• We are no longer supporting TapaTalk as a mobile app for our sites. The TapaTalk App has many issues with speed on our server as well as security holes that leave us vulnerable to attacks and spammers.

any high milaege turbo owners?

vcrash

Pro
Joined
Apr 14, 2003
Messages
170
Location
muskoka
I now have three thousand miles on the cpr turbo running many differant boost levels and would like to talk to any guys that have put comparible miles on there sleds regardless of what systems you may have, Thanks
vcrash
 

I have 1750 and hope to get over 2000 before the season ends. I would like to discuss crankcase ventilation, clutching thoughts and boost levels as they effect clutching. The one problem I am having is at sustained high speed runing, 120+ on speedo, I am blowing oil out the crankcase vent.
 
Yep, those are good topics. I would add:

- Jetting considerations WRT fuel pressure, starting hot engine, WOT.
- Adjusting boost threshhold to help hook-up.
- Lessons learned, things to watch for...
 
I added a coolant shutoff on the carbs and it has made a ddifference on the hard starting.
 
Buck, on 2 occasions that i know of i have also blown a substantial amount of oil out the vent, unfortanatly it was days of long rides so im not sure what condition caused it, it was enough oil that it covered the inside of the primary sheave but didnt get on the belt, on the clutching issues theres one thing i cant figure out, whether im at 7.5, 9.0 or 12 pounds boost the sled always revs the same which is around 10400, i would think that i would have to reclutch for the differant boost levels but i dont which is fine for me,the opening of the throttle to start is no differant on mine then it was before i installed the turbo, sometimes i have to and sometimes i dont,Buck, does your mc unit bolt directly onto the header with the header supporting the wieght of the turbo?
 
Yes the turbo does mount on top of the header pipe collector. The exhaust is mounted to the back of the turbo and curves down, so I suppose that also helps to support the turbo.
As far as clutching, my will pull 400 less at 8# then it does at 12#'s. I have a 2 stage electric boost controller. When I push the button it jumps instantly 400 rpms.
 
2600+mi. so far. Installed from new. Also installed a shutoff switch to stop coolent supply to carbs. I was having the same hard starting issues on warmer days, and that stopped the problem. Boiling fuel is not very forgiving in this motor.
 
vcrash if you are changing boost levels and not seeing any change in RPM there is something wrong and your not making any more power.
 
vcrash if you are changing boost levels and not seeing any change in RPM there is something wrong and your not making any more power.
 
vcrash: It sounds to me like you have a blow by issue. It also sounds like you are having the same issue's I had. As you increase boost it spits more oil. When you turbo charge any motor blow by will be amplified. especially with the ammount of RPM's the RX-1 spins. My sled has a blow by issue. From 6 to 10 pounds my sled spits very little oil. From 10 to 15 it's spits more oil then I care to talk about. IF my motor was solid it wouldn't spit any oil. We've had 4 units run our kit. Two were used, and 2 were brand new. The units that were used both spit oil. The two that were new spit zero oil at any boost level.

The one thing I think the RX-1 needs is more crank case venting. I'm not sure under turbo charge conditions a new motor will be able to keep a perfect seal forever. It might not be able to keep a good seal when you turbo charge it. If you add crank case vents this will also help stop oil from being forced out of the motor. By opening the crank case you give the air a place to vent thereby eliminating crank case pressure. Therefore the hot heavy oil can't be forced out of the motor.

as I increased and decreased boost levels my RPMs rose and dropped as well.
 


Back
Top