How does a guy test to see if his power jets are in the right location? and how do you know how long to cut the pito tube? at what throlle position should the needle stop and powerjet take over? Should a guy put leaner needles in and use more powerjet or am i backwards?
Carbed 2 stroke turbo guy's !!!
- Thread starter gus bohne
- Start date
T
Team Voodoo
Active member
Cool thanks.
Where is the best location to put the rising rate boost line to prevent burn down. I noticed in a past post of yours you mention the middle of the pipe but which pipe? The one going to the intake boost box coming off the intercooler or from the turbo to the intercooler or the exhaust pipe.
In the exhaust gives you a better rise vs demand. center of the fat part of the pipe, #4 line .
Gus
Gus
I got a couple questions that might also answer this one too.
The powerjet that goes in the charge tube. I assume you want it close to the turbo, farthest from the carb as possible? Also the length of tube on that one probably doesn't matter a lot because if the turbo is blowing its going to fuel.
Now on to tuning the powerjets. When you need to adjust them do you adjust all 3, or just the carbs?
Gus
I assume your last post you mean 4mm line.
Your Greylor pumps, are they pumping to journal bearings and are they 12v or 24v.
Twister doesn't have any pumps and isn't sure if or when he will get more. I got to get this thing together so I am looking for alternative pumps at least until I can get one of his pumps. Only got a few more weeks before I need the sled done.
#4 line size,
i have a power jet in each carb and one in the charge tube tha[ is running through a hobbs swich and solinoid to turn on at 3 psi. ny question is how do you know that the main jet isnt to lean or rich? if its on the powerjets mostly.
Main jet probably isn't a big concern because you are supplementing with the powerjets. If your main is a little small or big you just add a little more or less through the powerjets.
so is there any rull of thumb how many steps richer to start?
You dont necessarily richen the base carb setup at all. In fact, you will likely lean it down.
As air speed through the carb is raised, it siphons fuel way way better. So, you dont need as much jet size as you think.
Jake
As air speed through the carb is raised, it siphons fuel way way better. So, you dont need as much jet size as you think.
Jake
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BINGO !!!
good response,,Jake.
the overlap of circuits can vary widely. some run 3 turns out ofn powerjets, and small mains, others 1 turn out and larger mains. There is NO blanket answer to this, its more effected by clutching and on aeros vain orientation.
Using the vacum side of the aero controller will cause a completetly diferent curve than NOT using it.
fixed schroll housings with wrong ar's can go to one side or the other also.
evaluate the rich or lean spot as far as rpm, load and throttle psoition, then you can make a decision as to what ciruct or circuits need adressing. many time we lean one only to enrichen another so as to not create another bad spot.
Gus
back in the early 80's we ran the third powerjet in the charger or tube, havent used that set up since then . no gains only harder overall tunign and consistency,, but ,,,,,, to each his own.!
no ONE set up is best for everyone.
good response,,Jake.
the overlap of circuits can vary widely. some run 3 turns out ofn powerjets, and small mains, others 1 turn out and larger mains. There is NO blanket answer to this, its more effected by clutching and on aeros vain orientation.
Using the vacum side of the aero controller will cause a completetly diferent curve than NOT using it.
fixed schroll housings with wrong ar's can go to one side or the other also.
evaluate the rich or lean spot as far as rpm, load and throttle psoition, then you can make a decision as to what ciruct or circuits need adressing. many time we lean one only to enrichen another so as to not create another bad spot.
Gus
back in the early 80's we ran the third powerjet in the charger or tube, havent used that set up since then . no gains only harder overall tunign and consistency,, but ,,,,,, to each his own.!
no ONE set up is best for everyone.I was told the powerjet in the charge tube because the fuel in the airstream helps cool the intake charge.
Myth?
Its tough sometimes trying to decide what to beleive. Sometimes people think they know what they are talking about but really don't.
Myth?
Its tough sometimes trying to decide what to beleive. Sometimes people think they know what they are talking about but really don't.
T
Team Voodoo
Active member
turbo
I have this turbo new in the box and I'm not sure if it will meet my needs or not. I going to use a automotive turbo because it's not in the budget for a aerocharger at this time. So my question is will it work on my project.
1998 440 rotary valve engine
38 mukuni carbs
single stock pipe
race porting
Air Inlet 1.75"
Compressed Air Outlet 2"
Turbine Housing Flange Standard K03
Exhaust Outlet 3-bolt
Cooling Oil and Water Cooled
Working Pressure 6-25 PSI
Compressor Wheel 36 /50mm
Turbine Wheel 40.50 /45 mm
I have this turbo new in the box and I'm not sure if it will meet my needs or not. I going to use a automotive turbo because it's not in the budget for a aerocharger at this time. So my question is will it work on my project.
1998 440 rotary valve engine
38 mukuni carbs
single stock pipe
race porting
Air Inlet 1.75"
Compressed Air Outlet 2"
Turbine Housing Flange Standard K03
Exhaust Outlet 3-bolt
Cooling Oil and Water Cooled
Working Pressure 6-25 PSI
Compressor Wheel 36 /50mm
Turbine Wheel 40.50 /45 mm
what is the turbo and what is the a.r #
the best 440 cylinders were from the 9500 family 1982 for turboing.
Gus
the best 440 cylinders were from the 9500 family 1982 for turboing.
Gus
T
Team Voodoo
Active member
The 98 440-454 cylinders are pretty much the same as the early 454-440 cylinder exept the 98 are nikasil for better cooling........
The turbo is a knock off kkk k03 borg warner.
compressor 36 a/r
turbine 87 a/r
S
Spaarky
Well-known member
Twister built my turbo set up last summer/fall/winter... hahahahaha I had it out on two different trips. The second trip was just him and I, a tuning trip so to speak. The first day we spent on his sled until we ran out of belts for it, and the second day on mine.
I was getting frustrated on the first trip out, he could tune my sled in a matter of minutes. I would be all over board with it. Its just getting used to the sound and feel of the sled. This is how he taught me:
First he came over and opened all the power jets wide open. Then he had me turn down the charge tube power jet(1/4 turn at a time) until the bottom was clean. I would make a couple runs and then adjust the fuel. Then after that was clean we went after the carb power jets(1/4 turn at a time). After about a half day, we would take turns jumping on my sled, and I could almost predict how far it needed to be turned down.
One of Twisters tuning aids is his remote adjusters for the power jets. Its awesome you never have to open the hood. Make a couple runs, reach down on the dash and adjust your fuel.
Another thing is run really good fuel. It saved my butt in the learning process a few times.
I want some of those remote adjusters !!
get me his contact info.
I think that will work for the 440, Mike mazur in rockland maine has older aero 99's NEW for 500$ old style but they work and are cheap.
Otlaw addict, send your info to my e mail
gus.bohne@comcast.net.. I have something for you ....!!!!
get me his contact info.
I think that will work for the 440, Mike mazur in rockland maine has older aero 99's NEW for 500$ old style but they work and are cheap.
Otlaw addict, send your info to my e mail
gus.bohne@comcast.net.. I have something for you ....!!!!
id really be interested in the remote adjusters as well. russell3571@aol.com thanks...
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