the flat housing is iron so it holds more heat?

I'll know soon enough anyhow

 

The front/middle/end plates have been iron way before the Renesis.

Cheers,
Hymee.

 

right, but they've never had exhaust running through them.

 

OK. I see where you were coming from. I'm keen to see where all this heads.

Cheers,
Hymee.

 

Now this is a student. Heat is a mother.... when its in the wrong place.

Also, why I keep an eye on his remote turbo project. Too bad about his engine though....

 

i'll ask again - in the nicest possible way

 

SS is a long time from now so if you have information that may help people in making an informed decision about what to do and what not to do to their engine, please share it.

Now that the reflashers are available more and more people are going to be trying FI. If there is possibly an issue with a certain form of FI on the Renesis that you know about, please share that information so that people can utilize it in their decision making process.

I wouldn't want someone to buy a turbo kit this summer only to find out that there is a design issue with using turbos on the Renesis. This is only an example but hopefully you get the point. I know your a good guy and hopefully you will spill the beans for the good of all 8 owners. Thanks!

 

I know that, but... And why you always talking about scandals.
I'm just asking for information that could help people make a more informed decision. Information is key and you agree that there should be no secrets. How is this any different?

 

There are plenty of people driving around in turbo RX-8s right now, so it's not that big of a deal.

 

I have reason to believe there is something to be investigated with forced induction. As of right now it is an issue that has been seen with one type of system but not another. However it is way too soon to say that it is exclusively caused by one such system. There are far too many variables out there that could have effected the results for anyone to truly say that X system is safe by Y system isn't. It's not anything that 99% of the people need to worry about anyways. It's just an issue that may or may not pop up on very high horsepower engines. The other scenario is that this one occurrance was a fluke and won't happen again. It's not worth me getting into at this time because trying to draw conclusions from a one time occurance based on the limited amount of known information is about as dumb as trying to say we are warming the planet due to higher CO2 concentrations. A true accurate correlation can't be drawn at this time and even if one could, most people will never need to worry about it. It's nothing to panic about which is why the info can wait until SS if it hasn't already gotten out there. Basically we need to see if this happens again.

 

What happened?

 

Assuming this has to do with the "overheated" exhaust ports, it's possible that it could have been a tuning issue that caused excessively high EGTs, right?

 

Here's a small hint. The Renesis rotors are wider than the 13B rotors. This isn't really a topic that needs to go any farther in an Axialflow thread anyways. A new thread could be started that could be based on speculation as it's not proven that there is in fact truly an issue. It could be a limited one time thing.

 

Well, I vote RG starts a new topic. The first thing that comes up is how effective would heat shields or heat jackets be to counter the heat problem with turbo and decreased engine life span. Then there is the emissions and cat killer issues with them.

 

uh, who runs cats with turbos?

 

Every production car built that has a turbo...

Cheers,
Hymee.

 

i meant rx8s...

 

Are you talking about how the oil metering pump functions when it sees positive pressure instead of vacuum?

This has always freaked me out.

 

I'm not going to clog up this thread with another topic anymore. It's got enough off topic pages already.

 

Happy Easter, everybody ~

 

The MOP is positive displacement. I won't care if it sees either positive or negative pressure.

 

No. A fuel injector will deliver flow according to the differential pressure across it. It has a fixed pressure on one side. If the pressure on the other side increases/decreases, the differential pressure decreases/increases and the flow will decrease/increase.

The MOP is a piston pump, analogous to the operation of a crank, connecting rod, and piston/cylinder arrangement with the crank rotated regardless of the pressure in the cylinder. If the piston gulps in some oil on the intake stroke, it will expel the same oil on the discharge. The pressure reached depends on the resistance. If the discharge is blocked, the pressure will reach very high levels, and something will either break, or the oil will be forced through the piston/cylinder clearances.

 

Yes.

With regard to the oil nozzles (I assume these are your atmospheric vent(s)), see the fourth bullet under 'Operation' in the attached file. I think I know this pump pretty well, but I can't understand their reasoning as to why these nozzles are required.

 

Given that air will be drawn in, then the pickup point makes sense. The question is - why are nozzles required at all since the only source of oil is the pump, and a vacuum on its outlet will not affect the oil flow - at least in principle.

And this may be the answer - reality that is. For example
- the piston diameters are very small, making their circumference to cross-sectional areas relatively large, so the area available for leakage is relatively large relative the volume of fluid pumped.
- the pistons are not equipped with rings or any such leakage reducing elements.
- over time, clearances will increase with wear.

The pump flow is the product of engine speed and some function of the step position of the cam that controls the piston stroke length (actually the pistons are stationary, the cylinders move). Maybe this summer I'll hook up my 'chopstick' device and determine this function, but for the moment let us assume the oil requirement at idle is very small. Also consider being stuck in traffic for several hours on a blazing hot summer afternoon with 100,000 miles on the engine.

The idling would pull a high vacuum on the pump outlet, and the clearances and low oil viscosity may be such that hours of operation could result in considerable oil being pulled through the pump, even though the PCM may dictate that very little oil actually be pumped. The by-pass in the nozzles removes this vacuum pull. It's only a guess. In any event, whatever Mazda's reasoning, I have read in other posts that the check valves in the nozzles frequently stop working.

 

I came here to see if there is any updates. I just read through a bunch of pages that are not about the topic. So,...I geuss no updates?