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Carbed 2 stroke turbo guy's !!!

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Ok, read trough the post again.
I am trying to figure out what stuff i need to buy/fabricate.
-Turbo, probably a garret gt28 series, got som friends that are tuning their nissan s-13/14. They got a lot of diffrent turbos laying around.
-Fuel pump. Might be able to use a walbro pump i have.
-Bypass fuel regulator.
-Power jets. One on each carb should be enough i guess. I see that some people are running one on their charge tube.
-Oil pump for the turbo. I would really like to still be able to use the stock oil injection. So i guess a electric oil pump is the way to go for me. Found a pump that should do the job. A bit expensive, but this is a pump that is made to pump hot oil. http://www.rbracing-rsr.com/oilsystems.htm
-Converting my electrical system from ac to dc and add a small battery.
-Fabricating a intake plenum.
-Refabricating the stock singel pipe, add a muffler or maybe rerouting the exhaust to the tunnel.
-Maybe lower the the compression. I can think of two ways of doing this. Machine the head or adding cylinder base gaskets. The last one will sqrew with the port timing.
-A lot of fittings, hoses, oil tank and stuff...

I have tried to make a list of some details around the build it self.
-The intake plenum box should be 2X deeper then the diameter of carb throat diameter.
-Regulator set at 3-5psi at idle. Getting the referance from the thick part of the singel pipe
-Powerjets as close as possible to the slides.
 
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for an 800 sized motor, the 2871 with the .86 housing is AWSOME. they come out of the hole hard and make great top end. thats the exact turbo you want for this app IMO>

and for the oiling for the turbo, I have seen lots of people run tiny little pumps as the garrett ball bearing turbos need VERY little oil pressure to stay alive. also, you can just run your injection pump to drive turbo oil and premix your gas, works good, is simple, and the pump is mechanical and you know its working if your motor is spinning.. and I just dont trust little electric pumps much, but thats me.. simple, cheap, clean.
 
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What about power jets? Are the thunder powerjets any good?
I am a bit worried about running a electric pump. A low pressure warning light will be installed. I might ask the machine guys at work to fab me a mechanical pump to replace the stock injection pump. But they have a lot of work at the moment. But then I have to drill the upper part of my case for lubing the PTO bearing. Any good links on how to drill the holes?
 
This summer i am thinking of getting a small carbed motor(500-700cc) and doing another turbo tube sled. If your wondering what im talking about, Check out my sled build in the members sled builds under project skidoo X

The sled is flat out awsome and all i could ever want. Just looking to do one for a buddy but with a lighter motor with a motor that can handle boost well.

My question for you guys is what would be the best small sled engine to put in this project? Light, simple and great under pressure. Dosent have to make crazy power but need some. Im thinking a little over 200 horse at 10k. Im also wondering about Building the motor up for the boost. Porting, bore, stroke, pipe, and anything else that might make the motor work better under pressure.
THANKS for any help
 
I wish I would have read all about turbo charging a sled in this forum before is did mine. Going to do some changing of some things to make it work better, but i am still in the early testing stages. The question is what are power jets and how do they work with current jetting and turbo's

thanks
Doug
 
My question for you guys is what would be the best small sled engine to put in this project?

The Poloris 600 motor is excellent and is light. The old Polaris 700 big block motor and the old Rotax???(dont remember size) are some of the best two motors. Not the lightest motors though. They are tough as nails, and cheap to fix if you screw something up. I like the old Polaris 700 big block myself, but am a little bias. You can beat the crap out of that motor and it will never die.
 
hey guys

i have a turbo 670 that i am building in a racer x custom chassie. the 670 had hobb switch with the stock fuel pump and when the hobb switch sensed boost it would turn on the electonic fuel pump. i have ditched the hobb switch and stock fuel pump for just the eletronic fuel pump, but when i run the eletronic fuel pump at an idle it seems to just pump fuel straight into the motor and i have my fuel pressure regulator set at 5 psi and then it will go to 14 under boost. question is do i have to change anything on the carbs to run just the electronic fuel pump or do i have to run the hobb switch with this system?

thanks Rob
 
Couple questions?

