Think I blew the motor today !

[full tilt viper]

Running stage 1 nitro with extra fuel pump and cold air kit 25x29 pulleys @8 lbs .91 octane ethanol free. Had MPI do the timing and temp ECU reflash this season to help pull out some timing etc. Sled has been running really well. Good cold running conditions today with 3 inches of fresh snow.Water temps 169-174 , afrs mid cruise 12's low 13's. WOT 11.6-11.9. Did a few 1000' lake and field pulls nothing to long. Without warning just doing a slow turn around after a good blast I lost one cylinder and it spittered and spattered running on 2, Shut it off and saw oil not alot at the base around the bottom pulley. I had no check eng lights or warnings . When I restarted it sounded bad still on two cylinders, blowing alot of smoke and some oil I didnt thow a rod the case is good and intact. Oil pan and oil filter look normal The motor is dry from the top of the oil pan up .The oil and blowing smoke seems to be blowing out the base pulley side near the botton . I checked the plugs 1 is good middle is soaked in oil, 3 is good. I seem to be pushing oil out the exhaust also. Any ideas on what you think is going on ? I thought I had dome all I could have to help prevent this, pissed !

 

[ghost rider]

I'm not familiar with your engine but your set up and AFR numbers are spot on.
91octane is cutting it close IMO. Is there any water in your oil?

Barry

 

[Srxspec]

If your 1000' lake and field runs were back to back, it likely scored the middle cylinder. If you're lucky you can get away with a new piston & rings (check the wrist pin area of the other two pistons as they can/will show scoring if they got hot as well), if unlucky it has damaged the cylinder wall as well. I have rebuilt many of these and can help you out if you have any questions.

 

[ghost rider]

If your 1000' lake and field runs were back to back, it likely scored the middle cylinder. If you're lucky you can get away with a new piston & rings (check the wrist pin area of the other two pistons as they can/will show scoring if they got hot as well), if unlucky it has damaged the cylinder wall as well. I have rebuilt many of these and can help you out if you have any questions.

Is this common ?

 

[full tilt viper]

Oil level is up and clear . My biggest worry is how can I stop it from happening again . And what caused it in the first place ? At this point I don't know if I should I put in a used motor or rebuild this one and build it up to make even more power ( am I nuts ) .

 

[suburban]

Sounds like you found the limit of 91 oct at your boost level. Gonna need to lower the boost, or up the octane. Even with your reduced timing.
if its been running at this level, maybe you got a tank of fuel that was less than 91 oct

 

[ghost rider]

Above X2
I keep my octane 4-6 points higher than my minimum octane requirement, just in case there is a variance at the pump.

 

[sheetwright]

Sent you a pm. We are a bit apart, but my motor, fuel system etc might be able to help you over a rebuild if interested? I was running 13lbs with 91 octane and torco. My 08 did what yours did a couple times when Hauck built it. This time I went to ulmer on my 20110 and no issues here

 

[Vmax4]

What elevation are you" field and lake runs" happening it.......

 

[full tilt viper]

Ya could have been a fuel issue. Was hoping the reflash might have helped with that. I'm running 300-400' elevation. Wasn't even running it that hard . Ran perfect all day with no sign of a problem at all. Seems like that's when they tend to let go. So many good parts on this sled I might just part it out . How much should I expect pay for a motor job ? Allen said might just be piston and rings ? But if I'm gonna pull the motor any thoughts on how I should build it up and what parts should I consider putting into it. Havn't got your PM yet about your motor.

 

[sheetwright]

I'm such a dumb a$$ lol. I pmd ghost rider by accident. I will send over soon. My setup is for up to 13lbs fyi.
And Allen built it

 

[ghost rider]

I'm such a dumb a$$ lol. I pmd ghost rider by accident. I will send over soon. My setup is for up to 13lbs fyi.
And Allen built it

No problem.... I was wondering why you thought I may need a nitro engine.
If I did yours would be king.... Very nice set up!

 

[sheetwright]

Thanks lol. That what I get for trying to pm off of a little phone screen.

 

[rxrider]

Please run the best pump fuel you can get.
I would never run 91 octane no matter what as long as boosted, not even at low boost levels.

 

[Yamadog]

What did you do to the motor to run that 8#'s of boost? head gasket or low compression pistons? I blew up my brand new viper with 867 miles on it a 6#'s of boost at about 1000 ft of elev..

I rebuilt with carillo rods, wiseco low compression pistons and quick spool waste gate & upgraded fuel pump. Even with the low comp psitons it has more power at 6#'s and can run it up to 12#'s. I put a switch in set for 6 and 9 for now. These motors are more particular than the 4 holer and 10.9 to 11.4 is the tartget on the AFR I am running. I am riding with 2 gallons of 110 race gas and always blend with 91 pump gas but they told me that I don't have too, I don't believe them anymore. The worse thing I will do is lose the censor.

Hopefully you did not hurt the block at $2200 they are a bit pricey.

Good Luck and get her back out there