How to ruin your day
- Thread starter CFulton89
- Start date
Now to start over mmr stroker kit and new ford racing block
Nothing wrong with the block. Maybe don't go over 450rwhp on stock internals, and they won't punch a hole when they explode? That MMR set up will probably do the same thing lol.
Ouch! How much power were you making? I thought the stock bottom end could handle around 425-450 hp or so?
464hp. The mmr kit with Kellogg crank is rated for 1000hp it better not explode. The stock internals are a ticking time bomb.
It's got nothing to do with what they're rated to. Just as long as they don't build it, you should be fine.
Whoever is willingly letting you push that much power on factory internals and that kind of compression of a stock cobra engine is one brave tuner. Obviously you're making well past what many people say these stock internals can handle, I'm not sure why you're surprised by all of this.
I not surprised. Just hard headed. I plan on 6-700 hp. It had 8.5:1 cpr btw
When you are seeing piston crown and ring land failures like that, It's not about how much horsepower you're running, rather how much boosted air you're trying to force into the combustion chamber. Now, that's a little counter-intuitive, because the best way to make horsepower is to cram more air, but it's not a true horsepower that will kill Pistons. When you are talking about parts that are horsepower limited, you are talking about parts that experience extreme torsional forces. You know that you are having horsepower related failures when you see roaring bending fatigue fractures running diagonally across the length and width of your crank journals. That is the sign of an overloaded crank.
Whoa there...slow down new guy, you are making sense lol
Fact is the the op most likely got greedy. Even a build bottom end will fail with a bad tune, lean condition, broken oil pump gear, etc etc etc etc etc et .
When was the last time you drove your Cobra?
A over loaded crank? The crank is not what failed. Your post sounds loaded with knowledge but lacks real info. Big 50 cent words but is just 2 cent worth of what.? Not really wanting to be rude or a dick but do wantt to know what the hell you are trying to say. help the dumb here please.
Thursday...she saw 9.5 indicated and 6800 rpms too
Ive put over 40k on if since the blower and i have well over 100 passes at the track with it. Some in 95f florida heat and others in 40f north pa evenings. All on plain old pump gas 93oct
Tune is key man
That was in response to the posters asking how much horsepower he was running. I was simply trying to point out that that engine should have and could have handled the horsepower, and that the broken Pistons indicated over pressurization in the combustion chamber. What I was saying about the crank, was that if it had truly been a horsepower overload, that would have failed.
Detonation is what happened plain and simple...that is what caused what you decribed as "over pressurization"
Could have resulted from too much timing, injector failure, fuel delivery issue, etc etc...but im betting on too much timing and a lean af in the search of more power
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I think we both agree that he got too greedy with the boost on the cast Pistons. Even with a good tune and no detonation, he would have experienced a failure sooner or later. Also, I would have to believe that the knock sensors would have retarded the timing if he had bad enough detonation to cause that kind of fracture...
I was just giving you crap. I remember you were letting it sit for other hobbies.
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