Air Pump Delete for EFI upgrade

This is a close up of the emission decal I been working on off and on in photoshop for my truck to reflect the new non stock setup to make life easier.

The warm/cold air aspect of the air cleaner will be the red vacuum line from Man Vac to the A/CL Bi Met.

It is manifold vacuum to the A/CL Bi Met which is the Air Cleaner bi metallic switch.  It then go the A/CL CWM or Air Cleaner Cold Weather Modulator and then on to the A/CL DV or Aircleaner Diverter which is the vacuum motor that selects cold or hot air.

the Cold Weather Modulator along with the Bi Metallic switch are temperatures witches.  The Bi Metallic switch is the one situated in the lid of the air cleaner after the air filter.  the Cold Weather Modulator is situated near the snorkel to allow air to blow across it cooling it or warming it up to maintain a preset temperature.

It's easy enough to make it work, and not look terrible.

I guess how important it is depends on your climate where you live.

Ok, you're showing vacuum restriction before Cold Weather Modulator.

And obviously "Carb" will be TBI.

Correct, and the vacuum restriction before the CWM is only if you have A/C.  My truck doesnt have factory A/C so that restriction is not found on my truck.  I have been meaning to make some changes to the diagram cause I dont need the vacuum temperature switch for the timing cause the main purpose of that is to switch between ported to manifold vacuum when starting to over heat to idle the engine up.  With a TBI fuel injection setup you advance the timing the IAC will just bring the idle speed back to target.  So it would serve no purpose.

So I am going to have to remove the colored vacuum lines from that circuit and I will need to switch the Carb text to TBI.  But I might be able to leave it Carb considering my Stealth looks just like a 4150 double pumper and with me wanting to run AN flared hardlines I can route it just like the OE mechanical fuel pump line to complete the illusion of a carb setup.

I've got to assume "only with AC" because of the throttle kicker changing rpm and vacuum suddenly?

Yeah if your EFI can detect coolant temp, idle speed and control advance there's no need to have manifold and restricted vacuum, controlled by the TVS sent to the advance unit.

Is there a need for vacuum advance at all?
How much range does the Sniper have, Rusty?

I think this might be super useful for me, but man, I’m having the worst time trying to keep up with the acronyms in diagrams. I’m sure it’ll be second nature eventually.

One thing I’m wondering - if I’m adding a heating element to the intake manifold, do I need to heat the air before it get’s to the cleaner? I’m sure this is probably a straight up newb question, but I am what I am. LOL

On the sniper it has the ability to control timing but you have to buy their distributor for timing control.  I honestly would not recommend going that route because they have a lot of problems with introducing RFI into the sniper system causing issues.

Now as far as idle speed goes, the sniper can control idle speed up to some 2,000 rpm as a max.  With the CTS you can use the free computer software and set idle speed based off coolant temp so you could have the engine idle higher below 50*F and then have it idle higher above 240*F.  There might be a way to be more precise with smaller temperature increments I am not sure the software is a bit too advanced for me to know all of what it can do.

But without timing control the sniper can control idle speed.  Can control idle speed to idle engine up when the A/C is on and can also control idle speed up or down based off temperature.

If you have heating in the intake like a intake heat cross over you really dont have to have the heated air with EFI.  In my case I wont have it, my Edelbrock Performer dual plane intake I dont believe has the heat cross over and my AFR cylinder heads dont even have the Exhaust cross over ports so in my case there will be no exhaust heat on the bottom of the intake manifold so in my case in cold weather around 30*F which is quite possible where I will eventually be moving to it poses a concern to me if I should have the hot air setup functional or just have the hoses hooked up and blocked off with a bb.

On the emission acronyms this is what I saved as a reference for me.

Jim,

I do believe Gary has a list of all the vacuum acronyms we could gather.
I know that back on FTE we put together a list that was stickied.

While it might not have Engine Control Unit, Powertrain Control Module, Thick Film Transistor, Spark Out, Profile Ignition Pickup or Electronic Engine Control, it does have a bunch of the mystery vacuum initials like Thermal Vacuum Switch and Vacuum Control Valve.

There really can't be a crossover on a 300, where the intake is hanging entirely off the right side of the engine.

Waiting for coolant temp to get up to where it can make a difference is literally like watching water boil.

Correct, but if I remember right on the I6`s the carb sits on the intake which makes up part of the exhaust that helps to warm the bottom side of the intake up to help the fuel vaporize quickly.

This is all I have, this is my entire vacuum acronym list, the one I posted above is a quick cheat sheet as its the most common ones.

And he's just said he is using the dual EFI manifolds that have no provision for heat because they don't even meet under the plenum...

But, yes most carbed 300's can have a heated floor, if they retain the stock exhaust.

That's really comprehensive Rusty!

Would you mind sharing it with Gary, and the forum?
I can see where that's a great reference for many members.

Ah, I must have missed the part about the EFI manifolds.

In that case I would try to run the heated part of the aircleaner.  Sure with EFI you dont really need it cause it has a air temp sensor to compensate the air/fuel ratio.  But question that I have always wondered what the difference in warm up time between hot air intake and no hot air intake.  We know pulling in warm air will help to warm the engine up faster than pulling in ice cold air.  But at the same time I am curious if it will cause a driveability problem with the sniper setup by throwing the fuel table off tricking the ECU into thinking its warmer than it really is.  But knowing about the system I dont see how it could.

That’s incredibly helpful! Thanks!

Here’s the heat plate for the Edelbrock I ordered. http://autoparts.rasoenterprises.com/index.php?route=product/product&product_id=8

I don't think its really tricking the ECU at all, Rusty.
Coolant temp is what it is.
Intake charge temp is what IT is.

It will certainly lessen or prevent icing of the carb or (in your case) throttle body.

And that's never a bad thing.

That looks like a nice unit!
It will certainly help with charge atomization in cold weather, once the coolant gets up to temp.

Thats what I figured.  You have the ECT and the IAT.  It shouldnt matter if its 30* outside and the engine is at 100* and the intake temp is 100* from the heat riser.

It should all work fine regardless.  I just have to cobble the system together as best as I can since I will be omitting some circuits that I wont be using with the fuel injection since the efi can take over.

I know icing is less of a problem with a tbi but it still can happen.  Ive had GM TBI`s at work at idle and in 20 minutes on a 80* day the TBI was sweating its butt off from the temperature drop due to the pressure differential.  I could just imagine the icing forming if it was a 50* or 60* day.

It's not just the venturi Rusty.

Every bit of that fuel needs to evaporate, and that consumes heat.
The phase change between liquid and vapor takes many times the amount of heat it takes to bring a liquid to boiling (which it MUST do before becoming a vapor)

A jet atomizing a liquid tremendously increases the surface area, but in order to become a vapor, rather than an aerosol it needs to phase change.

/Geek