3star2nr
Well-Known Member
- Thread starter
- #1
Warning: long read...
"Cheap. Reliable. Fast. You can only have 2 of the 3. Pick your poison."
This is the iron law of tunning people who don't get this are in for a fucked up day...
I give you exhibit A:
Now before you make fun of him, or dodge the truth is his experience is far too common and can happen to anyone... His specific engine failure is actually very common. And regardless of brand all cars are essentially the same and usually fail for the same reasons...
People watch YouTube, go to car meets and read blogs and think it's "easy" to build a "9sec daily driver".
The truth is its NOT easy, and the people who succeed often have a long trail of blown motors and transmissions behind them. Yes the manufacturers have stepped up and have built us amazing motors, so the "cost" to get into the 9 sec club seems cheaper than ever. But its an illusion... the iron law still stands.
I'll disect this video as a case study of what can go wrong so hopefully you dont make the same mistakes. My goal is for people to avoid alot of heartaches by being better prepared and approach tunning in a different way.
0. Engine failure is very rarely caused by "one thing" it's usually caused by a sequence of issues that add up to failure. We have a tendency to fixate on the one broken part and often this leads to misdiagnosis of the problem, and causes us to fail again...
In my opinion His specific failure was caused by a combination of factors:
1. Fuel:
A. Use the correct fuel. The guy in this video was running 900 whp using only boostane... As you can see from his motor there is a ton of varnish build up. This is because addatives like boostane were NEVER intended to be used as a permanent fuel solution... If you cannot afford or have access to the proper fuel for your application build your car to run on pump gas.
B. Monitor fuel pressure.
He suspects that the OEM fuel rails is the problem, while they certainly dont help the issue they werent the cause in and of themself. The fuel system is a pressurized system so once the system is pressurized and functioning properly all injectors should see the same pressure and fuel.
It's important to log fuel pressure and be aware of pressure drops because this can cause the engines to run lean...
It's also important to maintain a full tank of gas. Not only does this help fight sloshing and reduce pressure drops in the rails, Low fuel also causes fuel pumps to overheat, that heat has to go somewhere right... The logical place is to your fuel... Which compounds issue 2.
2. Understand heat. Cylinder 7 is usually the cylinder that will blow on 99% of V8 engines... This isn't rocket science its because of heat...
Most cars cooling systems has the water pump feeding cylinder 1. The coolant flows through the water jackets around the cylinders absorb heat then to the radiator to dissipate it... Since cylinder 7 is at the rear of the motor it's the last one to recieve oil and coolant, this causes this cylinder to run hotter than all the others and in most cases will be the most sensative to detonation,
This is also true in V6 and 4 cylinder engines.
Ford on the aluminator engines added extra cooling lines to help fight this issue. To the best of my knowledge our coyotes never got this neither did the gt350s.
This was an addition specifically for their racing engines. Heat is your number 1 enemy both stock and in tunning and is also the thing everyone glances over...
Changing the radiator and thermostat may not be enough for your specific application.
So you need to monitor your cylinder temp, at the build phase, And make sure that your cooling system is keeping up. There are mods you can do to improve circulation in your motor, and the more heat you can take out of the engine bay the better. You can do this by, upgrading your fans, running larger lines, installing a header heat shield etc.
Using a ir thermometer to monitor temps on a dyno during the pull may not be a bad idea. Or taking before and after readings after a few pulls and hard driving. Remember your cooling system was designed for stock power levels and driving. And your cooling system is just that a system of parts not just a radiator and thermostat...
3. Choose the right parts. This is the number 1 thing to take from all this... There is a HUGE DIFFERENCE in parts designed for racing and parts designed for street, performance applications. In this video he has a mcleod RXT clutch. He is shocked and dissapointed to find that the clutch he just bought is almost toast...
Reality is the RXT is a full on racing clutch. It's designed to survive 1 racing season at most... Not designed for a street car application. Racing clutches prioriterizes clamping loads over, reliability, driveline protection and comfort.
If You have a 250k drag car with millions in sponsorship money on the line then you need a clutch that will hold and take you down the track. Then during the winter you replace the clutch. That's how these clutches are intended to be used... Most racing clutches will last less than 1 year of street driving... The clutch was wearing exactly as it should. He just made a poor choice... Now mcleod is getting an unfairly earned bad reputation.
4. Build it right or build it twice. After an engine failure ALWAYS get your fuel injectors cleaned and flowbenched, or replace them.
I suspect the buildup from the boostane could have been a contributing factor to this engines failure. But without testing there is no WAY to know for sure. Also be careful buying used injectors... Especially with modern engines proper fuelling is critical.
After a failure rebuild your supercharger or turbos, or send them to a professional to be thoroughly cleaned and rebuilt if necessary.
Replace all coolant and oil lines, and heat exchangers... You don't want a piece of a piston blowing up your new motor... This happens very often.
So to summerize there is no shortcut to power, and even when you do everything right it's just the nature of the beast that parts will fail...
Even F1 Teams with the best engineers and mechanics on the planet still struggle with reliabilty issues. High power engines are extremely delicate, the more power you make the more delicate the engine becomes. Make the right choices and be realistic with your goals...
Not because You can buy a cheap craigslist blower... mean you should. Take an honest look at your situation, and plan before you pick up a wrench.
Always assume The absolute worst thing will happen, and have a plan for that before you start, because 90% of the time that will be the result.
