tooter's manifold adventure...

[4/20 NEVER FORGET]

Originally Posted by malibuguy

I work on A LOT of hondas. Most of the header outlets are 2". Even for a b18 teggy I worked on last tuesday. Dont let the small collector fool you. 2" is just about perfect for our motors. You want the exhaust gases to be at a high velocity when leaving the motor. The stronger the pulse...the stronger the vacuum behind that pulse. Thats what makes power. The larger the pipe the weaker the pulse strength would be and it will be traveling at a slower rate

Good to know. What do you think of my plan of going to 2.25" piping/cats/resonator throughout on the exhaust? It's what my old D16 civics ran and it seemed like a good size.

Also tooter, do you still have the 1.75" exhaust piping after the factory resonator still in place? It might be worth paying the small amount to have that replaced with a 2" or 2.25" back to the axle-back.

Also, I recently replaced my crank pulley with a MI crank pulley and I didn't notice much if any change in engine output. I did notice however that the car is easier to drive, matching revs and such. For having nothing but manual transmission cars my entire life, I drive my Yaris somewhat jerky. I would say I drive the car a bit smoother now as I go through the gears. Eventually I plan on getting a lightened flywheel, I've had them in multiple cars in the past and it makes a huge difference in the car.

[baseballfan416]

Originally Posted by tooter

I don't believe that the pluses outweigh the minuses in that regard, as I don't think it's a good idea to remove something from an engine that provides the useful purpose of absorbing crankshaft vibrations.

If it's a horrible idea, why did Garm spend R&D building them?

[tooter]

Originally Posted by baseballfan416

If it's a horrible idea, why did Garm spend R&D building them?

I didn't say it's "horrible"... you said that. I only said that there are pluses and minuses for each pulley. Each Yaris owner chooses for themselves which part best meets their needs and wants.

When each cylinder chamber fires the force is transmitted through the piston down the connecting rod to the crankshaft. This force is not applied smoothly, but is a series of pushes.

So when the crankshaft rotates from the cylinder pulses, the rubber connecting ring between the center of the pulley and the outer section allows the center to alternately rotate momentarily faster and slower than inertial weight of the outer section which rotates more smoothly. This helps to absorb the crank vibrations to make the engine run smoother.

In high performance engines under racing conditions, this is not a consideration. So parts are engineered to meet high performance racing oriented priorities.

[why?]

except that is not the case. That was the case in the 60's, and is still the case today in some larger v-8's, but it is in no way the case in a modern 4 cylinder engine.

Have you taken a look at the Yaris' pulley? There is basically no rubber on it at all. A modern 4 cylinder engine is balanced internally, that is the engine itself is harmonically balanced, and it does not need external harmonic dampeners of any type.

how many millions of problem free miles do aftermarket pulleys need for this talk to finally be buried like the falsity it is?

[tooter]

Originally Posted by why?

except that is not the case. That was the case in the 60's, and is still the case today in some larger v-8's, but it is in no way the case in a modern 4 cylinder engine.

Have you taken a look at the Yaris' pulley? There is basically no rubber on it at all. A modern 4 cylinder engine is balanced internally, that is the engine itself is harmonically balanced, and it does not need external harmonic dampeners of any type.

how many millions of problem free miles do aftermarket pulleys need for this talk to finally be buried like the falsity it is?

Thanks for the info, why.

I didn't know that the stock Yaris pulley was solid metal. So then it doesn't matter what you run.

[Golddeenoh]

a popular 4 cylinder factory balancing technique is to use balance shafts the are driven by the timing chain and turn in the opposite direction of the crank shaft. I'am not aware of any newer 4 cylinder engine that require external crank shaft dampening.

I'm with Why, there is no dampener pulleys on new age 4 cylinder engines.

[tooter]

Originally Posted by Golddeenoh

a popular 4 cylinder factory balancing technique is to use balance shafts the are driven by the timing chain and turn in the opposite direction of the crank shaft. I'am not aware of any newer 4 cylinder engine that require external crank shaft dampening.

I'm with Why, there is no dampener pulleys on new age 4 cylinder engines.

Tell you the truth, I've never looked closely at mine to see whether or not it had any rubber in it. I believe that my 4 stroke single cylinder motorcycle has a counter rotating balancing shaft because it runs pretty smooth for a one lunger that only fires once every other rotation.

Now you guys got me all curious, so I took an inspection mirror and actually looked at my pulley. It's got a rubber dampening strip in it. Maybe the 2012's are third gen that they have them now. I also found a pic of one like mine. It looks exactly like this...

