rotarygod

I hope you're not trying to maching Renesis rotors. It won't work.

guitarjunkie28

nope. i'm gonna be using heavy rotors

globi

Actually this professor had a good idea and I believe his technical issues could have been solved.
However, car manufacturers solved the pumping loss issue mainly with increased exhaust gas recirculation possibly in conjunction with stratified fuel injection. (Exhaust gas recirculation can also be increased with more valve overlap, this is probably one of the reasons why some modern engines can forgo traditional exhaust gas recirculation). Also, more gears on a gearbox or CVTs allow the engine to run at a lower rpm on a highway and simply reduce pumping losses this way. Furthermore, cylinder deactivation is even another way to reduce pumping losses.
Last and not least hybrid cars can by simply deactivating the engine at low power settings not only reduce pumping losses but cut off engine friction as well.

globi

Actually Turbos do steal power from the crank. By increasing the pressure in the exhaust system, the pressure on the piston is increased when it pushes the exhaust gas out. This increased pressure on the piston 'brakes' the crank and therefore steals power from the crank as well.
But your statement is correct that a Turbo at highway cruising is probably better fuel efficiency wise than most superchargers, since at that point it shouldn't really increase backpressure since it doesn't have to produce any pressure.

But one should not forget that any supercharger can also REDUCE pumping losses. One can take a smaller engine and run it at 'full' throttle (but no boost) at highway cruising. A bigger naturally aspirated engine with equal total power however would produce pumping losses because of a lower throttle setting and its larger 'vacuum' pump.

I wouldn't say this is the key of water injection but yes since isothermal compression is more efficient than adiabatic compression an engine can be more efficient this way.
My question would be if one can squirt water on Richards blender or whether one has to inject water after the compressor and forgo some of the possible advantages of pre compressor water injection.

davefzr

The interceptor has multiple functions for both a rapid increase in manifold vacuum pressure as well as being able to "stage" the injectors for a WOT situation. You need to change the time, amt, trig and stop cells on the Pump1 screen at the Pump2 level which will provide additional pulses of fuel depending on the amount that is specified in the amt field. This will allow you to keep a more consistent afr once the throttle is pressed aggresively.

Also, the interceptor has the capability of controlling the "staging" of the secondary injectors so that additional fuel can be supplied while in a WOT situation.

These values can be found on the options screen under REVstg, MAPstg and %Stage. Once a certain rpm has been reached this will alert the Interceptor to arm the injectors for additional fuel to be supplied to the engine. Only when the injectors are armed and the amount in MAPStg represented as a value of hg will it supply fuel from the cell identified by %Stage.

I actually had to heavily modify these values on my application (N/A) and it worked out great. The spike of 17.5 afr is down to 15 when I accelerate aggresively and my afr's at wot are just under 13 with the secondary injectors pumping in the appropriate amount of fuel. Just need to take a bit more fuel out on the RPMwot map or decrease the appropriate hg values on the LOAD screen... Almost there!

maikelnait

Hi Richard,

I've posted here before, so I guess I'm not a stranger to this thread. I'm here "representing" (If such thing could be said) the Spaniard's Rx8 club. We do not have a full-grown aftermarket for rotaries as you have, and we seem to have a pathological aversion to turbos (Even Greddys!!) for the Renesis.

You've stirred things up a bit concernign boosting up Renesis performance, and have probably "boosted" up our expectations concerning maximizing horsepower.

I'm aware you've turned down the Int-X and are looking up some other EMS.

What I'm asking is: Are you looking up to marketing your blower overseas or you're just observing th US market?

If your answer is: I wanna sell it everywhere!, could you specify a timeframe for overseas demand?

Thing is, we are really looking forward to a blower that can increase performance, without being a turbo. We seem to be afraid of heat as much as our weather anchors are .

Maybe you never noticed, but guys as JIRD20 and Juanjux have been 'round askin' the same thing...we are so committed

Thanks a lot and excuse the meanigless lecture!

Miguel

alnielsen

iTrader: (4)

I would think, this would be correct in theory. I may be wrong, but I don't think this is correct in the real world. On a road car, you create back pressure on the exhaust to quiet the exhaust. In this case, the turbo acts as a muffler. Acting alone or with other mufflers to achieve the desired sound level that is being emitted from the car. The power it steals from the engine is put to a use. On a supercharger, you don't get this side benefit.

rotarygod

You don't have to. Muffling doesn't have to rob power or create backpressure. It's all design dependent.

rotarygod

Here's my take on using the Interceptor on this project. Keep the damn thing and learn how to tune it. Don't try for a couple of days and give up. I assure you it will do everything you need it to. If this ecu is too difficult to learn, what makes anyone think that any other alternative ecu will be easier? A reflash would be optimal but someone still has to tune it. Don't sell it. Learn to use it. I'm still learning it myself (and have standalone ecu experience) and expect I'll be finding new features on it for a long time to come.

guitarjunkie28

i'll get the tuning figured out next week if richard's still down for it. i know a few things i haven't said yet.

