Mazdaspeeder

Say what? Lol

bigllama

Geez. I just read through this thread--what a roller coaster! It reminds me of the early day experiences I had looking for H2FJDMTRS (that's Hard to Find, Japanese Domestic Market Trick Racing Stuff).

Vlad, part of the issue (imho) is that you have too much easily available kit and too much mechanical talent. So you have a hard time making a decision and sticking with it.

Even now, you are still sitting on two different turbos...

--Miq

EO2K

iTrader: (37)

The stock NB pump is already pushing it pretty hard on the top end at its 60psi base pressure. I don't remember who did it, but its been tested to be marginal on the top end even in stock form. Pressure ≠ volume. Checkit:

That should say 99-05. Pumps and fuel systems are the same. More good reading here: Fuel Pump - Miata Turbo FAQ When it comes right down to it, $100 for a new fuel pump is cheap insurance against failure or out of spec 14 year old pump.

DNMakinson

iTrader: (3)

I made some pictures. I'm sorry that I don't know how to say this in a short post, but, no-one has to read all of this.

Assumptions
The same power requires the same volume of fuel.
In all cases the power, the boost and the injectors are the same.
Any unused fuel that the pump pumps is returned to the tank.
There is no pressure drop in the lines.
The boost is at 15 psi in the manifold.
The tank is at atmospheric pressure.
The relief valves are perfect.
The Manifold referenced valve is set at 45 psi.
The Stock 99+ atmospheric referenced valve is set at 60 psi.
The Stock pump, by the graph, flows 35GPH at 60psi.
The 190HP, by the graph, flows 45GPH at 60 psi.

At these conditions:
Both pumps operate at 60 psi.
In the Atm Ref system, the pump pressure is set directly by the 60 psi of the FPR, resulting in 60 psi. The difference between the pumps is how much fuel is bypassed and returned to the tank.

In the Manifold Ref system the pump pressure is set by the 15 psi of the Mani Plus the 45 psi of the FPR, resulting in 60 psi, which the pumps see. The difference between the pumps is how much fuel is bypassed and returned to the tank.

The assumptions are not 100%, but that results in small differences, not major ones.

At higher flow rates, the return system and higher capacity pump is best as the pressure drop in the supply line becomes more important. In addition, the Stock pump runs out of volume.

This is what Jeff said. Lower power, stock is OK, and I'm saying that is true for Returnless or Referenced.

Jeffbucc

Thanks DNK, for eloquently articulating my post. People need to be careful ordering pumps without a lot of thought put into it though. The 255 was overwhelming my stock FPR, causing me to be rich regardless of my VEAL map. Once an AFPR was purchased, and set at 70psi, the fuel system was much happier.

18psi

iTrader: (76)

Thanks Miq, that has always been my problem. I have commitment issues lol

Gordon and David,
Check out this discussion:
https://www.miataturbo.net/race-prep...7/#post1102531

There was another thread where we all discussed it even more, but I can't find it for the life of me. If the stock NB system can run e85, and Emilio says he's done it numerous times, then I don't think it's as tapped out as it appears.

Jeff,
Agreed - it seems to be hit/miss, since a 255HP on my '00 with e85 and ID1000's ran perfectly at idle and FPR was fine.

Jeffbucc

A lot of the hit/miss, or erroneous application effectiveness is most likely due to the health of the FPR people have in their car as well. My NA FPR was from a 90 Miata, and 25 years of life probably didn't hold up well to the higher pressure the 255 is trying to push through it.

18psi

iTrader: (76)

Ok, so in the interest of clean, completely reversible modifications (pretty much the theme of this car) I made myself a little AIT harness. Plugs into the stock wiring, no splicing, no ANYTHING. Just pug in and go, and unplug if need to.


Then started actually tuning it. Got about an hour into making adjustments to the Rev provided base map, and realized that I'm pretty much better off scrapping it altogether and starting on my own, since his base map is designed for (I'm guessing) a bone stock car, and doesn't use a LOT of the features I like to use, like Idle VE map and the EAE settings and stuff like that.

Car now drives A LOT better than before, actually has more or less "ok" afr's and stuff. Still needs a TON of tuning, since as you already know I'm super OCD about these things and won't be able to sleep at night until it idles/drives better than stock.

One thing I noticed, is on stupid ca91 pump gas I'm having to pull a LOT of timing out after 4300 rpm, because it pings like crazy. What a difference vs e85.

I'm going to slowly start tuning it on the way to/from work, so it will take forever, but at least I'm finally making progress again

DNMakinson

iTrader: (3)

I'd say my single most frustrating part of tuning is how EAE affects starting. If not just so, then I get seeming random (I know it is not random) large swings in EAE, that cause stumbling due to lean, rich, or both. These are only 200mS duration. Do you see this as well?

