boosted phazer rev limiter????

[Mini4]

Hey guys new to the site but not new to snowmobiling. I have a real weird problem with my phazer. It has a mcx turbo kit on it and since I have owned it it acts like it hits the Rev limiter around 10,500 and I understand that it should be more like 12,500 ish??? Never owned a phazer before only apexs so really new to this thing. It pulls like crazy and has tons of power. Clutching seems spot on. Not to sure what to think????? Appreciate any help.

 

[stingray719]

MCX press turbo kit some versions are lean on top end. I put an automotive boost enabled fuel pressure regulator on mine to even it up. Does your AFR say it is lean when this happens?

 

[Lashcat]

Add weight to the clutch. When I installed the SC I had to weight it up to keep it off the rev limiter.

 

[Mini4]

It's a little leaner than I would like. Usually runs around low 13 to high 12 on a wot pull. Took it out today but the snow here is crap now and it's really hard to drive and look down. It really is weird how it is acting when you wick the throttle. It will hit 10500 and act just like it's hitting the limiter. Then I will shut it off and ride some more and it will pull 10800 to 11300 or so with no rev limiter characteristics at all? Afr stays the same. It's all just really weird to me. Is there a sensor or something with the mcx that could be causing it?

 

[Mini4]

Ok I have spent a little more time on this thing and rode it a bit more and I think I have it narrowed down to mcx box being bad or an mcx injector. I changed and regapped plugs and installed fuel pressure Gauge. It shows good pressure all through like 42 lbs at idle and all the way up to 58-60 ish when boost comes on. I understand that that should be good. It still is popping around 10500 and the afr shows a lean condition starting at 15 and coming down to that 13.2 to 12.8 range. Has anyone had a mcx box go bad or an injector?
Thanks

 

[BurrFabrication]

What fuel are you running? Head shim? What didnyour old plugs looks like?

 

[stingray719]

Ok I have spent a little more time on this thing and rode it a bit more and I think I have it narrowed down to mcx box being bad or an mcx injector. I changed and regapped plugs and installed fuel pressure Gauge. It shows good pressure all through like 42 lbs at idle and all the way up to 58-60 ish when boost comes on. I understand that that should be good. It still is popping around 10500 and the afr shows a lean condition starting at 15 and coming down to that 13.2 to 12.8 range. Has anyone had a mcx box go bad or an injector?
Thanks

I had to buy a new MCX box. Odd thing though, if I started and immediatly took off the turbo wouldn't spool up right. If I started the sled and let it idle for about 15 to 20 seconds all would work well. Might try that.

OH, I ended up putting Nytro primary weights and a Mountain Max secondary on it and almost no lag and would lift the skis on takeoff.

 

[Mini4]

running 91 octane with head shim and the old plugs didn't look to terrible. a little on the lean side but not terrible