Rod Punched Out The Side Of The Block

[turbotrana]

Ford may determine warranty when they strip the mtr. For example if one of the rod bolts undid itself it is easy to determine and would be a warranty job. You can usually see if detonation was a factor by examining plugs, tops of pistons and rods. Then the tune may be a factor.

Someone way back did have a rod bolt come lose on a modified T and Ford did honour their warranty

But there is certainly nothing wrong with these engines. If all done right they can cop alot.

[philldub]

Ford can tell if your car has had an edit and poor tune,theres a broken conrod out the side of the engine as proof.Unless there is a rod bolt nut sitting in the sump the rod failed cause of cylinder pressure and they no it. it appears that lots of boost is only one of the cause's of high cylinder pressure. take a look at the cylinder pressure spike cause by pinging in this ba engine.

This is from the tec section on the nizpro forum

Over the last week we have had the engine dyno running with an xr6 engine testing cylinder pressure with pressure sensors and knock sensor.This has been a development exercise for a friend of mine who makes Knock Boxes for sale to the auto industry. I will soon post a short clip of what happens when looking inside a cylinder while combustion takes place. You will be able to see the spark plug firing,cylinder pressure rising and then detonation, and how high the cylinder pressure rises. With this insight you will quickly understand why a poorly tuned XR6T engine can pop its conrods out,when they can already be close to failure when power levels are increased Stay tuned.

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Proprietor

Nizpro Turbocharging

Bayswater Victoria.

(03) - 9761 1522

Detonation is commonly refer ed to as pinging or pinking sometimes rattling or pre ignition I will try to give a very good explanation once I post the video. Don't get to embarrassed about asking questions. I am still learning about combustion it is very complex and understood fully by very few.

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Proprietor

Nizpro Turbocharging

Bayswater Victoria.

(03) - 9761 1522

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What is engine knock?

Many of us have heard the term and also witnessed the final outcome of knock related engine failures.How then might we better understand this phenomenon? How might we then guard against it happening in our expensive road or race bred engines? These are good questions.A step to getting a hold of this concept will start with an understanding of normal combustion, where knock is not evident.

To begin, we shall concentrate on the ignition phase of the 4- stroke engine cycle. I will assume you are familiar with the Otto-cycle of intake.compression, combustion and exhaust stokes common to most engines we come into daily contact with, however the general principles apply to 2- stroke engines as well.

At the point of ignition, the mixture or fuel and air has been compressed by the compression stoke to a point where it can be efficiently ignited, usually be a single spark at just the right time. When the spark ignites the mixture, it normally causes the propagation of a flame front that moves like a ripple of a stone across a pond, to envelop all of the fuel air mixture in the clearance at the top of the piston.

The key here is the orderly nature of flame propagation. It is not an explosion, which is a instant uncontrolled event. On the contray, it is orderly and progressive, starting at one place [the spark gap] and preceding until all the mixture is burnt. This takes a finite amount of time. In order to extract the most amount of work[power output] from each combustion event, the ignition is advanced to a number of degrees before top dead centra to account for this delay. Exactly how many degrees of advanced before TDC for optimum power will depend on many factors, but the dominant one will be engine speed.As a [fixed] burn time,at high engine speeds, the ignition will have to be more advanced than at low engine speeds, all other factors being equal. There is lots more to that story as we shall find out, however the extent of this explanation shall do for now.

Remember now, how we talked about the orderliness of the combustion event? This is the crucial factor. The ready-to-burn mixture is ideally in a state of turbulence for good mixing and then when the spark sets it off; most of the combustion takes place away from the metal parts. In an optimum world, only a smallish proportion of heat of combustion finds it way to the cylinder walls and other metal components such as the cylinder head chamber, piston crown or the valves and it dose this where the burning gas touches the metal surfaces.[Remember this point] You see the flame front has a cushion of non burnt gas traveling in front of it and this shields the metal surface for the majority of the time,insulation so to speak.

So stable controlled combustion minimizes heat loss to the water jackets and allows the metal components to live without stress. This leaves a significant proportion of heat left over to do what we want, and that is to expand the intake gas by making it hot and pressurized. Simple enough. The hot gas can then only become expanded when the piston moves down the bore, generating mechanical work and turning the crankshaft ,and this wins you the race.The hot gas becomes cooler as it expands and the energy lost to the gas comes out at about 30% in exhaust heat some of this is also noise, 30% in the water jacket, and 30%remaining energy to turn the crankshaft to push you forward and to prepare other cylinders on the crankshaft to fire [Mechanical loss]

So what of knock then? In simple turns knock occurs when the orderly combustion process breaks down. It turns out the most hydrocarbon fuels have a distinct limits of pressure and temperature at which they will sustain orderly combustion. What happens when these limits are reached is that the fuel mixture will self ignite [a bit like a diesel] so that there are pockets of self-ignition combustion distinct from the spark originated combustion.