"Cheap. Reliable. Fast. You can only have 2 of the 3. Pick your poison."
This is the iron law of tunning people who don't get this are in for a fucked up day...
I give you exhibit A:
Now before you make fun of him, or dodge the truth is his experience is far too common and can happen to anyone... His specific engine failure is actually very common. And regardless of brand all cars are essentially the same and usually fail for the same reasons...
People watch YouTube, go to car meets and read blogs and think it's "easy" to build a "9sec daily driver".
The truth is its NOT easy, and the people who succeed often have a long trail of blown motors and transmissions behind them. Yes the manufacturers have stepped up and have built us amazing motors, so the "cost" to get into the 9 sec club seems cheaper than ever. But its an illusion... the iron law still stands.
I'll disect this video as a case study of what can go wrong so hopefully you dont make the same mistakes. My goal is for people to avoid alot of heartaches by being better prepared and approach tunning in a different way.
0. Engine failure is very rarely caused by "one thing" it's usually caused by a sequence of issues that add up to failure. We have a tendency to fixate on the one broken part and often this leads to misdiagnosis of the problem, and causes us to fail again...
In my opinion His specific failure was caused by a combination of factors:
1. Fuel:
A. Use the correct fuel. The guy in this video was running 900 whp using only boostane... As you can see from his motor there is a ton of varnish build up. This is because addatives like boostane were NEVER intended to be used as a permanent fuel solution... If you cannot afford or have access to the proper fuel for your application build your car to run on pump gas.
B. Monitor fuel pressure.
He suspects that the OEM fuel rails is the problem, while they certainly dont help the issue they werent the cause in and of themself. The fuel system is a pressurized system so once the system is pressurized and functioning properly all injectors should see the same pressure and fuel.
It's important to log fuel pressure and be aware of pressure drops because this can cause the engines to run lean...
It's also important to maintain a full tank of gas. Not only does this help fight sloshing and reduce pressure drops in the rails, Low fuel also causes fuel pumps to overheat, that heat has to go somewhere right... The logical place is to your fuel... Which compounds issue 2.
2. Understand heat. Cylinder 7 is usually the cylinder that will blow on 99% of V8 engines... This isn't rocket science its because of heat...
Most cars cooling systems has the water pump feeding cylinder 1. The coolant flows through the water jackets around the cylinders absorb heat then to the radiator to dissipate it... Since cylinder 7 is at the rear of the motor it's the last one to recieve oil and coolant, this causes this cylinder to run hotter than all the others and in most cases will be the most sensative to detonation,
This is also true in V6 and 4 cylinder engines.
Ford on the aluminator engines added extra cooling lines to help fight this issue. To the best of my knowledge our coyotes never got this neither did the gt350s.
This was an addition specifically for their racing engines. Heat is your number 1 enemy both stock and in tunning and is also the thing everyone glances over...
Changing the radiator and thermostat may not be enough for your specific application.
So you need to monitor your cylinder temp, at the build phase, And make sure that your cooling system is keeping up. There are mods you can do to improve circulation in your motor, and the more heat you can take out of the engine bay the better. You can do this by, upgrading your fans, running larger lines, installing a header heat shield etc.
Using a ir thermometer to monitor temps on a dyno during the pull may not be a bad idea. Or taking before and after readings after a few pulls and hard driving. Remember your cooling system was designed for stock power levels and driving. And your cooling system is just that a system of parts not just a radiator and thermostat...
3. Choose the right parts. This is the number 1 thing to take from all this... There is a HUGE DIFFERENCE in parts designed for racing and parts designed for street, performance applications. In this video he has a mcleod RXT clutch. He is shocked and dissapointed to find that the clutch he just bought is almost toast...
Reality is the RXT is a full on racing clutch. It's designed to survive 1 racing season at most... Not designed for a street car application. Racing clutches prioriterizes clamping loads over, reliability, driveline protection and comfort.
If You have a 250k drag car with millions in sponsorship money on the line then you need a clutch that will hold and take you down the track. Then during the winter you replace the clutch. That's how these clutches are intended to be used... Most racing clutches will last less than 1 year of street driving... The clutch was wearing exactly as it should. He just made a poor choice... Now mcleod is getting an unfairly earned bad reputation.
4. Build it right or build it twice. After an engine failure ALWAYS get your fuel injectors cleaned and flowbenched, or replace them.
I suspect the buildup from the boostane could have been a contributing factor to this engines failure. But without testing there is no WAY to know for sure. Also be careful buying used injectors... Especially with modern engines proper fuelling is critical.
After a failure rebuild your supercharger or turbos, or send them to a professional to be thoroughly cleaned and rebuilt if necessary.
Replace all coolant and oil lines, and heat exchangers... You don't want a piece of a piston blowing up your new motor... This happens very often.
So to summerize there is no shortcut to power, and even when you do everything right it's just the nature of the beast that parts will fail...
Even F1 Teams with the best engineers and mechanics on the planet still struggle with reliabilty issues. High power engines are extremely delicate, the more power you make the more delicate the engine becomes. Make the right choices and be realistic with your goals...
Not because You can buy a cheap craigslist blower... mean you should. Take an honest look at your situation, and plan before you pick up a wrench.
Always assume The absolute worst thing will happen, and have a plan for that before you start, because 90% of the time that will be the result.
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