18psi

iTrader: (76)

startup? as in cold/hot cranking?

haven't tuned that yet. actually there are a lot of things I haven't tuned yet, I've only about 1 hour into this thing so far. right now just focused on the VE and Spark tables, setting them up, and having the car able to start and drive repeatedly without major issues, because I need the car driving every day no matter what. I think it's good on that front now. Started up and drove to work just fine this morning.
Still need to fine tune cold start, hot restart, closed loop idle PID, EGO PID, air temp density correction, and all the throttle tip in, AE, EAE, etc. ..and then start on VVT control PID, and............the list just keeps growing LOL

*edit: btw those AEM UEGO calibration numbers didn't work. TS and Gauge line up real close for the most part, but it's still off by .01-.02 every now and then. Really frustrates me.

I'm gonna double check the 3 wires and connections, make sure they are top notch, and keep messing with the calibration. I want it perfect. Not almost perfect.

*2ndedit:
found this
https://www.miataturbo.net/megasquir...rstudio-63658/
Will try those numbers too, and keep adjusting from there. Its close enough that its not a big problem, but still bothers me like crazy.

DNMakinson

iTrader: (3)

Can affect cold or hot. I'm getting it close now, where EAE is not affecting after start much. However , there were times that with EAE off, cranking was perfect, and with EAE on, it was junk. Crank, fight for life, run.

18psi

iTrader: (76)

hmm, that is interesting. I must say that my ASE and WUE is pretty darn good right now, with barely any tweaking. My AE is time based, tps only right now, (that's another thing I gotta change and fine tune) so I'm guessing I'll be experiencing what you're talking about very soon.

Thanks for the heads up.

I'm starting to to be tempted to throw in the ID725's so I don't have to re-do any of this later

DNMakinson

iTrader: (3)

Vlad, if you don't mind, can you educate me on setting is IAC valve PWM settings during crank? Do you set them to same values as idle at same temperature, or higher, or lower.

18psi

iTrader: (76)

The way I understand it is you want it open same as at idle or just slightly more. That's how I had it set, I'll have to double check and confirm. I know I took a bunch of time setting that up on my last MS3x due to running e85 and it being a royal pain on cold start, haven't done that on this one yet.

EO2K

iTrader: (37)

Glorious progress Comrade!

I am also quite jealous of your IAT "adapter" pigtail. I did mine using a weatherpack, and I've always hated it. I may have to see if I've got a spare stock IAT somewhere.

18psi

iTrader: (76)

Ok, so today the stupid VVT wiring gremlin reared its ugly head and I learned a valuable lesson: I need to figure this crap out soon, cause it drives me nuts that it comes and goes randomly.

And with the MS it's a lot harder to keep track off too, because MS doesn't throw a code or do anything at all when vvt stops working, just looses a bit of lowend response and afr's get a bit fatter.

Let me back up and start from the beginning:

I was tuning the car on the way to work, and on the way back. Then again for about an hour or so this evening. Everything is going peachy - spark map now takes the crappy CA91 water into account and car doesn't ping and runs happy. AFR's are slowly getting dialed in where they are really solid. Idle is not bad at all. Everything is progressing slowly but surely.

After I finally put the laptop away pretty happy with the progress so far, I start remembering one thing I forgot to monitor while tuning: VVT duty/angles/etc.

So I bust out the laptop for another 30 min tuning sesh, and what do you know: vvt angle stays at like -1 to 3.5* or something stupid. doesn't change at all and doesn't do anything really, no matter what.

CRAP

I start messing with Tunerstudio/Megasquirt, trying different settings, etc. Nothing works.

I then pop hood, unplug the clip/wire going to the solenoid, drive car, same thing plugged vs unplugged.

Then I plug it back in. BOOM. Now I haz VVT. And it works perfect, responds to my adjustments, etc.

So I'm happy I caught that, but really mad cause now my VE table needs to be re-worked, because a bunch of areas are now leaner due to the VVT/Cam advancing.

I did a dyno pull anyway though

Same exact road as before, same exact everything, except the car now is BONE STOCK and running crap CA91oct

It's running a bit on the lean side, but as I already said that's due to the VVT mumbo jumbo. I'll be fixing that.



For reference, here is a plot from earlier when I had my other MS3x + ID1000 + test pipe running on e85.


So I guess that's the difference between e85 and pump 91 all else being nearly equal. The timing maps on the two tunes are DRASTICALLY different fwiw

NiklasFalk

iTrader: (1)

I have not played with continual SDcard logging, but it sounds convenient in cases like this.
Always having a log file of the two last hours would help with figuring out the rare issues.
But it looks like you could forget to select parameters you are interested in...

EO2K

iTrader: (37)

Sounds like someone needs a new VVT connector/pins.

18psi

iTrader: (76)

The thing is, this one looks perfect. If it had a single defect I'd have replaced it long ago. Guess I'll bust out the magnifying glass and really inspect it.

EO2K

iTrader: (37)

You are not really selling me on the VeeVeeTees at this point.