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Nice! Thanks for posting that. Stainless exhaust eh? Who knew? Actually, I don't think the muffler and tailpipe is, instead just the piece from the 3rd cat back.
I agree with his assessment of the fuel tank protection too. Odd that Honda only protect part of the tank. Didn't someone find an NHSTA report on another thread about a punctured gas tank?
 

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Thanks Spritegeezer for finding the article; I appreciate the ROC and all the members looking out for each other. Each article posted makes love my RL even more. Is there any bad press out there?
 

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Lingered_I said:
Nice! Thanks for posting that. Stainless exhaust eh? Who knew? Actually, I don't think the muffler and tailpipe is, instead just the piece from the 3rd cat back.
I agree with his assessment of the fuel tank protection too. Odd that Honda only protect part of the tank. Didn't someone find an NHSTA report on another thread about a punctured gas tank?
Yes here is the original post:

http://www.ridgelineownersclub.com/forums/showpost.php?p=48425&postcount=139
 

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Quote from that site:
This is the same truck we did ALL our testing with, including off-road. We shot this video late in testing, so what you're seeing is the after effects of off-roading. Notice any dings, scratches, etc.? Neither did we. =-)

Ryan
The bottom looks brand new, like it never was on the road before. Never mind that it went through a "off- road" test.
Quite an impressive article -- great find.;)
 

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Here is some info that I found online..I believe Hona engineers know what they are doing:)
Is Bigger Better or is Faster Best?

When contemplating a modified exhaust system there are those who want the biggest diameter pipe that can be had. Their idea must be that fatter pipes are more effective at venting than narrower pipes. This sounds reasonable but it is not quite correct. Sure wider pipes have greater volume and higher flow capacity, but that is just half of the story. Capacity is one consideration but gas velocity is the other factor.
An experienced exhaust designer knows that the best exhaust is one that balances flow capacity with velocity. A given volume/time of gasses will travel faster through a 2" pipe than the same volume of gas passing through a 3" pipe. So when taken to its extremes we can see that a too narrow pipe will create backpressure (restrictions to positive flow) problems and a too wide pipe will cause a very slow flow with no backpressure.
The optimum is where the fastest velocity is achieved with the least constriction possible.

This situation will arise when the pipe is wide enough so that there is the least level of positive backpressure possible whilst achieving the highest exhaust gas velocity.
The faster the exhaust gas pulse moves, the better it can scavenge out all of the spent gasses during valve overlap. The scavenge effect can be visualised by imagining the high-pressure pulse with a trailing low-pressure area behind. The faster the high-pressure pulse moves the stronger the draw on the low-pressure gasses and the gasses behind that. The scavenge action is like (but not exactly) suction on the gasses behind.

The greater the clearance burned fuel from the combustion chamber the less diluted the incoming air/fuel mix is. Scavenging can also aid intake on overlapping valves (where the exhaust and inlet valves are open at the same time) by drawing in the intake. These are good things to happen.

So instead of going for the widest pipe possible we should be looking for the combination of the narrowest pipe that produces the least backpressure possible. In this scenario we achieve the least restriction on positive flow and the highest gas travel speed.

Exhaust pipe diameters are best suited to a particular RPM range. If we used a constant RPM engine this would be easy to specify. But a variable RPM engine will mean that not one size suits all. It is possible to vary the size of exhaust volumes according to rpm but it is very expensive (Ferrari has done it). The optimum gas flows (volume and speed) are required at the RPM range that you want your power band to be located. For a given engine configuration a small pipe diameter will produce higher exhaust velocities at a low RPM (good) but create unacceptably high amounts (bad) of backpressure at high rpm. If you had a car with a low RPM power band (2,000-3,000 RPM) you would want a narrower pipe than if your power band is located at 5,000-7,000 RPM.
 

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Awesome find there Spritegeezer, Thanks for finding this! and Happy holidays too..
 

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Great education video for almost mechanics like myself. Interesting follow up on exhaust size also from another member. Great work guys.
 
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