TURBO POWERRRRRRRRRRRRRR On a 250?

danejurrous said:
I think what he was referring to was the fact that a super charger will take some horsepower to make some horse power for an example: takes .5 for every 2 it creates. (Not real specs just an example) Where a turbo charger does not rob horsepower from an engine to create horsepower is just uses the exhaust gases rather than a manual link with a pulley or gear where power is lost.

The feasibility of putting one on a bike is not really something I would delve into because if you have the determination to do it you can make anything work. That being said I would probably put my time and money into other areas than a turbo.

That's exactly what I meant - turbos run off exhaust gas as opposed to a blower that needs to be driven off the crank....hence turbos don't take any power away from the crank.

I'm no expert on turbos or blowers but the simple fact that the majority of forced induction applications on bikes nowadays are turbos as opposed to superchargers pretty much speaks for itself.

And yes - that pod filter with the fan in it is a bit of a joke ;)
 
you can get higher fuel rates on the carb just have to re jet for the proper airflow and density. on US carbs your going to most likly remove the plug from idle adjustment and tune from there. get your self a wide band O2 sensor and fuel air meter. Plus as other have said nothing is ever free whwn i t comes to power gains, your always giving up something. be aware of this when it come to how much your motor can handle.
 
twistekeys said:
That sounds RELATIVELY easy compared to charging. So why can't you achieve a higher amount of fuel with a wider jet setup in-carb?

You can. But then you're going to be slower at WOT unless you're burning nitrous. The carbs don't automatically know when you're pushing the "go" button, they only know when the throttle is open.

The most common method of supplying additional fuel at low monetary cost is an in-line fuel pump hooked up to a fuel injector. Use a variable timer circuit to drive a high frequency relay that energizes the injector(s). Press your button for the nos and the injector starts pulsing at the same time. Adjust the pulse width until you get the A/F ratio correct.

It can all be done for under $500 bucks.
 
stevenfrye said:
On the bike Im slowly but surly putting together, i modified the gas cap to seal with a 11 pound spring, and a line (with a one way check valve) fron the airbox surrounding the carbs pressurizing the fuel tank. to keep from going to a rich fuel situation i have a bleed off into a small carbon can with another check valve and line to the vacume manafold.

I'm interested, about uh. What?
 
twistekeys said:
That sounds RELATIVELY easy compared to charging. So why can't you achieve a higher amount of fuel with a wider jet setup in-carb?

Just remember that for every extra LB of fuel you put in, you need an extra 14 lbs (weight) of air. So bigger jets give you more fuel, but how do you stuff the extra air in?

Naturally apsirated has a a limit on the amount of air the motor can move.

The best way to get more power from a 250 is to make it a 350. There is no replacement for displacement.

If you take a small, slow 250 and turbo charge it, you will easily have a slightly faster slow 250.

Not that 250's can't go fast, but fast is relative. It takes HP to go fast, a lot of HP. A 250, blown, injected, NOS'd still will be a 250. Even if you triple the HP, it ain't enough.
 
The easiest, cheapest method of gaining lots more horsepower is a larger capacity motor (or using the same capacity two-stroke to replace a four-stroker!

Anything else is just an excuse to show off your engineering skill (or lack of)!

Crazy
 
Basically what I was trying to say instead of using another fuel pump I'm going to see if I can put pressure on the fuel by way of the boost the turbo is producing and the carbon can set up is going to be used as a vapor catch can and tank pressure release so I don't dump too much fuel into the carbs going from high throttle / high boost to low throttle and the excess pressure bleeds off into the can. I'm working with a kz 550 motor, and just figured out today digging around the motor on the exhaust valves are sets of reed valves that receives fresh air from the intake via case breather and forces air into valve reducing backfiring apparently according to the manual and just so happens to be the perfect place to plumb the compressor blow off too.
 
stevenfrye said:
Basically what I was trying to say instead of using another fuel pump I'm going to see if I can put pressure on the fuel by way of the boost the turbo is producing and the carbon can set up is going to be used as a vapor catch can and tank pressure release so I don't dump too much fuel into the carbs going from high throttle / high boost to low throttle and the excess pressure bleeds off into the can. I'm working with a kz 550 motor, and just figured out today digging around the motor on the exhaust valves are sets of reed valves that receives fresh air from the intake via case breather and forces air into valve reducing backfiring apparently according to the manual and just so happens to be the perfect place to plumb the compressor blow off too.

Those reed valves on the exhaust ports are for emissions reduction. The idea is that the vacuum left after the exhaust pulse draws in clean air and burns up any unburnt gases left in the exhaust. If anything, it increases backfiring / popping rather than reducing it.

And pressurising your tank in lieu of running a fuel pump is not a good idea IMO. You'd be making something that should be quite simple into something overly complicated with more room for failure.
 
stroker crazy said:
Anything else is just an excuse to show off your engineering skill (or lack of)!

Crazy

+1 LOL
The main reason to turbo, it's just easier to connect an exhaust pipe than build a drive, supercharger is more efficient being direct drive, hit the throttle, it goes. The only way to get same effect with turbo, have multiples, small one for low rpm, larger one spools up at higher rpm using pressure from the small one to open bypass valve
Never going to happen,though, if you can't be bothered to do your own research, you will never get around to actually doing the modification
 
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