Richard Paul

iTrader: (5)

I'm going to let Guitar Junkie take the car next week and do what he wants with it. That doesn't mean I'm happy or that I will keep it. It's only here until I get what I want. And what I want is something half the price at most and something that keeps more of the stock features, has more modern programing. That is available I assure you. There are at least two that I have my eye on now and will get both of them soon. I'll give you an honest evaluation when I'm done.

I only play stupid Fred, Ive built complete EFI units and you have to call that stand alone. I mean built the entire thing not just added an electronic componant.
I've built throttle bodys, fuel rails, intake manifolds and everything else but the nozzles and pumps.

It's only a joke when I play like I can't work with a controller. It's only a joke when I threaten to go back to carbs and distributors.
I'm just a funny guy, I can't help it.

Your forgetting one thing, even if I get it running well It's not like my customers can do it. I have to have something reliable and repeatable.
How come Scott couldn't make it work? That's what I'm talking about.
I could send him out with every kit and when thier car still can't be driven I'll refer them to you RG. Who pays for my lost sales? This paragraph was not a joke.

I'm not alone, I'll not tell tales or name names, but some other manufactures have the same opinion. I wouldn't even tell you in PM, so don't ask.

And it hasn't been a couple of days it's been a couple of weeks screwing around. That's money not made making product.

guitarjunkie28

bb gt66 feeding into the blower?
what, what?

Richard Paul

iTrader: (5)

rotarygod

First of all I wasn't trying to be mean and I've always been fully aware that you were going to pursue a different direction for the final kit anyways. I too can be sarcastic. However the Interceptor can absolutely do everything that you need it to in the mean time so giving up on it in favor of something else for the time being seems like taking a step sideways rather than a step forward. If you know there will be a better alternative in the near future, why buy the Interceptor in the first place? Why not just wait the extra couple of weeks? It's been 2 years in the making. What's another couple of weeks? I am fully aware that you are capable of doing many things. I never said or implied that you were dumb. You are extremely smart and have a lot of good experience and knowledge. I do admit that the Interceptor software isn't terribly user friendly compared to many other alternatives but that just means it's something different to learn. I'm not personally a fan of it's software but I like what it can do which means I'll have to learn to deal with it.

Now to answer the above quote. If I recall correctly you didn't have the kit working properly due to issues such as improper pully alignment and belt slippage etc and by the time it was resolved, Scott was out of time and about to leave. I can find no fault at all with Scott or his abilities and guarantee that he could absolutely make it work assuming of course that the blower setup itself works. If it works, it can be tuned.

Japan8

I'll speak out of turn here and say this...

I don't think that's what Richard meant Fred. He meant why the hell does a "standalone" (piggybacking the stock ecu) require to be tuned for each individual car even if they are running identical setups? Even for N/A applications... Scott's "base maps" do work... just not perfectly and could use or even need to be fine tuned. Why? Mazda doesn't make a ecu flash for each car. One works on all RX-8's. Unless I've misunderstood something the Interceptor-X is supposed to be in total control of the engine and thus is should work like the stock ecu... one "tune" should work on all identical setups. But it doesn't. Why? Now add in the cost (which would push the price of the costs up too high), the Interceptor-X offering more features than Richard needs for his "final product"...

It's even more clear to me now. Richard wants to build a product like Saleen or Kenne Bell. Something that is plug and play, reasonably priced and works as good as OEM.


At least this is what I gather from his posts.

deppenma

RP does not want himself/or is equipment to be blamed for any sort of engine failure.

You can always get more power but at what cost…....engine reliability.


RP keep up the good work.
When the project is done and based on RP’s past blowers the Blowers will out last the engine.

rotarygod

Japan, that makes sense.

dannobre

iTrader: (3)

We have to remember that the Closed loop feedback routines in the stock ECU allow quite a variation in sensors and therefore different engines............. to be adjusted to the set A/F values that Mazda wants. If the Interceptor had closed loop feedback that adjusted the maps from Scotts base map I'm sure they would work between cars as well as the Mazda flash.

Also remember that the hardware and the software in the stock ECU is much more powerfull than the Microtech harware........

Richard Paul

iTrader: (5)

I'm going to answer this and that will be all I'm going to say. I don't want a pissing contest between RG and myself. That was not my intention.
BUT I'll rebut your opinion of what was wrong with the car. Just about nothing. There was a problem with the belt but was fixed. It sometimes snaped around off one groove but it still was functioing I watched it myself on the dyno.
I wanted to change to the smaller pulley but Scott didn't have time. I waited around until 9:00 or 9:30 befor we got my car on the dyno.

He only made 5 pulls and made no real gains anywhere. (BTW I paid $200 for that minimal time on the dyno, which is way more then I have ever paid anywhere.)
I never ment to bitch about this but apparently some people are misinformed.
When done my car was undrivable with two dips in the power curve which when I changed to pulley became full shut off points.

No one has been able to fix that so far. The car is undrivable this way. There have been people in and out of the car since from all sorts of backgrounds and no one has come close to solving the problem. I'm not even going into the loss of power at other driving setting. Those I'm sure can be worked out.

