pulley combinations?

[cdooz]

can anyone tell me what pulley combinations make what boost on a nytro mpi stage 1 supercharger?

thanks in advance

 

[HYFLYR]

What altittude, it makes a difference?
22/26 at sea level is about 9-10psi.

 

[cdooz]

I AM AT ABOUT 650', SO SEA LEVEL NUMBERS WILL BE WHAT I NEED. THANKS

 

[Riceburner]

It is all here for RX 1 & Apex.

Noticed later you were looking for Nytro. Sorry I do not have that.

http://www.ty4stroke.com/viewtopic.php?t=84128

 

[darrin@mpi]

depending on elevation (10k) a 23 31 will make 10-11 lbs. 23 31 is how we ship our stg 1 unless customer is looking for something pump friendly. A 25 29 will get you 7-8 @ 10k and work with pump gas. The stage 1 will make 15-16 pounds at sea level with 23 31. all of these numbers are also based on a target rpm of 8800. Another way to adjust boost is tug the motor down in rpm with your clutching. You would be surprised at how well the nytro pulls at 8200.

 

[Phyxius74]

depending on elevation (10k) a 23 31 will make 10-11 lbs. 23 31 is how we ship our stg 1 unless customer is looking for something pump friendly. A 25 29 will get you 7-8 @ 10k and work with pump gas. The stage 1 will make 15-16 pounds at sea level with 23 31. all of these numbers are also based on a target rpm of 8800. Another way to adjust boost is tug the motor down in rpm with your clutching. You would be surprised at how well the nytro pulls at 8200.

What would be a suitable combinaition of pulleys for sea level and pump gas?

 

[rj998]

depending on elevation (10k) a 23 31 will make 10-11 lbs. 23 31 is how we ship our stg 1 unless customer is looking for something pump friendly. A 25 29 will get you 7-8 @ 10k and work with pump gas. The stage 1 will make 15-16 pounds at sea level with 23 31. all of these numbers are also based on a target rpm of 8800. Another way to adjust boost is tug the motor down in rpm with your clutching. You would be surprised at how well the nytro pulls at 8200.

What would be a suitable combinaition of pulleys for sea level and pump gas?

28/28

 

[SWENytro]

depending on elevation (10k) a 23 31 will make 10-11 lbs. 23 31 is how we ship our stg 1 unless customer is looking for something pump friendly. A 25 29 will get you 7-8 @ 10k and work with pump gas. The stage 1 will make 15-16 pounds at sea level with 23 31. all of these numbers are also based on a target rpm of 8800. Another way to adjust boost is tug the motor down in rpm with your clutching. You would be surprised at how well the nytro pulls at 8200.

What would be a suitable combinaition of pulleys for sea level and pump gas?

28/28

1) What is the ratio whith 23/31(10-11lbs)? and is 23=engine and 31=S/C?
2) I have 26T engine and 28T S/C what is my boost? ratio must be 0,92.? Or am I wrong?

 

[HYFLYR]

Regardless of what anyone tells you your boost is you should have a boost gauge on your sled, whether it be mechanical, liguid filled, or electronic, you need a boost gauge and hould have a a/f gauge as well. To go off what someone tells you is crazy. Each engine, clutch setup, gearing, track, rider weight, etc etc is a variable and needs to be tuned to each sled. IMO.

 

[sheetwright]

Also depends on engine mods and or the compression you ate running. Did you do any, and what elevation are you at?

 

[SWENytro]

I run at sea level, and I have a liguid filled boost gauge, but not a A/F gauge. And want to know how much S/C is capable of delivering 28T engine/28T top at 8000rpm and 8200rpm.
It's a Yamaha 180hk kit with other MPI gem. Do not know what separates the original MPI gem, but I think it was locked. I run with oginal compression. Now it's 26T engine and 28T top and the boost at 8200 is ~4.5-5psi.
But as you say "Each engine, clutch setup, gearing, track, rider weight" plays a role. But some bull...? if it was so important it would be impossible to run the powder one day and packed second. So sensitive it can´t be. I will not race just play. ;-)

The end of this winter, I want to boost up the engine! Thinking of 11.5 psi boost. What ratio should It be at sealevel?
I need to lower compression, new fuel pump and possibly new injectors. Cold air intake.
Thinking of switching away the MPI-GEM and install a Power Commander V and a Power Commander Auto Tune!?
Has anyone tested it on a MPI-S/C? Someone who drives with it?