Finally my 1st (water cooled) turbo build
#681
No it isn't, that's quite a stretch Pat. One is an airplane, one is a car. One has a proven track record of actually killing humans due to the exact nature of the issue when these considerations aren't taken into account and are probably required considerations by certain countries and organizations; the other doesn't(that is to say, planes accidents have been investigated and this issue has been verified to be a cause in some, we have 0 proof of any of this in our cars. The only thing we do have is anecdote from bob bolstering my point and disputing yours) and it isn't required.
Also I highly doubt mazda did any of the calculations, at least for the gear box side. I assume(could be wrong) that to be an incredibly difficult thing to model and get any real data out of with todays computational analysis, let alone in 1989 or before. PSRUs are uaully a drive and a driven gear or sprocket with a chain belt or whatever. Not a multi shaft, multi speed gear box. Also, it doesn't matter because we arn't talking about stock engines and drive train combinations that mazda would have modeled. Lol at you(specifically) talking about running parts that are designed to work together.
Again, my point is, that any talk of damping without knowing the transmissibility of the system is an absolute waste of time. We will probably never know that relationship. What little data points/anecdote that exists points tot he fact that is doesn't fuking matter. Im quite surprised that a data driven engineer type such as yourself has no issue throwing this idea around with such certainty, having no data for the specific case of our cars, and having read the article that makes it abundantly clear that you need the data. Even phrased as "understand this".
So, run the FW you like. If that means the stock one because it makes you feel better about your power pulses, then so be it.
Also I highly doubt mazda did any of the calculations, at least for the gear box side. I assume(could be wrong) that to be an incredibly difficult thing to model and get any real data out of with todays computational analysis, let alone in 1989 or before. PSRUs are uaully a drive and a driven gear or sprocket with a chain belt or whatever. Not a multi shaft, multi speed gear box. Also, it doesn't matter because we arn't talking about stock engines and drive train combinations that mazda would have modeled. Lol at you(specifically) talking about running parts that are designed to work together.
Again, my point is, that any talk of damping without knowing the transmissibility of the system is an absolute waste of time. We will probably never know that relationship. What little data points/anecdote that exists points tot he fact that is doesn't fuking matter. Im quite surprised that a data driven engineer type such as yourself has no issue throwing this idea around with such certainty, having no data for the specific case of our cars, and having read the article that makes it abundantly clear that you need the data. Even phrased as "understand this".
So, run the FW you like. If that means the stock one because it makes you feel better about your power pulses, then so be it.
As for data, I have run a stock and 10lb flywheel. The 10lb one had terrible gear noise at cruise and on decel. The stock flywheel is silent. That noise is caused by lighter flywheel changing the dampening of the engines torque output. So it absolutely had an affect on the system. Less weight causing more noise tells me we're on the left side of your graph, not the right side. If we were on the right side in this RPM band, less mass would have improved dampening and gear noise would be reduced, not increased.
Your argument is that because you or I have not designed and measured the entire system's response to various flywheel weights (and because Mazda has not come here to tell us what they did and show us there conclusions), we should just ignore it and use whatever we want. I don't agree with that.
#682
Your argument is that because you or I have not designed and measured the entire system's response to various flywheel weights (and because Mazda has not come here to tell us what they did and show us there conclusions), we should just ignore it and use whatever we want. I don't agree with that.
--Ian
#683
Almost every part that mazda built that has failed on my car once has been upgraded to something stronger/better. For how I use my car, that's a lot of stuff. If what they did isn't working I change it. I do leave things the way mazda did them if they still work fine for my goals and prove reliable.
#684
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But we don't know if it's working correctly. Because you don't do the kind of driving that usually breaks transmissions (max torque low down in the power band) long extended sessions. And most everyone else is running a light flywheel because it makes shifting easier and faster.
#689
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As 18psi said it depends on use. 300-350rwtq would be the range id assign to 6 speed trans breaking. 350 would be street with lots of mechanical empathy. But there is a HHHUUUGGGGEEE thread with all this info you can go read. Lets let Ryan get this back to being a build thread.
#693
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Sadly, it is currently a money sucking pit that does not move. Silly me, I thought that valve springs were going to cost me 400 bucks. Yeah right. Oh and that new manifold, yeah, it needs to be ceramic coated. So another 250 or so all said and done. Aaaaaand new 8mm inconel hardware. Then I need to fab up new hardlines for the water/oil, because new turbo. Wants lower extended ball joints. Need to pay for hybrid mounts I agreed to buy. ****.
#695
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Wow, so this car is in a lot of pieces again. New OE Mazda rear hubs on the way, engine is out, head is off. Got the new ARTech manifold coated by SwainTech. Looks amazing. Head is off and getting a re fresh along with some +1mm Inconel goodies. So naturally I had to cut the font end up a bit. Making some aero improvements. Standard 949 recipe air damn and my own custom splitter.
Figuring where exactly this splitter will go and a general shape. 1/4" plywood for easy mods and to use as a stencil for the real one. It will be a two piece unit extending to the middle of the car..I think.
Anyhoo, here is a pic of the air dam in its current state. Splitter should be about 3.5 inches off the ground with a 4.25 pinch weld ride height, gradually sloping up to the bottom of the frame rails or close to them.
Figuring where exactly this splitter will go and a general shape. 1/4" plywood for easy mods and to use as a stencil for the real one. It will be a two piece unit extending to the middle of the car..I think.
Anyhoo, here is a pic of the air dam in its current state. Splitter should be about 3.5 inches off the ground with a 4.25 pinch weld ride height, gradually sloping up to the bottom of the frame rails or close to them.