Spittybug - Designs for converting stock setup to EFI

[Spittybug]

Adam, where did you get that "Rice a Roni" air intake tube? I'm having a hell of a hard time finding a rubber elbow that would do the job. Yours looks like it works!

[AdmiralSenn]

Adam, where did you get that "Rice a Roni" air intake tube? I'm having a hell of a hard time finding a rubber elbow that would do the job. Yours looks like it works!

Believe me I struggled for EVER to nail down a solution to that problem - I went through about five iterations of my intake before I got one that actually seals and doesn't fall out when you look at it funny.

There's a brand of cheap "tuner" products catering to, for lack of a better word, "ricers" - dudes with old Civics and coffee can exhaust tips. The product line is called Spectre, they're sold at Autozone and Advance Auto Parts, and probably O'Reilly's as well. (I guess this makes my car a potato ricer. ) Note that most of these places won't order Spectre stuff for you, so if they're out of stock I'd look on eBay.

The tube is regular air intake hose - identical in every way to the "cold air intake" the regular vendors sell, only it seems to be a little longer (at least the one I bought from a vendor was definitely shorter than the one I had installed before the fire). It comes with an extra adapter piece in the box that may come in handy when attaching it to a filter - see below.

Now then. the piece I used to adapt it to the rubber on the throttle bodies is a 3" to 2.5" intake pipe reducer - same brand as the hose and air filter. I did have to cut a few rings of material off the small end of the reducer to make it fit without touching the butterflies, and I also had to trim the flexible hose to keep it from flopping all over the engine bay - it's pretty long for this application, but you'll want that extra length to connect certain pieces later.

The chrome piece is ALSO a Spectre part (and optional, but still useful), but I had to special order it - it's not always in the stores. It's a vacuum tube adapter, used to add things like idle air intake and air temperature sensors after the filter. I also needed a kit of the various size nipples that fit in the adapter, which I also had to order - again, your selection may differ. From the reducer to the vacuum adapter I just have a piece of the same flexible tubing between the parts. The tubing is designed to fit inside certain Spectre products and make a seal without really needing a clamp, though I would recommend one anyway.

Spectre part numbers:
Flexible Intake Hose (black) - 8741, mine came with part 8147 for attaching to a filter
Reducer - 8751 (there is also a part 87511 that appears to be identical but made of a different material)
Vacuum fittings - 9713
Vacuum sensor adapter - 8707
Air Filter - 9132

I do have a clamp set and an adapter of some kind on the air filter as well but I am not entirely sure which parts they are, and those will be dependent on the type of filter and individual preference anyway - and it's not as if EVERY SINGLE PIECE has to be from this brand, it just makes it a little easier for a one-stop shopping trip if you don't happen to have things like 3" band clamps laying around.

The filter setup is a 3" hose to a 3" filter, with a plastic gray piece that makes the hose slip into the filter (provided with the flexible hose), and a 3" ID tube with clamps over them securing the whole thing - it's a tight fit.

I also intend to buy at least some of their brackets - 8701, 9402 and/or 9701 - to make the flexible hose stay EXACTLY where I want it, and also to put positive pressure on the reducer to make 100% sure it doesn't move. It's stuck in there so tightly that it's not going to pop out unless I really pull on it, but I don't like leaving things unsecured. I may also replace the flexible hose with a solid tube later if I can either find it in another finish, cover it, or convince myself to tolerate that much faux chrome in my engine bay (probably never going to happen!).

Of course this is all to hook the hose and filter up to a standard K-Jet manifold, but they make a TON of rubber and PVC and silicone elbows, adapters, and so on that come in super handy for jobs like this of any type - might even help with the 604 or OEM EFI manifold installations.

(Incidentally, this seems as good a time as any to mention that I have a gutted K-Jet mixture box if someone wants it for measurements or experimental fiddling. The unnecessary (for EFI) holes have been clumsily sealed off with some form of gasket making material but I did use this on my car for a good while and as far as I know it didn't leak. Really just want it and its component parts (I still have the guts) out of my garage.)

