NZConvertible

The stock system doesn't open slowly, it "snaps" open at a certain rpm. The VDI valve must be either open or closed; it won't work properly with the valve half way in between.

rx-7fc

does any body know how to hook up one i think i know how to hook the rpm switch but i need help with it to work with the Yellow EGR solenoid so it can work for the vdi

NZConvertible

It’s basically the same as the electronic aux ports write-up at www.fc3s.org, except the pressure line goes to the VDI actuator instead of the aux ports actuators.
Whatever rpm Mazda activates the VDI at should be used. Dyno tests have proven there are usually losses, not gains, associated with changing this activation point.

rx-7fc

at what rpm does mazda have the vdi open at

rx-7fc

bump

NZConvertible

Search, search, search!

Best activation RPM for 6th ports and VDI?

nima_taba

I bought an rpm switch from Harlan Engineering....it seems to be a more versiatile unit than the MSD unit (no pills to buy), however in the instructions it says that you can't run very much current through the switch or it will fry. How much current does a selenoid draw?

If I can't hook it up directly to the selenoid...what the hell am I supposed to do?

*edit: can you run more amps through a MSD switch...as in enough to run a selenoid right off the switch?

Thanks
Nima

scathcart

one magic box, so many electrical purposes:

Relay!

silverrotor

iTrader: (1)

I plan on running an RPM Switch to open up my auxilliary ports. I have a Crane Cams Ignition Box wired to my Leading Coil Pack. Can I hook the Switch to It without any consequences? Or hook to the Trailing Pack? Why If so?

Also I checked out NZConvertible's link with no direct answer provided. I was thinking of having my ports open up at 4000 rpm. I prefer that they don't open up at 3800 rpm b'c I sometimes get the dreaded hesitation. I don't want the ports opening up at the same time the hesitation occurs.

Do the level of mods play a role as to what Is preferable when the ports open?

nima_taba

Just wondering if the relay I need is a "single pole, single throw relay". My switch has one voltage line coming out of it (single pole) and I will only need one wire going to the selenoid (single throw).

Is this right??

Thanks
Nima

blu_gxl

from what i have read the vdi opens at 5500 rpm however you might want it to open at 5000 because you have less rpm until redline than an s5 does

scathcart

I don't think you even need a CDI box to install it (isn't it just a negative signal off the coil, like a tach?)
Regardless, its fine to hook it up with your CDI box installed. No effect whatsoever. It's just a tach input.

Yes, mods affect when port opening would be ideal, but for your purposes, stock opening is fine. 4000 rpm would be OK.

scathcart

Sure... I dunno what its called, I just know what it looks like, and where to buy it. Your description sounds right. What a relay does is takes a small amount of current and uses it to connect a large current circuit together. IE: The relay itself draws a small amount of current from the switch, and then completes the circuit to whatever high current circuit you're using (like a e-fan).
However, depending on what kind of air solenoid you use, you probably won't need a relay. I wasn't really thinking last night, sorry. If you re-use a stock emissions solenoid, you shouldn't need a relay, since they draw very little current.
Just wire it to the switch.

Sorry I led you down the wrong path... but a relay wouldn't hurt, nonetheless.

nima_taba

Yeah, I was gonna do the same thing, then I read teh instuction manual which said that I should definitely not wire it directly. I have a Mini Mac selenoid...that shouldn't really draw that much current. I would hate to blow my switch though...so I guess I'll use a relay.

Thanks scathart,

Nima

scathcart

Got a link to the mini mac? I've never heard of it. Just curious at all, don't spend any time looking for a link or anything.

I didn't realise you were so close to me. A fellow canuck...

nima_taba

I didn't notice either...wierd!


Here's the link,

http://www.mpsmall.com/mps/products/mps/minimac.htm


I think I am gonna get a relay...I've done alot of circuits in school...now I gotta figure it out in real life!

Here goes nothing,
Nima

silverrotor

iTrader: (1)

scathcart/nima_taba/// You could stand to save to a few bucks by using an old ERG Solenoid. Equally effective as opposed to a $50 us. Solenoid!