Least expensive way to get EFI on a dinosaur engine?

[Thumpin455]

Lets say I have an MSD EFI fuel pump, wideband O2 sitting here, the capability to solder, no fear of wiring or tuning, and I want fully tunable EFI that can handle a 500hp 455 that pulls more than 15hg running cattail vodka. I am seriously considering either building or buying EFI for my latest engine.

Where do I start?

How much injector do I need?

What kind of throttle body?

Not not a TBI setup, unless one of the new ones will let me program them for my fuel.

[Beagle]

the cheapest biggest throttle body I can think of is a 460 Ford. The elbow is kinda tall and ugly, but if it will fit under the hood, you can adapt it to a 4bbl manifold easily. Big 4 bbl tb's are getting cheaper and cheaper, but I see these for 20.00

Alky tosses a wrench at the injectors I think? They'll probably need to be pretty big or have 60# of pressure to make up for the difference in stoich. I'd probably not consider anything smaller than 42's, but what RPM out of curiosity? 5000?

DIY megasquirt is my next plan - actually I'm thinking about a microsquirt. I think Randal ran his without idle control for a while, I'll let him answer that if he sees this. It's a little short on features compared to the MegaSquirt, but all I will want is fuel control. I'm not even remotely concerned about SEFI - I spent an afternoon in the park staring at the sky and contemplating how short of a time fuel is gonna pack up behind the valves one day an came to the conclusion that unless it's the last ounce of economy or emissions, SEFI is a sales pitch. Batch firing two banks works just fine for me.

I'm cheap so all of this should be junkyard sensor driven. I think the current crop of Megasquirt has an onboard MAP?

Immerse yourself in this for a bit: http://www.megamanual.com/index.html - a lot of questions that will pop into your head are already answered. Welcome to the sickness.

[GH]

Also, while you are at the junk yard, get an EDIS wheel 36 tooth, and the sensor off of a Ford and some LS coils of off a GM. Then you can run the ignition through the MS. I spent $40 for 2 throttle bodies, 8 coils, the EDIS wheel, sensor and one of those flexible exhaust pieces.

[Thumpin455]

The yards up here think stuff is made of platinum or unobtainium. They want $650 for a 130k mile 5.3L. Might have to see if some others can scrounge the stuff and send it to me for a finders fee. I think this is going to be the winter project, making either the 65 or 70 road ready with EFI on a mild but relatively high compression 455. The fun part will be fuel rails, unless I decide to put them just under the TB NASCAR style. Since I am running ethanol that would be a good way to utilize the latent heat of vaporization qualities. Could weld some bungs on a Torker II that has been on the shelf for a long time.

I really like the idea of the LS coils for each plug. There is quite a bit to be picked up there, and mostly this project is about efficiency, secondary is power. Minimizing misfires will go a long way to making this thing run how I want it. Good call GH!

[Beagle]

Explorer is a good LS type coil pack source, 2 coil packs, four per coil pack... missing tooth balancer wheel, all the junk is external on the 302 in that so you can liberate and fit as necessary. LS wheel is internal? Grab the Cam Position Sensor too, you can modify the parts to fit.


I'd serously consider buying a 89 (pretty sure EFI big block started in 88 or 89) up 460 truck if you can find one, should be able to find a fubar or wreck for a few hundred and get most of the sensor and harness stuff for a decent entry level Speed Density setup. Take what you need, junk the rest, you will wind up with parts and money I bet. You have the space, maybe not the time. If you have the time, I think you can win doing it this way. GM stuff may be doable to, I'm just not familiar with it. Most of the Megasquirt stuff plays very nice with Ford junk and maybe a couple of GM sensors tossed in which might be smarter to get new for a few bucks. The Ford harness is extremely well documented, and the similarity to an LS makes munging them together pretty freaking simple.

In all honesty, I'd dip my toes in with something besides a 13.5:1 e85 / alky motor just because the tune is so much more forgiving and small injectors so much more accessible. You're gonna do whatever you want of course, expected, so I hope you don't mind me saying that. It might be a cheap easy way to get acquainted before putting it on a more money long block.

The shallow end of the pool is fuel only, which is so well documented it's crazy. If you're really serious, we might be able to get a EFI jy setup from down here to up there. The lack of rust and non-snapping bolts might f*k you up though..

[anotheridiot]

I think the cheapest way is to machine bosses into the manifold and leave the carburetor on it. I dont think there is anything wrong with using a carburetor without using it for gas. The carb is just your throttle body for air, the fuel gets sprayed in the manifold and you are injected. Just use a standard old air cleaner assembly and clamp your mass air on the spout, just make sure you really keep the air filter clean or clamp a KN type deal on the MAF and leave the regular one out of the standard air cleaner. It should work.

[dieselgeek]

There's some good advice in here. GH has probably the "baddest" setup for the lowest possible price. LS coilpacks are no joke, they'll spark PLENTY hot - plus they get rid of all that noise in the distributor, and eliminate underhood open sparks, thus less fire hazard.

For the ECU, a retuned GM computer might be cheaper but a Megasquirt will give you more control and is more up your alley, you being a DIY guy. Whatever you need, plenty of us here can help, if you decide to assemble one yourself or just buy one preassembled...

