stage 2 boost numbers

[sheetwright]

What are the highest boost numbers/pounds you have seen on a sled using a stage two MPI kit on flatland? Their site says you could get over 18lbs out of this kit. What engine work did you do to get you there. I have the pistons work done now. Did you have the fresh air intake. Obviosly you could get more out of a stage three or a turbo. Just looking to see how far I could take this kit with the right setup in the future. Maybe Heath can chime in on this one.

 

[MattZx6]

I'm running @ sea level, stage II, stock motor, ARP head studs, water meth, 23/33 Pulley, regular intake (I have the new cold air intake waiting to go on), I was showing boost levels of 17.2psi at WOT(not spikes) last year.

Think I'll likely dial it back to 15psi and leave the motor alone. Anything I've heard is the rods are the weak point in this motor.

 

[sheetwright]

I'm running @ sea level, stage II, stock motor, ARP head studs, water meth, 23/33 Pulley, regular intake (I have the new cold air intake waiting to go on), I was showing boost levels of 17.2psi at WOT(not spikes) last year.

Think I'll likely dial it back to 15psi and leave the motor alone. Anything I've heard is the rods are the weak point in this motor.

I am also running meth injection, I am at sea level, have the fresh air intake on now, No new head studs, did have low compression pistons put in when the engine was stroked, but have a 16lb pulley from what the old owner says. They are dialing in the clutch close on the dirt track, and have hit 14lbs so far. The cold air claims are more fresh air , and 1-2 lb's of additional boost. So should I assume that I could actually get to 16-17lbs when riding hard? Say dragging on the lake? Also what is the largest size pulley one can run on the stage 2 safely on the Nytro engine? Also at what boost level do you need to go to new head studs, and/or possible shims on the Nytro? Thinking of the potential makes me and we don't even have snow yet

 

[heath@mpi]

std boost for a sea level stage 2 nytro will be around 16-17 but twith cold air intake and iac mod it will se about 1-2 more. and it can be pullied higher if you want more.

Hope this answers the questions

This is all assuming stock compression ratio

 

[sheetwright]

std boost for a sea level stage 2 nytro will be around 16-17 but twith cold air intake and iac mod it will se about 1-2 more. and it can be pullied higher if you want more.

Hope this answers the questions

This is all assuming stock compression ratio

Heath, what is the highest/safest pulley recommended for this kit, and sled. Also if I went higher, what other mod's would have to be done for the engine to handle this? Thanks for the help as usual

 

[heath@mpi]

Thats a silly questions to ask me haha.

What kind of rods and pistons are in your motor?

Head studs?

what kind of fuel do u run?

 

[kinger]

Sheetwright - have you driven a boosted sled yet?

Only reason I ask is I get caught up in the numbers game myself and what your building is going to be a friggen monster, seeing that your in IL and probably ride there or travel north I assume you like to trail ride, what you got is way too much for the trail, I am pushing the limits on my 10 psi apex I shimmed the head and run on 91 but I have jump and landed wrong, hit something, etc where I blipped the throttle on landing and was able to get back off of it before I got in serious wreck but I am confident if I do it again with the boosted beast I'm in trouble.

The mountain guys are building big boost because they are some serious snow, serisouly huge tracks, altitude, etc and have more leaway, 17+ psi at sea level on a groomed trail is NUTS, picture your sled at 150mph it will do it (track wont), picture a ice heave where you would normally hit at 80-mph now at 120mph because you just started accelerating, and I'm nuts and even I think that is NUTS. LOL

I would pulley it for 15psi and hold the F on, its going to give you some serious shoulder pains. ride it for a year then decide if you want 20+

I know its unsolicited advice which we all hate but something to consider. If your used to boost and it works great for how you ride then forget everything I said

 

[mulot30th]

I rode my rotrex c94 (similar to stg 3 from mpi) rx1 last winter... 16 psi (low boost and dump valve opened) and man this thing was nuts on the trail... no reason to need more than that.


BTW That was good for 280hp on the dyno.

 

[mbarryracing]

Kinger, right on!

 

[sheetwright]

Sheetwright - have you driven a boosted sled yet?

Only reason I ask is I get caught up in the numbers game myself and what your building is going to be a friggen monster, seeing that your in IL and probably ride there or travel north I assume you like to trail ride, what you got is way too much for the trail, I am pushing the limits on my 10 psi apex I shimmed the head and run on 91 but I have jump and landed wrong, hit something, etc where I blipped the throttle on landing and was able to get back off of it before I got in serious wreck but I am confident if I do it again with the boosted beast I'm in trouble.

