Idle valve Idea for JRSC m45 kits
 

The long hose running from the IAC -> check valve -> intake elbow
also you think about the vaccum from the supercharger in the intake elbow were the iac valve line is tapped in
kind of a lot the Idle valve has to overcome
When we deccel we get a droop in idle, some of us almost to stall out

When i look at my data logs, the Duty cycle of the idle valve is "twitching" from open to close in idle.
Really not 100% if this is the soul reason why, but it could be possibly or at least contributing to it.
Either way, The long hose just plain gets on my nerves, its wedged in between my headlight housing and scrunched over my brake lines

My idea is to just delete the line, put a check valve directly on the Idle valve port and then a small filter
so it cant leak boost, or breath in dirty/contaminated air

https://www.miataturbo.net/attachmen...ine=1412612474

Here is a stupid little picture I drew, you see the current set-up and then what I think i might try

Did this work / help with idle droop?

I never had a chance to try it.
But...i posted the same thread on miata.net and found that this would only slightly help the iac valve recover, compared to just doing a dual throttle set-up.
The reason the iac fails at hard deccel with an m45 is because the valve opens back up while there is still boost, which throws it off.
When you do a dual throttle mod or a mp62 remote mount iac, you get the iac to never see boost. Thats how you fix it. And the plan that i presented still does help, and free up a little bit of room/complexity

Attachment 126032

zack. I just picked up an m45 sc kit for a 96 miata. It seems complete except it is missing the IAC Check valve and the short hose end. Any idea how I locate these missing items?

an MS3 with a few minutes tuning the idle control would work better.

Idle check valve idea
 

I have no idea what an ms3 is....

Call TDR.

TDR sells them.

The dual throttle body solves the idle problems of the stock JRSC, and creates a bunch of new fun challenges.

The solution posted earlier here screws the air flow meter up.

Only if you're running the stock ECU & a piggyback/bandaids.

True. Or more correctly, if you aren't running speed density or alpha-n.

I'm in the process of prepping my 1.8 for mounting the M45 supercharger. New timing belt & waterpump. I was thinking about mounting the voodoo box for fuel management & MSD prior to doing the SC. What's the consensus?

I would agree with the approach. You may even go one step further and do the fuel management first, timing second, SC third. That way you can hopefully isolate issues that pop up. I am not familiar with the voodoo, but if you are running tan tops at stock rail pressure on a 1.8, you will run over 80% duty cycle pretty quickly. You may want to run an aftermarket fuel pressure regulator and pressure gauge to boost your pressure. Definitely check the fuel pressure even with the stock regulator. You will certainly want wideband.

Does your SC kit have any boost upgrades?

you mispelled that.

voodoo box + MSD is spelled: DIYPNP

Ha Brain, baby steps man. He will come around as the aspirations mature. Full standalone is intimidating at first.

no it's not.

I'm running stock pulleys on the SC. I will start the work on voodoo first. Do you really think I'll need a fuel pressure setup. I will buy a boost gauge, but only after everything is up and running

Do you have a wideband? What altitude are you at?

And it is a fuel pressure gauge, not a boost gauge :)

An m45 on a 1.8 is not going to boost much more than about 4 psi. If you are at sea level you will need to supply ~30% more fuel than stock to run at 12.5 A/F. I have seen stock tan tops get wiggy after extended 90% + duty cycles, this was on a 1.6 @ ~ 7.5 psi, afr 12.1, 3 bar fuel pressure ( manifold referenced)

If you were in Denver (like me) it is only a <20% increase in duty cycle.

I would really recommend corky bell's book "supercharged" if you don't already have it. It will help you to understand the basics of fueling among other things. I have seen them used on Amazon for really cheap. It was the first book I bought when I got started, and I couldn't put it down.

I'm located in pennsylvania, close to sea level. So you're suggesting I replace the tan top?get a aftermarket fuel pressure regulator and fuel pressure/air mix gage?

Definitely get a wideband. Who knows if the voodoo is working properly or wired in correctly or has a vaccum leak?? You could (and I would reccomend) skipping the timing box at 1st. Get the car running safely with your timing at 5 or 6 degrees btdc,(I forget what JR reccomends) then start pushing the envelope with timing. The plus side is that you will get to feel what difference is made and appreciate each step more. (and stay safe / not have to replace your head gasket)

I am recommending that you read the Corky Bell Book :)

Corky Bell "Supercharged"

Sea level is good, you will have more power and probably can get good gas (93 octane). Don't even think of running lower octane.

Sea level is bad, it could push your fuel system to its capacity limits.

The issue here is that you will be increasing the fuel demands on the existing fuel system without any instrumentation to verify that the fuel system:

a - has the capacity to support the increased requirement
b - is actually providing the increased fuel

I don't think you will ~ need ~ to get different injectors initially, and I would suggest that you don't, assuming that you are able to check the function of the fuel system. The best method to do this would be with a wideband air to fuel meter. This device will tell you what you A/F is real time.

