turbo vmax 600.

coryv4

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This is a pic of mocking up an exhaust flange.on the flange in the picture there is now a rectangle mount on the end to bolt that cup to the turbo.

2012-05-25_10-45-41_824.jpg
 

A couple of bucks said:
How fat will you start out on jetting?
im probably going to have to jet down the way this is set up it pressurizes the float bowls as the boost goes up and will have a greater fuel charge. on my banshee i had too leean out almost 5 jet sizes and it was still a tad rich.
 
If everthing is right, you would ADD about 100 to your MJ, or add a 100MJ power jet system to the carb.

If your that rich, your blowing past your needle and seat, or have the wrong needle and seat (stock gravity feed)
 
toydoc said:
If everthing is right, you would ADD about 100 to your MJ, or add a 100MJ power jet system to the carb.

If your that rich, your blowing past your needle and seat, or have the wrong needle and seat (stock gravity feed)

this is not my first rodeo with turbo 2 stroke the way i have these set up the boost increase the fuel charge and pick up this method has been test on many machines including my turbo banshee. when i first put the banshee together i had to jet down so much that i would probably melt a piston if i even thought about going wot without the turbo or any less then 15lbs of boost and that is with alky wich is alot more sensitive to change.
 
I'm good with what ever you want to do (or don't do). It was just a FYI. Don't want people read it and think if they add a turbo, it will make fuel so jet way down on your first run. The question was asked how fat sould you start on jetting when you add a turbo. The correct answer is jet up 100~120 to start.

Also alky is not sensitive at all with BSFC (more is better). It does likes timing and spark energy, but most people don't / can't set them up and they think it's the fuel
 
i did not mean to come off as a dick or a smart *** i was in a hurry and kinda stressed. by no means do i want anyone to do what i am doing with out an idea of what forcing air into the motor does and how it stresses rods rings and bearings and also the possibility of detonation or an extreme lean condition. the setup i have is a "pitot plenum" i made a test run on the jack stand with the turbo not hooked up and it was slightly rich note that i did drop the main quite a bit along with the needle because its 80 degrees out. i dont have the number of the jets i put in id have to take the carbs apart again the plugs were a little wet. with the turbo on it ran fine until it started building boost then it just loaded up with fuel. pulled the plugs and they were black. the reason i have it jetted for this weather is so i can get alot of testing and improvment done before winter comes along i still have alot of fabing to do to make it not look like a cobbled mess. i am also tinking about rigging up an intercooler off a z1 turbo to see if i notice any gains or losses. i still have a good 6 or 7 months before any snow so it gives me a good window to set it up properly. ive heard from from a guy that he ran 9lbs for 10k miles on this sled. hae you guys seen anyone else run higher boost on this motor with good reliability?
 
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also the turbo i am using is a gt25 a/r .80 i am not a big fan of variable vain turbos such as aerochargers ive seen a couple 2 strokes blow because of the turbo vains sticking open and one broke a compressor shaft because the vain stuck and overboosted at lower rpm.
 
No problem, very cool the stuff your willing to try and do.. so keep it up.

It sounds like (without seeing it) you have unequal pressure in the carbs. Make sure all float bowl vent tubes are ran and sealed to your air inlet box. Add a tube over the slide of the carb also. The carbs have to feel the same pressure all the way around it, not just in the bell mouth. The I use a "pop off" checker to make sure the needle and seat hold pressure i'm looking for (18~20 lb)

The air to air cooler only really helps if your making run after run. First run even without a intercooler rocks. So get everything set then go after a cooler.

The pistons had updates on the 600's. I use forged pistons. Not sure if 10K on turbo is normal, but they seem to hold up fine.

I've never seen a aerochager blow anything up. People blow things up. The aerochager just stops spining when the shaft / bearing goes out. It cant push or suck parts in the motor
 
Also some of the ATV guys maybe installing the aerochargers worng and causing them to burn the shaft / bearings out. Aerochargers are oil bath with a wick. They have to sit upright. If you turn them like other turbos, you can run them dry
 
toydoc said:
No problem, very cool the stuff your willing to try and do.. so keep it up.

It sounds like (without seeing it) you have unequal pressure in the carbs. Make sure all float bowl vent tubes are ran and sealed to your air inlet box. Add a tube over the slide of the carb also. The carbs have to feel the same pressure all the way around it, not just in the bell mouth. The I use a "pop off" checker to make sure the needle and seat hold pressure i'm looking for (18~20 lb)

The air to air cooler only really helps if your making run after run. First run even without a intercooler rocks. So get everything set then go after a cooler.

The pistons had updates on the 600's. I use forged pistons. Not sure if 10K on turbo is normal, but they seem to hold up fine.

I've never seen a aerochager blow anything up. People blow things up. The aerochager just stops spining when the shaft / bearing goes out. It cant push or suck parts in the motor

would an inter cooler be helpful this is a sled that i take on trips across the U.P with hardly any rest time and also hitting up drifts. i didnt want to run an intercooler on my banshee because i would only makes 2 300 foot passes then kill it for cool down.
 
also the turbo has a oil resi that is about 1/4 of a quart in size plus an oil cooler and a coil of line so the turbo all in all takes about a half of quart of oil. i am also thinking about tapping into my antifreeze return line because the turbo ihas water jackets. would this be enough to keep the turbo in operating order for long periods of run time i have no experience with atv/snowmos that run a turbo longer than a few minutes. only short runs.
 
For trail i'd skip the intercooler for now. It really helped me with back to back 660 runs. Didn't do anything I could feel in the trails.

I've not done much with oil fed turbos, just aerochagers. But I would want more oil (that will help take away heat) and water cooling line
 
i like what you are doing, i turbo'd my 94 vmax 600 4 years a go , 10psi was real fun . it would keep up with my buddys rev 800. good luck on your build
 
my airbox seems extremly restrictive my charge tube is about 1inch in diamater should i bump it up to a 2?
 
600srxman said:
what is the out let size of the turbo
the out let flange on the compressor housing is about 1inch ID the inlet on my air box is 1 1/4 ID i was thinking change my airbox to 2 ID and run a 2 1/4 charge tube.
 
also i believe the turbo cant supply the air it needs before it spools up because i am using a 1 inch charge tube when i open the carbs it just draws all the air and chokes the motor before the turbo gets up to speed.
 


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