The mountain guys are building big boost because they are some serious snow, serisouly huge tracks, altitude, etc and have more leaway, 17+ psi at sea level on a groomed trail is NUTS, picture your sled at 150mph it will do it (track wont), picture a ice heave where you would normally hit at 80-mph now at 120mph because you just started accelerating, and I'm nuts and even I think that is NUTS. LOL

I would pulley it for 15psi and hold the F on, its going to give you some serious shoulder pains. ride it for a year then decide if you want 20+

I know its unsolicited advice which we all hate but something to consider. If your used to boost and it works great for how you ride then forget everything I said

I agree with you guys. I am just thinking out loud for future stupid pipe dreams. What I have right now is probably be WAY to much for the trail, and will have to dial it down a hair. Like Hauck told me a lot of guys think they can handle power, but can you handle braking, or sudden changes? Which sounds more like it. The stories you here of racing up to a corner, or T section, and not being able to stop in time is a very scary thought. My thoughts are more for the future. If I decide to get another trail sled, or keep my Apex for the daily driver should I make this thing a fun drag sled with a wider front end? There are a ton of Apex, and RX-1 models out there that make a ton of power, but you don't see a lot of flatlanders with nytro's over 10-12 from what I see (probably because of the stance). The other thing that kind of peaked my interest is when another member said these have their walls (which all sleds do). What is ths wall on the Nytro if you went with studs, and pistons. So much talk about the 1200 thought I might ask. Since in my opinion they are in a closer class then the Vector. Which is totally different debate. There is always a sled with more potential then another, and the 1200 may have more potential. Just wonder sometimes, what mine can personally be? Even if I don't do it. Thats why I call it a pipe dream

Thank you for the concern, needed solicitation guys, and help. Nothing worse then a bad accident. Caused by one who doesn't have enough knowledge, or practice with unexpected power

 

[sheetwright]

Kinger, and guys thank you fro all of your help it is very helpful. Heath read your PM. Thank you for getting back to me so quick. That is the information I was looking for.

 

[crippledncrazy]

After reading what every one has wrote I have a couple questions? I am getting the stage two ulmer kit and meth injection from hurricane. Usually the kit is set at 8.5,with the meth I was told 10 lbs would be fine. I think this is well with in the realm of a trail sled? Does any one think I could actually go higher? Maybe like 10.5 or maybe 11 on the stock motor and be safe? I feel that these number will produce great power and can be managed on the trail? Just wondering what all of you had to say? I have never rode a boosted sled, I have rode my mach z 1000 with mods, heavily modded triple machs, and some srxs well ove 200 hp and that was a crappy handling chassis compared to the nytro. I also have never rode my xtx or any other nytro, some may think its not smart to get my sled boosted before ever even riding it but I think I will be fine. I have only done a couple rips in my back lawn and thats my extent of seat time on the nytro

 

[herby]

so after reading these posts i'm still wondering which pulleys are needed for max boost on stage 2. im putting the pro logger on this fall, so i would like to put on the max pulleys and go down from there depending on my situation (mountains or flatland).

 

[sheetwright]

Heath from MPI said with mine since I am running 100% meth with 91octane, and Carillo rods I should only go up to 18lbs to be on the safe side.He said the rods are the week point on these sleds, and the pistons are pretty strong. How High one can go with new pistons, and studs, I am not sure? I also have the prologger, and am thinking of doing it the same way. Just not sure when I could dial it down, and use and adjustable secondary like the Shockwave. FYI

 

[sheetwright]

After reading what every one has wrote I have a couple questions? I am getting the stage two ulmer kit and meth injection from hurricane. Usually the kit is set at 8.5,with the meth I was told 10 lbs would be fine. I think this is well with in the realm of a trail sled? Does any one think I could actually go higher? Maybe like 10.5 or maybe 11 on the stock motor and be safe? I feel that these number will produce great power and can be managed on the trail? Just wondering what all of you had to say? I have never rode a boosted sled, I have rode my mach z 1000 with mods, heavily modded triple machs, and some srxs well ove 200 hp and that was a crappy handling chassis compared to the nytro. I also have never rode my xtx or any other nytro, some may think its not smart to get my sled boosted before ever even riding it but I think I will be fine. I have only done a couple rips in my back lawn and thats my extent of seat time on the nytro

Here is the info the guys on here gave me on trail power From what they say you will be 10-1 with turbo as you will see in this thread

http://www.ty4stroke.com/viewtopic.php? ... ight=boost