Thanks Rick.

so the next question is, how do i use an output on the MS to control that solenoid then?

 

With the MSPNP i'm not sure what it would take to control the VICS. I know you can use the single shift light function AKA Output 1 but that is already being used for boost control. So the other option is Output 3 which would take a small circuit similar to the fan mod. Just a resistor, diode, transistor and a new wire in the harness.

 

then i guess i'll have to get this other MS working in stand alone mode....

 

Lets see if I can do the same with my Xede setup on my 2000 FMII setup. Time will tell...

 

And you will need some sort of volume of "vacuum" to keep the valve shut when you are at WOT under your trigger rpm of 5600. The OEM system has a little vacuum canister for this, but maybe just a regular hose with a check valve or two will be enough.

 

more complicated, more clutter. i think the electric actuator is a better option. and if the MSPNP can't do it i'll just throw the MSI parallel in after Chad modifies the board.

 

McMaster-Carr. would #70155K3 or #70155K4 on page 967 work? both are 1/2" stroke, pull. I am guessing i would need the continuous duty version 70155K4.

can MS throw out a 12v signal?

 

hey mkulak, i can't pm you back.

"mkulak has exceeded their stored private messages quota and can not accept further messages until they clear some space."

 

Doesn't a turbo change the dynamic of how the butterflies work? I'd think since you're pushing more air in with boost, it would be better to control the VICS via a pressure switch at a certain PSI rather than at an RPM since you could probably benefit from the butterflies being open before 5200 if you're hitting full boost by say 3600 or so.

Frank

 

PMs are now cleared...

 

I'd do a push style, sealed, like # 69905K74. It'd be "closed" when disenergized which is most of the time when you're driving. I'd push open when energized when you are above 5600.

Use a relay if your mspnp can't handle the current.

Not sure if you'll need a return spring or not.

 

so judging from this thread, using the shift light output on MS will NOT work to activate the vics solenoid????

 

then what will i use for my shift light?

 

Impressive. Get that thing out to the strip.

 

you change warmup to output4, and setup output 4 as your switch.

 

as if

 

Wow, this was below my radar. I've been messing with all the same stuff. On the run of the mill MS-II there's really no issue, I've got enough outputs for VICS and still have a spare (no water injection though).

Last time I had my motor apart (well, the one before, really) I put in 97 pistons for the lower compression. Actually, I got them for the 97 rods which are supposed to be undetectably stronger. Then I got a killer deal on some used Carillo H-beams. No bent rods since, and I'm sure it wasn't my tuning.


I've read a LOT of shredded 5 speeds, but very very few 6 speeds. I'm going to put one in soon in the hopes it's beefier. Already have the gears for the rear end.

Good post, but the first and last parts caught my attention: There's only one solenoid (solenoid being some sort of electric thing). The actuator is purely driven by vacuum.

http://abefm.smugmug.com/gallery/4157859

From the couple graphs I've seen, the losses at the top end are significant, the gains at the bottom are only a few percent. I'd build a log manifold, or keep VICS as is - high flow, or all around compramise. If I were to disable just the control, leave it in "high RPM" mode - you won't miss 15 hp at 3500 rpm, but you will miss 45 at 6,500.

Of the two graphs I saw (FM's on a stock car and some other guy's on a 11psi SC) it looks like the stock would have been best 5500-5600, and the FI one should be more around 5k.

Check my link. There's ~300 cc's of air in a cavity in the manifold. As much as I hated the routing, it was dumb not to use it. There's a good quality OEM check valve to store enough vacuum to fire VICS multiple times. It's in a weird place, but I was impressed with it.

It's not hard at all to get MS to do that, I do it for my fans, etc, link available on request. I do worry about it being a LOT of current, or needing a lot of cooling - I used some solenoids as shutter drivers at work here for some weird thing I was working on - and I was shocked at the amount of heat they generated. It's easy to melt one, and they weren't very strong. The VICS closes pretty hard, I mangled my finger right good just playing with it.

As Tim mentioned above, and I discovered through redoing my system a few times.... there's a factory resivior. Presumably for low vacuum at heavy throttle, but it should work just as well for being on boost.

The question of pressure verses RPM is non-trivial, the point of all of these is resonance - like a tuned exaust pipe on a 2 stroke, you want pressure pulses to "pile up" at the intake port when they open... At low RPM, this needs to be a long path, and high RPM it's a short path (less time till the valve opens again). In practice, sometimes a resonance chamber is used instead of a "long path". Anyway, at higher boost (or when using water injection) the speed of sound in the medium changes (I imagine actual flow of the medium would more or less cancel out since you first go upstream, reflect and go downstream), the dense air should have a higher speed, meaning yes, I think you'd want to trigger VICS earlier.

For me, I just have to figure out which way to do it. I haven't stopped and looked at it yet, but there's some reading here to do carefully I noticed.

Let me know if the solenoid thing works out. In the end I decided on the already-in-place vacuum system, but if someone showed it working I might change.

 

I guess this thread has been below your radar too https://www.miataturbo.net/forum/showthread.php?t=15389

getting the VICs functioning has been scrapped in the interest of <s>adding lightness</s> doing something different

 

I thought you had two manifolds. Make the VICS work on the unmolested manifold.

 

then you could dyno both and ppl would know whats actually better.