m1000 turbo

[scaredycat]

wondering if anyone has tried a smaller 25 series turbo on a 1000 yet and
if so what were the issues....

i could see boost creep and overheating issues with the internal wastegate etc but looking for any other issues..

 

[WyoBoy1000]

It wont work, plane and simple

 

[scaredycat]

thanks wyo but i need more info as a reputable turbo shop didnt see a problem and another shop thought it might be hard to tune....has anyone in here tried

 

[RACINSTATION]

Itll "stack" heat. Not big enough to move the air that the 1000 motor needs to move efficiently. The 800 likes the 2860 and 2871 and the 1000 likes the 3071 or 3076. It is simple mathmatic efficiency.

 

[WyoBoy1000]

thanks wyo but i need more info as a reputable turbo shop didnt see a problem and another shop thought it might be hard to tune....has anyone in here tried

I don't want to speak to soon, but that turbo shop can't be reputable to tell you that, I asked twisted years back and it was explained and said no way.

 

[scaredycat]

racin and wyo

just a theory but if a 25 is externally wastegated and the rear flange is 2.5 inch diameter exhaust flow...wouldnt that end the heat stack issue...i talked to some big reputable turbo builders and nobody has said no way just it will take some proper planning.

i can see the heat stack issue if you stayed with the tiny internal wastegate but not if you added an external wg.

plan is for pg at low boost 6-7 lbs and watercooled not that it would help the heat stack

appreciate the input

 

[RACINSTATION]

Have you talked to Garr or Travis at OVS?

They probably have the most external wastegate turbos out there right now.

 

[WyoBoy1000]

Whats the point, the only reason I could see asking is if you have a 25 and trying to save money, but the R&D will cost way more. The ability to flow more air through the intake makes a big difference. I don't know enough to tell you one way or another, just passing on what I do know.

 

[scaredycat]

thanks racin, ill give those guys a call tomorrow. saving money is something i dont mind doing and i love the r&d...i dont see why i cant keep the internal wastegate and mount an external to keep the head temps down and a constant exhaust flow rate.

one negative is i might have boost at idle..lol

i finished welding up both the plenum and a lower profile oil tank with push to connect lines to ensure they dont leak.

also did a custom air intake fitting for my filter on the lathe and milling machine so the tools are getting a good workout..coolant lines are done and
it actually looks pretty clean.

i think the hardest part of this whole job has been the fittings required for the turbo and oil tank etc...banjo fittings etc.. worst case scenario is the turbo wont work and ill have to change it out... no big deal

 

[Boyko]

wondering if anyone has tried a smaller 25 series turbo on a 1000 yet and
if so what were the issues....

i could see boost creep and overheating issues with the internal wastegate etc but looking for any other issues..

Good to see you are into doing R&D but even the 2871 with a .86 a/r has been tried on the 1000 before, you can probably get that turbo to work but it will be low on power, top and bottom and a real b!tch to tune as well. The problem starts in the turbine housing, A external waste gate will not help, you need so much flow through the turbine housing to make x amount of cfm out of the compressor. The turbine is just to tight on the 28 series and with a 25 series .64 ar is way to tight I don't think you will get it to rev up much at all. Your pressure in the exhaust is going to be to high.

The most common choices for the 1000 is the 3071 or 3076 with a .86a/r turbine housing. I think it is to small for the 1000 cat but there are no other choices. On a 1000 I tossed together a few years ago with a external waste gate 3071 .86 I was seeing 15psi in the pipe @ 10 pounds of boost. Some will say that is optimum personally I would like to see around 13 to 14 in the pipe at that boost level.

 

[scaredycat]

thanks boyko

great info and super helpful

its suprising that an m24 ar .80 wont flow an m1,s exhaust but it will flow
double the cc.s in a 4 stroke as its pretty much the same size as the one on
my brother in laws rx-1....4 strokes being more efficient must have everything to do with it as its working good on his..

the wastegate thing has me a bit confused...i thought its job was to control the exhaust inut to the turbo or to monitor its flow rate and keep it constant.....thus making sure the turbo wasnt overloaded for it capacity..

 

[scaredycat]

boyko, racin,wyo

i think the start of my confusion was the fact that turbos are sized for 4 stroke applications and the amount of exhaust gas produced from a 2 stroke is double approx..

i did phone at Garr @ OVS and he was super helpful...sounds like the 30 series larger turbine side and smaller AR compressor side is working well on both the m8,s and 1000,s

down side is i now need to find a 3071 and sell my m24..

 

[Boyko]

2-smokers do put out a good volume of exhaust, another problem is the blow down time were the fresh charge pushes the exhaust out, you can not have a lot of pressure in the pipe.... no exast valves so it is a balancing act between the 2 sides of the turbo.

You shoud post some pics, cool project you got yourself spun into

good luck with it

 

[scaredycat]

lol, i could post a few pics but i spent all night tearing it all down and putting it back to semi stock.....on the bright side the coolant lines are ready, the oil lines , mounting bracket ,oil can,catch can,intake boost lines,air fuel,blah blah blah is all done...man...i think i stressed poor Garr abit when i told him a turbo place said it would work....lol i think he hears it more than once and i would bet that he wishes all turbo repair shops had a better understanding the mechanics of two stroke engines. i did get a better understanding and i think it leads me to believe that a 3071 has the best turbine size for a 2 stroke 1000 and a smaller AR opening for the compressor side is working and the tial v band is making it better yet....think this is right ....not sure but it seems this is still being perfected....glad i listened to you guys and thx snowest..