I'm surprised you can keep the head gasket sealed
With high strength head bolts I had air getting past the gasket into the cooling system in the low to mid 20 range when my controller screwed up.
To much Boost !!!!!!!!!
- Thread starter West Coast Sleds
- Start date
I'm surprised you can keep the head gasket sealed
With high strength head bolts I had air getting past the gasket into the cooling system in the low to mid 20 range when my controller screwed up.
Had the same issue on stock head bolts, twice in fact, tore the head down so many times looking for exhaust gas leaks around the head that the cam carrier bolt holes started to strip out. That = new head. I now run with head studs.
I'm surprised you can keep the head gasket sealed
J
JSCC
Well-known member
I wonder though how much elevation plays a role in that....
20lbs at 5,000' is not the same as 20lbs at 10,000, so at what point I guess do they cross? Do you know what I mean?
Those of us that ride high altitude get away with alot more than those running lower, so I wonder at what point do all these things really start to effect us. And do any of us really run that much boost on a consistant basis?
20lbs at 5,000' is not the same as 20lbs at 10,000, so at what point I guess do they cross? Do you know what I mean?
Those of us that ride high altitude get away with alot more than those running lower, so I wonder at what point do all these things really start to effect us. And do any of us really run that much boost on a consistant basis?
atmospheric pressure is 14.7 at sea level and you lose about 3% per 1000 ft. so about 5 psi at 10,000 ft. so if you were running 15lbs at sea level you would have to run about 20 lbs at 10,000 ft. to make the same power, due to the loss of atmospheric pressure. a motor doesn,t know the difference between atmospheric pressure and boost pressure. 14.7+15=29.7 , sea level, 20+ 9.7 roughly at 10,000 ft. =29.7
u can run 20psi on the stock nytro but u need the propper box one that adds fuel and allows u to pull and add timing that is why ur fuel is so crucial to compensate for the pre ign.(DET) but if u can pull the timing back and add fuel u can actually run premium. aka Rapid Bike 3
p.s Don't understand, too bad, enjoy rebuilding motors...
p.s Don't understand, too bad, enjoy rebuilding motors...
I usually do not respond to snide remarks but guru of the boost why don't you enlighten us on how you think the stock nytro motor can handle 20 lbs of boost even with timing pulled. I don't mean for 1 day I mean for a season. For example how do the stock injectors handle enough fuel to run 20 lbs? How do you run premium at 20 lbs under high stock compression? Perhaps I can stop wasting money on fuel.
if you are trying to say you can run 20 lbs on a totally stock motor on pump fuel at sea level, just by pulling timing, enjoy rebiulding your motor. if you can pull enough timing to make it last you won,t have enough hp. to make it worth it. and I have ran stock motor at 22lbs and a 30 shot of nitrous at 10,000 ft with good fuel and no timing pulled all year, but you won,t do it on pump fuel.
i personally would not run pump fuel good gas is cheap insurance. my point is that u can't just put rods and pistons in a motor and expect to make more power with more boost. it will actually make the same or less. boost is compression.
yes u can run high boost on pump fuel 15psi sea level timing pulled 20 psi at 7500ft timing pulled but a nytro at 15psi no timing pulled at 7500 on straight av gas pulled way harder. and in my opinion would last the longest.
ps.sorry didn't mean to be snide
pps if ur turbo manufacturer says run a max of 15psi run it don't try and push it.. And try and enjoy the rest of the year sledding rules!!!!!
yes u can run high boost on pump fuel 15psi sea level timing pulled 20 psi at 7500ft timing pulled but a nytro at 15psi no timing pulled at 7500 on straight av gas pulled way harder. and in my opinion would last the longest.
ps.sorry didn't mean to be snide
pps if ur turbo manufacturer says run a max of 15psi run it don't try and push it.. And try and enjoy the rest of the year sledding rules!!!!!
W
West Coast Sleds
Member
Not just doing rods & pistons, and valve springs. I was just simply looking for some feedback. I have orderd everything from dustin to safely run 15-20 lbs of boost @ 7k-10 on straight race.
BTW what controller would you suggest running??? I have the BD Box. And BD Injectors.....Or a BD Kit if you will.
D
dcturbo
Well-known member
I'd sell the BD kit and get Impulse race kit
Then you could run the pure logic box, which is simple to use.
N
NM
Well-known member
Yup, I agree. With headshim and 35 lb ft tourque the limit seems to be about 17-18 lbs before air starts to displace the coolant.I'm surprised you can keep the head gasket sealed
With studs and 55 lb ft tourque it is about 20-21 lb boost max. It all comes down to cylinder pressure I guess. We are trying to find a rad cap that is rated at 20-21 lbs and hopefully fixes the problem. Factory cap is 17 lbs.
W
WesG
Well-known member
Maybe I'm on landmines but...
FWIW I have been running 20 psi @ 3-6k ft. Have all season. 38 ftlbs rings a bell when I did my head shim. No coolant loss at all. Straight c-12 for fuel. The whole system has been aheckova lot harder to keep sealed vs 15/18 lbs, but the head has never pushed coolant.
FWIW I have been running 20 psi @ 3-6k ft. Have all season. 38 ftlbs rings a bell when I did my head shim. No coolant loss at all. Straight c-12 for fuel. The whole system has been aheckova lot harder to keep sealed vs 15/18 lbs, but the head has never pushed coolant.
N
NM
Well-known member
Apex or Nytro? The Apexes don't seem to have the same problem. It is also the long hard pulls at WOT 20-40 sec.
B
BigFish BC
Well-known member
Ya its an apex. Wonder why the nytro's are having trouble... At 20 lbs there are not very many 40 sec pulls with the snow we have had this year
the longer stroke dont help 66mm on nytro vs 58 on apex.
if you guys are only torking 38 lbs on a nytro thats your problem, if you degree them like yamaha says and watch a tork wrench you will see they are 55-60 lbs, I have never had a problem with stock bolts on a nytro, and as I have posted 20+ lbs with nitrous. the key is the install, make sure everything is cleaned with acrtone head and block surface, I only use yamaha gaskets not shim, don,t touch gasket surface with your fingers and don,t put anything on them, make sure they have the factory black coating on both sides, and use the stock tork proceedure and you shouldn,t have any problems.
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W
West Coast Sleds
Member
Another ???
I thought I have been loosing coolant and getting hot before this happend. If I were looseing coolant would I see it in the oil?? If not I probably lost the head gasket at the end of last season. I couldnt get this bitc* to run right at all this year!
Very good lesson learned on this project.
I thought I have been loosing coolant and getting hot before this happend. If I were looseing coolant would I see it in the oil?? If not I probably lost the head gasket at the end of last season. I couldnt get this bitc* to run right at all this year!
Very good lesson learned on this project.
J
JSCC
Well-known member
I'd sell the BD kit and get Impulse race kit
He could run the Pure Logic box on the Bd kit. But simple does not always equate to better.
