a big hp# like 180 out of a single may be possible with nitro.i am currious what kind of numbers a big bore nitro motor running on say 80%-90% would make,i wouldnt think it would last more than a few passes though.

 

180 HP? better put a scatter shield around that motor caus it's coming apart and no tools will be required [img]i/expressions/face-icon-small-happy.gif[/img]

 

I respect the new guy in town trying to make a name for himself but 180HP with stock cases????
look for his adds in the comics section.

 

Majorecho, Why do you think a nitrous motor makes more power than a turbo motor?

 

scooby i did a compression check on my motor today it has lost 100lbs. of cranking compression. would wore out rings do that or would it be a value not sealing up?

 

dsmike, I'm estimating a leakdown of around 30%. I leakdown test would tell you where the leak is. You could have a broken ring, but I'd expect blow-by or oil burning/blue smoke. If the head was no longer sealing perfectly, this might explain the lower cranking compression, but I'd expect coolant blowing out of radiator cap at full throttle. With the motor 100% cold, if you remove the radiator cap slowly and listen for air escaping, if you hear any air escape (and see coolant level down a little in the radiator) the head probably is leaking. 30% leakdown sounds like a lot for worn rings on a 4-stroke. You could try adding a LITTLE oil to the cylinder and repeat comprerssion test. If there is a dramatic change it is worn rings. You could have a slightly bent valve or a valve that is worn. If your not running a top-lube I highly recommend it. Alcohol is too dry to run without it.

 

i do not run any aditive with my alcohol. i will tear it down this week and see what the problem is. i don't think its a head gasket. my oil has been getting milked up really bad here latly. i hope it is just bad rings.


are you running stock values?

 

If it is getting milked up then you have a blown head gasket!

 

If he was running too rich due to colder weather, the rings could get washed down, allowing alcohol past the rings.

I use stock valves. Gary @ TVI might be able to get better valves, (503)648-1254 west coast time.

 

i have leaned it down alot but it is still doing it.


do you think that the cyclinder walls could have been washed down on 3 dyno pulls? i let it idle for awhile to warm up before we put it on there.