[cineman]

I first posted that picture to DMCTalk.com, but the original credit goes to Cineman. It was in either an Alpine or a custom built racer. There was a throttle body attached directly to each plenum. The engine suffered a fire, I think during a race. I don't remember if it's been rebuilt since.

here it is:




you can find lot other photos in my picasa collection
https://picasaweb.google.com/cinemanvero

[Spittybug]

here it is:
you can find lot other photos in my picasa collection
https://picasaweb.google.com/cinemanvero

For anyone that hasn't checked out Cineman's picture collection, DO SO! What a great source of "been there done that" photos to help you see how to do things or how things are supposed to look. Some of those turbo engine shots are awesome!

[AdmiralSenn]

I ran mine directly to the battery negative terminal (this was before my ground bus upgrade). I figured that this method meant WAY fewer possible problems with grounds later. So far I've been unplagued by that particular problem.

I just ran a bundle of wires behind the parcel shelf so it's out of the way. Pretty easy to do.

[cineman]

For anyone that hasn't checked out Cineman's picture collection, DO SO! What a great source of "been there done that" photos to help you see how to do things or how things are supposed to look. Some of those turbo engine shots are awesome!

Thanks I'm running my 3rd engine now in my car, a 3.0lt efi PRV twin turbo based on a renault Safrane twinturbo and Alpine GTA engine parts... in some weeks i will have a quite final setup to show...

[Spittybug]

Some good news. I've been picking brains over at the Megasquirt site and it looks like we can forgo the throttle position sensor with minimal issue. The primary fueling algorithm uses the manifold pressure (MAP) not the throttle position. Only in some cases like heavily modified cams would one contemplate using the Alpha_N algorithm. The other time that the TPS data is used is for the acceleration enhancement feature. This too has the ability to look at the rate of change in MAP or rate of change in throttle position. It has been my experience to date that the TPS is more difficult to dial in than the MAP and wouldn't be missed. Lastly, the TPS is used to detect when the throttle is wide open at start, indicating a flood clear. This can be accomplished in an alternate manner, but is a minor issue for a fully configured car in any case.

So, I'm working on the idle air block and the fuel rail hold down mechanism. The stock air deflector plate comes off with one screw, but ultimately I'd like to get a flexible air duct to connect the intake of the throttle body to the underside of the stock air cleaner and get the whole K-Jet fuel assembly (and its weight) out of the car. It's looking like mating to the throttle body is a bit of a challenge that will require crafting a bolt on flange which an intake hose can be connected to.

Having everything off the car and on the bench to play with angles and visualize things from different sides really helps. Stay tuned.

[AdmiralSenn]

Have you considered mating the adapter I use with a 90 degree bend? I don't recall the diameter of the original air cleaner (never had one on my car) but it seems like finding a rubber piece to do that would be fairly trivial.

[Spittybug]

Have you considered mating the adapter I use with a 90 degree bend? I don't recall the diameter of the original air cleaner (never had one on my car) but it seems like finding a rubber piece to do that would be fairly trivial.

With that funny rubber flange we have on the intake side of the throttle body, getting a good, reliable seal is a challenge. Making an aluminum mating plate or maybe even making a plaster cast and using it to make custom rubber boots are ideas I'm considering. This wouldn't be a problem if the face of the throttle body had a lip (like most throttle bodies) over which a boot or tube could be attached.

I took a 4" PVC union coupling and using my lathe, reduced the diameter by enough so that it fits snugly inside the bottom of the air cleaner. Also provides a place to drill a hole for the air temp sensor to sit in. I don't know if I'm on the right track with that or not.

[Spittybug]

Well today I was able to stretch a 3" flexible PVC coupling over the oval flange that sits between the throttle body and the fuel unit. I made 4 slices for the the mounting tabs to stick out and had to put it in boiling water to soften it. Not good. Even though I got it on there and it was acceptably tight fitting, when the whole assembly went back in place the downward angle of the throttle body made the rubber boot squeeze up against the bottom of the manifold. Nothing would be able to mate to it.

Unless a custom (fiberglass?) air tube can be fabricated to mimic the fuel unit's profile to connect the throttle body to the stock air filter, the solution will need to be simply removing the air deflection plate but leaving the fuel unit on board. Not ideal, but I'm really having a problem with the confined space, sharp direction change and lack of good mating surfaces.

That was, of course, after watching my daughter's school, OU, kick the crap out of arch rivals Texas in the Red River Football Shootout today. There is a perverse satisfaction wearing my OU shirt here in Houston!