I picked up a used .53 aerocharger turbo kit for my 02 rmk 700. I have a question about intercoolers, I was told that you cant use an intercooler on a carbed engine? Is this true? If so why?

Also my engine is pretty stock, is there anything that should be done? I know the exhaust valves should be pinned open. What about the bottom end? Thanks guys!
 
Who told you, that you couldnt use a intercooler? IMO that is false. Plus, look at all the two strokes kits that have variations of an intercooler. Whether it will actually help you or not, again IMO that is questionable. If you are going to use one, I like the one that Curt @ Fastrax is using. I dont know if this is one that Curt came up with or your kit builder.

Bottom end, get your primary balanced. As a precautionary, you could have IndyDan go through your crank and cases. Other than that maybe a little work on your head, depending on the fuel you are planning on running. Some guys have gone to some turbo specific porting.

Patience is a vertue, the other guys will speak up.
 
Thanks Outlaw, I believe what the person who told me that was referring to my application specifically. Being that im only running 10lbs of boost, so I wouldnt need an intercooler. It did not make sense to me thats why I asked.

Planning on having my primary balanced at fastrax along with picking up one of there engine plates. As far as clean up, im not sure what you mean by that? What about the over sized PTO bearing, good idea?

Thanks again!
 
hey guys

i have a turbo 670 that i am building in a racer x custom chassie. the 670 had hobb switch with the stock fuel pump and when the hobb switch sensed boost it would turn on the electonic fuel pump. i have ditched the hobb switch and stock fuel pump for just the eletronic fuel pump, but when i run the eletronic fuel pump at an idle it seems to just pump fuel straight into the motor and i have my fuel pressure regulator set at 5 psi and then it will go to 14 under boost. question is do i have to change anything on the carbs to run just the electronic fuel pump or do i have to run the hobb switch with this system?

thanks Rob


So what you are saying is the motor is flodding at idle? you should be fine the way you are set up. you can turn down your fuel pressure a couple psi if you want but you are in the ball park of where you should be.

then if you see 14 psi on booost that is telling you your reference to the regulator is seeing 9 psi of boost. if that is what boost level you are at then you are good. :face-icon-small-hap
 
I picked up a used .53 aerocharger turbo kit for my 02 rmk 700. I have a question about intercoolers, I was told that you cant use an intercooler on a carbed engine? Is this true? If so why?

Also my engine is pretty stock, is there anything that should be done? I know the exhaust valves should be pinned open. What about the bottom end? Thanks guys!

i never pin open my exhaust valves. just leave them the way they are stock. this will keep your crisp bottom end.

yes you can install an intercooler. the biggest thing that i find with inter coolers is mounting location you need to install them so that air can get to them. if not the intercooler begins to hurt performance after it is heat soaked. so look at design and weigh out goods and bads.

the lower the inake temp the better the sled will run and act. plus build more power!!!:D
 
-Converting my electrical system from ac to dc and add a small battery.
-QUOTE]



another way to convert you ac to dc is through a rectifier. you can buy them at radio shack. when you hook them up take the pos and neg from the startor and run them to the outer sides then hook your fuel pump to the other and ground the rectifier.

make sure that you get both pos and neg from your stator or you will only get 6V to your pump or pumps.

or anotther way is to install a relay and capasitor to take off the bottom ac wave.
 
Mach Z 780

Paid for a membership just for this thread! I have an old Mach Z that used to be a nitrous lake racer sled. Want to put it on asphalt this summer! Would a T3/T4 be suitable for this application? If not, have any good ideas? Cost effective is the name of the game, I don't want to go pro or anything, just have a little fun bracket racing. Stock pipes? I have a set of CS 1025 trail pipes also. Best thread I've ever read, PERIOD! Thanks Guys!!!
 
They go by the total hp. If the motor makes 150 and you want another 150 out of the turbo, you will need a turbo that is good for 300+. Turbobygarrett.com has a comparision chart for all their models.
 
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