow up the bike.!

but there meant to really make up for power loss at altitude on snow bikes and then some.

 

i could just imagine the rod bearing doesn't appreciate this much.

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I guess I took it as NA engine vs same size turbo engine. You can do a LOT of improvements on drivability adding a turbo. Yes, it's a lot harder when comparing a big NA engine to a tiny turbo engine with only a peak power number as a goal. But if throttle response is the only goal here then forget all this and go get a CR500 all ported up and have the crank and flywheel turned down as light as possible. 

 

 

I have to ask - How streetable would that Pinto engine be? I'm guessing you better stay up on cam or suffer the consequences. That's there a turbo really shines. You could build the engine with a much more low-end friendly cam & porting, but still get the same peak power by compression some air into it. End up with a much wider powerband. 

 

Also, the STI is known for trading tip in and turbo lag to get bigger power and WOT performance numbers. Many prefer the std WRX for "real world" driving due to this.  The latest generation has been getting quite a bit of that in reviews. 

 

the twin screw pinto motor will be an animal. off idle response with a twin screw is just nuts.  Its positive displacement like a roots. but the clearance of the rotors decreases making it a positive displacement compressor vs just a pump like a roots. so its much more efficient less power for the same pressure, lower discharge temperature.  Ill build the next one so that it would make about 350N/A minus the fact that its 8-1cr and put 20+psi to it... no intercooler just a dual fuel system with methanol coming in on a second set of injectors.

 

the 2.5l i have that has been collecting dust since i raced last in 2011 wouldn't be much fun. it doesn't run below 6000rpm thanks to a .650" 280 @ .05" cam with 106 lobe separation. that won't be very friendly, but it would be great to blow the doors off some v8s and show some ricers what an iron ford 4 can do it would probably attract a lot of attention and cause trouble :)

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