Carbed 2 stroke turbo guy's !!!
- Thread starter gus bohne
- Start date
No one made a kit for them, but it would be a good candidate for a 2860 or a big 53 frame aero.
you could use the airbox from the aero mach z triple kits ,,, get one used.
Gus
you could use the airbox from the aero mach z triple kits ,,, get one used.
Gus
A little update on my project: The exhaust is done. I built the muffler so that I could repack it if necc. The oil tank is done. It has some baffles in it to keep the oil from sloshing out even if I tip it over. I also put a sight guage on it to keep track of the level. I've also got the pipe seams reinforced and found some 40# rated exhaust springs 240# of hold down with just six springs
I did some testing on the fuel pump at Gus's suggestion and found it to be lacking even with carbs at 10psi boost, so I've got a bigger one with still an acceptable current draw. The injection pump tested just fine and I'm going to keep the lower circuit in use for lubricating the pump shaft and gear.
I plan on taking the motor out of the chassis now and doing some work to it and the chassis and suspension. Better get busy the snow will be here next month.
I did some testing on the fuel pump at Gus's suggestion and found it to be lacking even with carbs at 10psi boost, so I've got a bigger one with still an acceptable current draw. The injection pump tested just fine and I'm going to keep the lower circuit in use for lubricating the pump shaft and gear.
I plan on taking the motor out of the chassis now and doing some work to it and the chassis and suspension. Better get busy the snow will be here next month.
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What are you guys doing to test your fuel pumps?
Guessing you are checking flow at pressure, but how much flow do I need?
I just happen to have a pump here that is rated real close to the MSD pump recommended but I would really like to test it before I use it. It is 90psi max and 49gph free flow.
Guessing you are checking flow at pressure, but how much flow do I need?
I just happen to have a pump here that is rated real close to the MSD pump recommended but I would really like to test it before I use it. It is 90psi max and 49gph free flow.
250 hp or there abouts.
thats very high pressure and low volume, must be small inlet outlet too.
I will go on record as stating that fuel demands in SNOW / altitude LOW LOAD conditions are much less than on the flats.
flats require 2-3 times the pump and line sizes. high load, high g's causes fuel to stall in the lines adding to the problem. 2.0's are the bare minimum, 12-18 over boost fuel pressure is just what you need to run with high load in sea level air.
If it can't fill a 1 litre bottle (through the bowl with drain plug removed ) in 12 seconds or less at 10 psi it won't work for me.
Gus
thats very high pressure and low volume, must be small inlet outlet too.
I will go on record as stating that fuel demands in SNOW / altitude LOW LOAD conditions are much less than on the flats.
flats require 2-3 times the pump and line sizes. high load, high g's causes fuel to stall in the lines adding to the problem. 2.0's are the bare minimum, 12-18 over boost fuel pressure is just what you need to run with high load in sea level air.
If it can't fill a 1 litre bottle (through the bowl with drain plug removed ) in 12 seconds or less at 10 psi it won't work for me.
Gus
WOW! that feeding some serious HP (500+??
). Now ya got me thinking Gus. edited: got me thinking even more that's 500hp per carb worth of fuel flow.......Yahooooooooooooooooooo!
I just put my regulator on the pump sitting on my bench with a small inlet hose and restrictions, and measured/timed flows at the various return pressure settings. My biggest concern was measuring voltage drop and current draw which was acceptable for my system. Now, I've got to go back and test through a carb to see what it really is through the needle and seat.
Of course my saving grace is that I am not worried about the kind of HP you are dealing with. I only need about 1/2 of that fuel.
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That's close to the specs on the pump I'm going to use. Here is a link to a spec page for it:
http://www.autoperformanceengineering.com/pics/gsl393.jpg
I'm pretty sure this pump was designed around a 43PSI @35GPM use. Since I should only use about 26gpm at 20psi I tested at 30psi to make sure I had plenty of reserve. I was really close to "just fine" with the stock EFI pump, but no reserve.
Good luck on your project.Tony, you can get big float valves for the cutlers from wahl bros.
Once you have your sled running, do another test for reference to fuel pressure and float response to load.
. with engine idleing, slowly increase fuel presssure tilll the idle changes. Now drop pressure back 2 - 3 psi. Make note of the pressure at which the idle dropped.
Now you know the point in bosst build where your pump pressure overcomes the float valve .
One other test to synch carbs to each other fuel response and volume wise is to run the pump with engine OFF, taking note of fuel level thru the powerjet line and vent lines.( best to do with airbox off and carbs in reed boots. ) slowly raise pressure till you see the fuel level move in th epower jet line and or vent lines. Make sure you check each carb closly as if one is ahead of the other you need to adress why.. A lagging float or one the doesn't sink within 1-2 psi of the other is gonna be a issue with unexpected leanouts.
Once you have your sled running, do another test for reference to fuel pressure and float response to load.
. with engine idleing, slowly increase fuel presssure tilll the idle changes. Now drop pressure back 2 - 3 psi. Make note of the pressure at which the idle dropped.
Now you know the point in bosst build where your pump pressure overcomes the float valve .
One other test to synch carbs to each other fuel response and volume wise is to run the pump with engine OFF, taking note of fuel level thru the powerjet line and vent lines.( best to do with airbox off and carbs in reed boots. ) slowly raise pressure till you see the fuel level move in th epower jet line and or vent lines. Make sure you check each carb closly as if one is ahead of the other you need to adress why.. A lagging float or one the doesn't sink within 1-2 psi of the other is gonna be a issue with unexpected leanouts.
Wow! Thanks for the info Gus, I was wondering if my 1.8s would work. I assume when you say big you mean 2.0s?.......just another reason we pay you the big bucks to keep monitoring this thread.
those might be tight but we don't knwo till you test. I think you'll be ok for altutude.
Gus
Gus
gus on 900 cat with CPI mitsu kit how many steps richer is a safe place to start on my jetting? Also where should i start my power jets at. thanks..
Sorry, I have no experience directly with the cats.
wish I could give you more.
Gus
wish I could give you more.
Gus
where can a oil pump for a non-bearing turbo be purchased, and how much?
CPI sells the greylor unit, there is another that I believe twister sells as well.
I have 2 greylor units from cpi that are 4 years old and still pumping.
Gus
I have 2 greylor units from cpi that are 4 years old and still pumping.
Gus
talk to mattymac, he just sold his kit, but I imagine could get you started, he ran a 900 cat with a cpi setup.
S
Spaarky
Well-known member
Twister is the man with the journal bearing pumps!!!! If you need some contact info PM me. CPI purchased a handful of pumps from him last year.. sounded like they want more too...
T
Team Voodoo
Active member
fuel system
Can you tell me if I have the right fuel system for my 440 rotary valve turbo project. I'm using 38 mill carbs, power jets, msd 2225 fuel pump, 4309 fuel regulator, My biggest concern is the carbs, should I change out the float needle valve to something bigger or leave it stock?
This is for radar running.
I'm about 750 feet above sea level.
Mike.
Can you tell me if I have the right fuel system for my 440 rotary valve turbo project. I'm using 38 mill carbs, power jets, msd 2225 fuel pump, 4309 fuel regulator, My biggest concern is the carbs, should I change out the float needle valve to something bigger or leave it stock?
This is for radar running.
I'm about 750 feet above sea level.
Mike.
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your fine.
Hey Gus this is a GREAT thread! I have a blow through turbo 500cc turbo drag banshee with 32mm mikuni's and it makes 25lbs of boost on a 300ft race.Will I see any performance gain with bigger carb's?
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