pakron1122

So, here's the plan for my build. To put this:


and this:


into this:


My plan is to use the stock 1.6 ecu. I have the complete JRSC kit for a 99-00. And just to keep things fun I also picked up a 99-00 intake manifold. So that's the build, thoughts?

pakron1122

I am not entirely sure what I need to change in the JRSC kit to make it work though. Which dummy throttle body do I need? Which actual throttle body? Do I need a 1.6>1.8 throttle body adapter still?

pakron1122

Oh, and just to get it out of the way, I know this is Brain's realm. But I want to keep the 1.6 ecu for cost and driveability reasons. I don't care about the extra hp I'm giving up. I know 99% of you use standalones so I'm against the grain here.

Reverant

iTrader: (10)

A VVT engine with the stock 1.6 ECU? Might as well run the supercharger with no belt to keep it simple.

pakron1122

Alright, alright can we just get past this and move on to the build?

pakron1122

By the way, I do have a vvtuner to run the vvt, if that's what you are referring to.

Savington

iTrader: (31)

Not likely. Explain to us how you're going to accurately deliver the drastically different fueling requirements of the VVT+JRSC combo.

18psi

iTrader: (76)

we can't get over the massive amounts of fail. so no.
you're using a JR m45 which is way undersized. fail
then you're dropping in a nice newer engine with a failaids stock 1.6 ecu. fail
what is there to talk about besides the massive fail?

pakron1122

Well, I'm not sure which way to go. The kit came with a walbro and from what I understand the vvt injectors should be able to handle the fuel delivery with an afpr. If not I could put in some toyota or rx7 injectors if needed. I have not done the calculations yet or know the flow rate on the walbro as the kit just came today. It also came with a JR timing boost controller to prevent detonation.

pakron1122

Those are your opinions, not facts.

pakron1122

Digging into this a little deeper...

I just did the calculations and for a target of 180hp I came up with 327cc's so it seems like there are several injectors around that range that will support this swap. At stock 43.5 psi fuel pressure it looks like 626/mx6/probe gt injectors will work. I'd prefer the newer style injector so I could get a smaller, better injector and just bump the fuel pressure up a bit.

Does mazda measure hp at the wheels or at the crank? I figure the JRSC will give another 40 hp, but if the mazda numbers are at the wheels I might need to bump the hp numbers up to 200.

After googling the Walbro, it flows 255lph which is more than enough for anything I want to do.

Does this sound about right?

pakron1122

Hmm, looks like the 1.6 ecu won't idle properly for anything over 305cc. Looks like I'll have to play with the fuel pressure, maybe rising rate?

Savington

iTrader: (31)

The problem is less about the amount of fuel and more about the shape of the curve.

The 1.6 liter motor and the 1.8 liter motor have drastically different torque curves. Let's start with a chart. This is three different pro SM motors, all built by Jim Drago. Run 11 is the 1.6, and run 12 is a VVT 1.8. (run 24 is a '99 motor) You can see the drastic difference in torque, espcially down low. This is where the 1.6 ECU is going to struggle to compensate - you're adding a ton of airflow and not backing it up with any additional fuel in that region of the map.



You're then compounding that with the addition of a supercharger, which will further increase low-end torque and compound the problem.

Long story short, you have two options. You can bandaid it together and you'll end up with a car that doesn't really idle right, doesn't really transition from <100kpa to >100kpa right, and makes less power and torque than it should. Or, you can swap to a standalone ECU, ditch the VVTuner, and end up with a car that idles and drives like it came with a VVT+JRSC combo from the factory, AND makes more power than the bandaid combo ever had a hope of making.

You're putting all this time and effort into the swap - why would you cripple yourself by skimping/being lazy on the most important part?

pakron1122

Well cost, for one. How much would an ecu cost built for my setup?

Second, is your quote "idles and drives like it came from the factory" an overstatement? I have read a lot of complaints regarding things like idle on standalones like the ms. I don't doubt for a second you can make more power with one. You can make more power on a geo metro with a standalone. My goal is to build a car that, once it's built, you can forget that it ever had anything done to it and looks, drives, and idles stock (but with more power obviously). Build it and drive it for 80k without futzing with idle, air/fuel curves, mixture ratios, etc.

And the cost. I only paid $1500 for the car and it does have 190k on the body.

pakron1122

The last thing I want is a tuner car. As I said, I want a stock looking and driving vehicle. Well, as stock as a supercharged vehicle can look. For example, the kit came with a bunch of blue and red silicone couplers and reducers. I will be changing them all out for black.

18psi

iTrader: (76)

You are coming at this so ridiculously moronic that I just don't know what to say.

I'm serious, this isn't just a flame post.

You're spending a ton of cash on a vvt engine swap, a supercharger, and whatever else needed to do this, then questioning the cost of an MS3 which you can get for 700 already built, or even cheaper if you do it yourself.

Then you question the consistency and smoothness of operation of a Fully stand alone engine management system that is years more advanced then the 30 year old band-aids that you consider running on this car.

Seriously?

I suggest you step back and try to comprehend how idiotic this all looks to the rest of us.

I'm done here, so you don't go on crying that I hurt your feelings. Good luck.


PS: the part I bolded REALLY made me laugh. With band aids and with a roots type utilizing the dummy TB setup, you will have THE WORST OF BOTH WORLDS. Not even kidding. Your idle will blow, and everything else will be horrifically inefficient or inconsistent. I've actual real world wrenching and driving experience with both "ROUTES" being discussed here.

pakron1122

Thanks for leaving my thread as you have nothing productive to add it seems.

pakron1122

Sav, can you explain what I'm looking at with these dyno charts. I understand the charts will look different. They are vastly different engines. What is unclear is what this has to do with the ecu. Let me explain.

The amount of air coming into an engine is fixed. Now that I am adding more air, we adjust the fuel to match. Why does it matter what ecu you are running as long as the a/f mixture is correct? This can be done mechanically or electronically. Since I don't want the expense of an electronic solution, what is wrong with a mechanical solution? People have been doing it this way for 100 years. I just feel like you can get it pretty darn close this way.

18psi

iTrader: (76)

ahh, so you're one of those too stubborn and stupid to be helped.

k

no problem
Oh this should be stickied





99% sure this guy is trolling.

pakron1122

Weren't you leaving?