The JRSC installation manual instructs you to check the fuel pressure for the dynamic rate fuel pressure regulator. This method of fuel management is "dumb" because it simply increases the fuel pressure at a 10:1 (relative to manifold pressure) ratio when in boost. While this is a crude method, it does achieve one benefit; it increases the capacity of your fuel system by increasing the fuel pressure.

The voodoo box on the other hand uses a superior method of increasing the injector on-time. This allows the injector to exhibit more predictable and linear characteristics because the pressure differential across the injector remains constant. Injector behavior changes with differential pressure. The Voodoo box does not however increase the capacity of the fuel system. So for instance, if the stock ECU is commanding 80% of the available fuel capacity (which is a measurement of time -> read book) and you need an additional 30% of fuel, then you will run into two major problems. First, the injectors only have 20% left to give, which will run you lean and could cause bad things to happen, and second, you will run the injectors at a duty-cycle that will exceed their ability to dissipate the heat that builds up in the coils, potentially causing malfunction.

So, what do you do?

Check the fuel pressure. Old fuel pumps and old pressure regulators can wear out. Charging/Battery system degradation can reduce the fuel pump's flow rate for a given pressure. Sans a manifold pressure reference (see boost gauge) you will have to be organized about how you do this. We can discuss later if needed.

Set base timing to 6 - 8 degrees.

Install an aftermarket fuel pressure regulator. Adjusting the fuel pressure can get you a higher fuel capacity with your otherwise stock fuel system. Play around with the calculators here:

Fuel Injector Calculator from WitchHunter Performance

to see what that means.

When you can, instrument your car. I am a huge fan of instrumentation. The base instrumentation would be the A/F (wideband), manifold pressure (Boost), and Fuel pressure. The fuel pressure doesn't even need to be piped into the cabin, but it is a lot better that way.

I know this seems like a lot, but I promise if you read that book, it will not seem so daunting.

Thats your problem. I had the same problem on my turbo when i tried to use the xede piggyback.

I'm looking at a LC1 wideband and gage for the 1.8. Will this solve the fuel pressure regulator problem? I'm going to hold off putting on the MSD and set the timing at 8 degree retard

LC1 is a great wideband.(Although they now have an lc2 for roughly the same price) It will let you know if your voodoo box or whatever you wind up using to control fuel is working, and if its working hard enough. The lower the numbers, the richer the engine is running. You will want to see 14.7 at idle / cruise. You will want to see 11:1 to 12:1 at wide open throttle / in boost. you will want to see 22:1 when coasting (no throttle).

Once your afrs read like that (or close to it) then get a bipes or msd box if you want to play with it. BTW I would reccomend starting with a base timing of 6 degrees rather than 8. Baby steps. (unless you like repairing things that break)

Umm no, a wideband will only tell u how badly your engine is tuned.. holding off on the msd and timing is a bad idea since you'll be running full timing in boost. A wide band is a gauge that tells YOU the nut behind the wheel whats going on in the engine, it wont fix it for you.

Sir, open up that wastegate so you're not spooling before you blow your shit up. You have some reading to do.

You can set the base timing with the CAS and go safe. As I mentioned, 6-8 is advisable. Six is safer than 8, but with this setup you will not be running much boost. It is really easy to set, you can run 6 at first and then go to 8 once you get it fueled properly if you want.

The WB will help you dial the Voodoo in as well as telling you if you have a fueling problem. You will want this. I run AEM, innovate also makes good stuff I hear, get the one with a gauge.

The fuel pressure/capacity text from my previous post still holds.

Waiting to hear if that solved your idle droop...I went mspnp2 to solve my problems!

Don't have idle droop cause I haven't put in the SC yet. I have the dual trottle body which supposed to cure that problem anyway. I've just changing the oil on the sc and when the weather clears, getting the timing belt and waterpump changed. It's too damn cold in the garage to do any work right now

All the problems of the Moss/TDR/"who ever slapped their logo on someone else's parts and sold it to you" dose even know how this shit really works. MP blowers are not ment to be on the hot side of a inline motor. They picked up a cheap blower, made a bracket, and got some really shitty piggy backs.

The only way to fix the idle and driveability problem is to idle the car over 1500rmp or go standalone. Duel bodies are a pain in the ass is a band aid. The piggy backs you are running are costing you ~1/4 at the minimum of available power out put. Found 60whp (190 to 250) going from tdr tuned powdercards to a MS2 the first time to the dyno. If you want perfect driveability go stand alone and put the TB back on the intake manifold.

http://oi59.tinypic.com/ojj95s.jpg

Dammit..... I like that..................

Ted. Got everything together. Air fuel and boost gage installed. Runs and pulls fine but drinks 93 gas and keeps stalling at stop lights