This causes considerable dis array in the combustion event. The combustion is no longer orderly and stable. It often happens that a particular part of the combustion chamber will trigger a separate self- ignited flame front. This causes a localized pressure event that pushes or distorts the remaining un-burnt mixture with such force it will wobble backward and forwards in the combustion chamber and make the combustion chamber ring like a bell for an instant. While that ringing or washing backwards and forwards is happening, of course the mixture is continuing to burn. This causes the burning mixture to contact much more of the surrounding metal parts than it would normally do [more surface area is exposed] and so it imparts far more heat into those metal surfaces. What the result is a kind of runaway process. The super-hot components[valve edge,squish nose,poorly cooled patch of chamber floor and piston crown] will then likely cause another unstable event,and that will add even more heat to these susceptible areas and before long, pinging/knock/detonation becomes the rule and engine destruction becomes inevitable if left without something drastic being done.. Other knock causes are related to temperature such as exhaust gas contamination. Here the exhaust back pressure can return into the cylinder on valve overlap and kick off premature ignition, causing Knock. However poor cooling around the combustion chamber or high inlet charge are often other causes of knock.

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Proprietor

Nizpro Turbocharging

Bayswater Victoria.

(03) - 9761 1522

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Ok here are some snap shots and some pressure profiles

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NoEngineKnock.JPG

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Proprietor

Nizpro Turbocharging

Bayswater Victoria.

(03) - 9761 1522

Bugged if I no I cant copy the preesure profile,but you should go have a look ,picture paints a 1000 words

[Adam]

I've done a bit of cleaning in this thread.

Vik, it's clear that Tab doesn't like you attacking him so please stop it. There are others that can appreciate your strange sense of humour but Tab is not one of them.

Can we please keep this thread somewhere near the original topic.

Thanks guys,

Adam.

[hrb93]

THe XR6t has the best turbo ever bolted to a production engine.

Without the turbo on it, it would n't even rate in the top 500 engines ever made.

If you want a bullet proof bottom end as well as box, get a 2j, 1000hp on a stock motor.

[C.S.I]

if you go to your dealer and they install a "newer ford flash" and you go home and "flash in your modded tune" I was under the impression that you would now be dowloading the "new ford flash" to your flash unit prior to uploading your modded tune, hence next time you go for service and flash it back to standard, it would now have the "new ford flash" that was installed at you last service hence not create any suspicion at the dealer. Tell me if I am wrong.

<{POST_SNAPBACK}>

Ok, Your wrong :-)

The CAPA Edit boxonly ever Downloads ONCE the Ford Factory tune. (and that's the 1st time its plugged in and used)

After that, it will only UPLOAD (from CAPA Box to car) 1 of the 3 Installed tunes, or the Original F (Factory) tune.

Flashing your car back to stock from the F slot does NOT erase the Factory tune from the Flasher BOX. Its there forever, unless reset/cleared by a CAPA rep.

You would need to get the CAPA Flasher reset by a Tuner to get the F slot cleared.

Alan

[BAturb]

so when do you use one of the 5 lives in the box? and what happens to the factory tune when you buy a new car and flash the new car with the same box? what happens to the tune in F slot?

[Guest newl]

When you get a new car, you get your tuner to reset the box for you because it'd be VIN locked to your first car. After it's reset, it'll download the factory tune from the new car as it did on the old and then be locked to the new VIN.

[summoner]

THe XR6t has the best turbo ever bolted to a production engine.

Without the turbo on it, it would n't even rate in the top 500 engines ever made.

If you want a bullet proof bottom end as well as box, get a 2j, 1000hp on a stock motor.

<{POST_SNAPBACK}>

Actually yes it would rate within the top 500 engines ever made. While the 2JZ is a great engine they will f*ck up just as bad as this 1 did from bad tuning. The Barra has alot of potential and I see it more of the RB26 of the Domestic market. No-one has and I doubt will develope a 2jz style engine again for a very long time.