[malibuguy]

having a crank damper has nothing to do with internal balance. The crank actually deflects...especially at higher RPMs & high power outputs. doesnt matter if is a old domestic motor or a k20a in a honda.

without typing out a huge thing about this subject ( I used to work for ATI Racing years ago, who makes the best crank dampers) Most lower output economy motors dont really feature a real crank damper, but rather an accessory damper.

4/20 i made good power (107/104) with a weapon*r header & my own full 2" mandrel-bent exhaust which seems to be a great match for our motor. 2.25" would most likely shift the power band upwards, but with minimal gain. I would test on mine, but Im working on a turbo kit now.

[tooter]

Originally Posted by malibuguy

having a crank damper has nothing to do with internal balance. The crank actually deflects...especially at higher RPMs & high power outputs. doesnt matter if is a old domestic motor or a k20a in a honda.

without typing out a huge thing about this subject ( I used to work for ATI Racing years ago, who makes the best crank dampers) Most lower output economy motors dont really feature a real crank damper, but rather an accessory damper.

Now that's a damper...

[Bluevitz-rs]

Either way you go is up to you but I've seen the stock pulley fail on a corolla where the rubber separated from the outer ring and left my friend stranded on the side of the road. A solid pulley will never fail. I'm sure the rubbers only there to lessen vibration to the belt driven accessories anyway. I've had mine for well over 100,000 km to no ill effect.

[Kaotic Lazagna]

Originally Posted by malibuguy

having a crank damper has nothing to do with internal balance. The crank actually deflects...especially at higher RPMs & high power outputs. doesnt matter if is a old domestic motor or a k20a in a honda.

without typing out a huge thing about this subject ( I used to work for ATI Racing years ago, who makes the best crank dampers) Most lower output economy motors dont really feature a real crank damper, but rather an accessory damper.

4/20 i made good power (107/104) with a weapon*r header & my own full 2" mandrel-bent exhaust which seems to be a great match for our motor. 2.25" would most likely shift the power band upwards, but with minimal gain. I would test on mine, but Im working on a turbo kit now.

Yeah, I have a 2.25" (crush bent) resonator back on my sedan, and it pushed the torque up past 3,500 rpm, where I'm rarely ever at. With how my car is (that exhaust, K&N sri, NST CR-Lite crank pulley, and my heavy rim/tire combo), it really feels like I have turbo lag up until I pass that point. I want my torque back down lower

[Kaotic Lazagna]

But in no way am I saying my car is gutless, I've surprised some of my friends with having a total of 4 people in my car. LOL

[malibuguy]

^ buy my old exhaust from antho ;) hes selling it cheap

[cali yaris]

Setting the record straight:

1. The Yaris stock pulley DOES have a small rubber damping strip.
2. Straight from a Toyota engineer: "The purpose is to reduce noise in the cabin ONLY; it has nothing whatsoever to do with engine longevity".
3. Conclusion: An aftermarket pulley might cause a bit more cabin noise/vibration, but that is all.
4. #3 is proven by the hundreds of aftermarket Yaris pulleys out there with not one provable engine failure or shred of evidence that a solid pulley causes damage on this car.
5. This has all been covered over and over again on this forum and many others -- anyone bothering to do a search first wouldn't need to rehash the argument, at least in reference to the Yaris.

Are we good now?

[Kaotic Lazagna]

Originally Posted by malibuguy

^ buy my old exhaust from antho ;) hes selling it cheap

I'd love to since that's one of the best sounding exhausts on a Yaris I've heard. But, any extra cash (which is 0 right now) I have will have to go towards camera gear (camera gear can make me money, whereas modding my car eaets my money ).

[malibuguy]

cant have ying without the yang ;)

[Kaotic Lazagna]

Originally Posted by malibuguy

cant have ying without the yang ;)

lol, once I get some paying gigs, I'll have some extra cash for other hobbies

[Flipper_1938]

Originally Posted by cali yaris

Setting the record straight:

1. The Yaris stock pulley DOES have a small rubber damping strip.
2. Straight from a Toyota engineer: "The purpose is to reduce noise in the cabin ONLY; it has nothing whatsoever to do with engine longevity".
3. Conclusion: An aftermarket pulley might cause a bit more cabin noise/vibration, but that is all.
4. #3 is proven by the hundreds of aftermarket Yaris pulleys out there with not one provable engine failure or shred of evidence that a solid pulley causes damage on this car.
5. This has all been covered over and over again on this forum and many others -- anyone bothering to do a search first wouldn't need to rehash the argument, at least in reference to the Yaris.

Are we good now?

They didn't do a damn thing else to reduce cabin noise....why'd they pick the crank hub to sound deaden?