I don't know if it does or doesn't but it should have a closed loop where you can just tell it to work out a given A/F and that would solve all the questions. The other units have that feature. In fact if it doesn't then it can't work properly without a high speed intake manifold temp sensor. It just cannot. I mentioned this going in and was told it didn't need the temp sensor. So either someone doesn't know what he is talking about or doesn't know his unit.

Now just to back myself up I found a supercharger kit sold in Austraila that tried the Microtec and stated that it was "unsuitable for this car"
I never wanted to bad mouth the unit or Scott but I've been pushed into it by people making unfair comments to me or others. The evedence is on my side, it's still in the car.

One more thing when I had the real big pulley on the car and 3.5 psi I put 101 fuel in it just so I could drive it. I put it on the dyno here and it made just under 200 SAE. After the pulley was changed to a 5psi one and scott tuned the Inter x it made 219 STD corrected. Guess what that is no gain for 1.5psi increase. And don't give me any **** about the higher octane. I'm the wrong guy, higher octane has less power in it.

That's right all of you who dynoed at GT got standard correction not SAE.

You should read all of this knowing it is only my opinion. I have opinions on everything.

guitarjunkie28

i alredy told you i'll make it work. because i'm young and agile.

patrick_andraste

My girlfriend would argue that I am even more opinionated.

I like this thread, I am learning a lot!

I have done standalone EFI on a few piston motors. This rotary thing is new to me, but by looking at it, it sure resembles a piston port two stroke without the primary compression. Still, I will wait till the people that know what they are doing before I go blowing up my own motor.

Too bad there is not enough room under there to put on some decent megaphone pipes.

I think a blower on this motor will be much better than a turbocharger. Norton when they were tuning rotaries went to megaphones without the reversion closing cone to get the most power, which to me means turbo bad, open pipes with supercharger good. You would have seen more rotaries in racing motorcycles if the FIM had not called them two strokes and gave them a 2.0 displacement factor instead of the 1.5 that Norton wanted.

Toyota experimented with two strokes in the 80's. They wanted an open crankcase with plain bearings and no oil in the intake so they ended up supercharging their motor because of the absence of primary compression. One more reason Supercharger good, turbocharger not so good.

Hymee

iTrader: (1)

No "Primary" compression??? Please explain? The renesis has a full 10:1 compression cycle between induction and ignition.

But yes - I like the S/C path for the RX-8



Cheers,
Hymee.

r0tor

iTrader: (1)

That has always been my one real problem with the interceptor - no closed loop feedback. There are 2 major drawbacks because of this, one of which we already see..

a) one map will not work for all cars like a factory map since the ecu can not compensate for how various tolerences stack up in each car

b) the other drawback is overtime, the interceptor will absolutely need to be retuned to stay at peak performance as various parts of the car get wear and need to be accounted for... think air filters, spark plugs, 2 sensors, seals, and everything else that effects combustion. You can see a stock cars long term fuel trim generally trend up over time between service.

there is a reason why fuel strategies in the oem ecu have long term and short term fuel trims as well as linking for non-closed loop areas in the map to closed loop areas of the map.....

patrick_andraste

By Primary Compression, I am referring to when the piston comes down in the crankcase, compressing the air fuel charge in the crankcase and then blowing it through the transfer ports to above the piston. Then the Piston rises sealing off the transfer ports and compressing the air fuel mixture and creating a vacuum in the crankcase which then sucks air and fuel in through the intake.

Exhaust port(s) open first and close after the transfers, so by using expansion chambers the opening cone provides scavenging and the closing cone provides reversion of the charge to push unburned air fuel mixture back into the cylinder before the exhaust fully closes.

Antique two strokes use piston ports where the piston skirt is essentially the intake valve opening and closing the intake port, just like the rotr on a rotary motor.

as an interim motorcycle manufacturers opened the intake timing greatly and used the piston as the opening timing of the intake and a reedvalve to seal it off or provide the closing timing of the intake.

Then intake ports were opened to the point of 360 degree timing and after that the reeds were moved straight into the cases.

Piston port motors will make more peak horsepower but reed valve motors make more power everywhere else.

my point being is that since there is no overlap in the rotary motor, you would want only a megaphone exhaust to provide maximum scavenging and provide more vacuum in the combustion chamber so when the intake opens there will be more of a pressure differential to hopefully pull more air in through the intake and with air stacking with increased velocity of the incoming charge perhaps packing more air and fuel in.

with a supercharger though, the need for a megaphone exhaust would be fairly negated.

Richard Paul

iTrader: (5)

:my point being is that since there is no overlap in the rotary motor, you would want only a megaphone exhaust to provide maximum scavenging and provide more vacuum in the combustion chamber so when the intake opens there will be more of a pressure differential to hopefully pull more air in through the intake and with air stacking with increased velocity of the incoming charge perhaps packing more air and fuel in.



I think RotaryGod has a thought like that growing in his head right now.