You'd want either a Megasquirt-2 or 3 to run your coilpacks. MS2 will run them in wasted spark, ms3x will run them sequentially if you want to rig up a cheapo cam sensor (CDMBill's cam sensor was $30 plus a tiny bit of fab work, again right up your alley).

For a crank trigger, again GH's 36-1 Ford wheel is the way to go. Not with the EDIS ignition box, IMO, just the wheel and the pickup sensor from an Escort or whatever distributorless Ford engine you can find in the 'yard. Or online (beware, you want a GENUINE Ford part IMO, not the stamped chinese pot metal wheels that don't trigger as reliably from what I have seen). Then drive the coils directly with the MS.

Got questions? ask them here. I'm sure you of all people will have a blast with this project. Plenty of folks here can help you work through the configuration too, which is usually the part where you will have most questions.

[TheSilverBuick]

Yep weld in your own injector bungs on an intake. Use an old Q-jet for a throttlebody, get one of those with the TPS built in if you have one laying around. Cam sensor can be made from grinding some teeth off an HEI pickup coil. I pulled an Escort's balancer/pulley/timing wheel from the junkyard then separated the trigger wheel off that. I don't remember what the pontiac's pulleys look like, but if you can get it mounted on the pontiac balancer or crank pulley you'd be doing good for a crank sensor. For absolutely cheapest though, you can just use an HEI distributor and have a megasquirt(2) plug right into the pickup coil and not have a module in there. Then run a conventional HEI distributor/coil having the megasquirt control timing either through an MSD box or directly hooked to the coil.

[Thumpin455]

You guys are awesome. The more I think about it, the more I want the coil packs. Its all about mileage with this thing, that is why it has the small 224/230 cam and lots of compression. It just happens to make lots of power like that. Here is the cam it has http://www.summitracing.com/parts/CCA-51-423-9 so it should have plenty of vacuum and it has a very nice idle, wont that make tuning it easier?

Where do I find injectors? From what I can tell I need at least a 40# injector, but a bit larger would help with duty cycle right? Is there anything I can find them on or is it one of those things I need to order?

Can someone explain the difference between high impedance and low impedance injectors? I know what it means as far as Ohms, but what does each type of injector require to run it?

[dieselgeek]

40 lb/hr injectors is getting into the "pricey aftermarket" injectors. Most of us will recommend HIGH IMPEDANCE injectors. High Impedance means "low current requirements" - all ECUs can drive low current injectors, but only a few of them have the capability of driving High Current injectors. Megasquirt 1, 2, 3 can drive High Current injectors on their "bank" circuits, but the MS3 (the one that will do v8 sequential injection and spark), can only drive LOW current injectors sequentially. Again, any MS can drive high current injectors bank-to-bank or batch firing, but if you want full sequential injection (and spark) you need to go with the MS3, and low current injectors. Hopefully that wasn't confusing? lol

Finding injectors of that size might be a challenge, 40 lb/hr is officially above any OEM sized injectors I know of, so you end up having to purchase expensive aftermarket units. However, you COULD do something like we did on the Spectre Maverick a few years ago - double down on smaller, cheaper injectors you get from the junkyard (16 20lb injectors will work) if you can't afford a set of fresh 40 lb units. Or buy a set of 42s from someone online who is upgrading, and spend a few bucks to have them cleaned and flowed...

[Thumpin455]

So by doubling up you mean 16 injectors instead of 8? I was thinking about welding the bungs in the bottom of the intake so it is all hidden, Pontiacs will fit it all under there easy due to the valley pan and intake design. I have a whole mess of 5.0 Ford injectors sitting here, they are from F150s. I think they are something like 16-20lb arent they?

Also it will be running around 60psi due to how I am using the fuel, I know that changes the flow rates somewhat. I want to add heat to the fuel while its in the rails so it vaporizes completely and instantly when it hits the intake port. That means a return less/deadhead system like the LS1 has, otherwise I am just heating the fuel in the tank. That means the pump and injectors are sticking points, the pump needs to be high pressure and not burn out, the injectors need to handle 60psi and 200F fuel temps. Since engines get about that hot anyway, I dont think its an issue. The pump I have should work, it is rated to run at 60psi continuous in a deadhead.

I am thinking MS3 right now, it will do what I want it to do. I looked at the prices of it and it isnt too bad, I have spent more on carbs. Might as well start off with the most capable one so I can add the coil packs and crank trigger as time allows. Sequential would be preferred if the injectors are down the ports, but batch would work too with what I am doing and using a single plane intake or mounting the injectors NASCAR style like a plate N2O system.

[dieselgeek]

The dead head pump is going to be an issue, you'll need a complete in-tank pump and regulator for LS engines if you really plan to run it that way. Plenty of guys do so it can be done easily enough, you just need the style of regulator that has its return right at the tank...

a TRUE dead head system will be harder to set up, like what's on many Ford modular engines. That requires the ability to control a pump with PWM and, in my opinion, is too much of a science fair project to try and do with an MS for your first EFI system.

[Thumpin455]

I was thinking more like the LS1 fuel system, easy to set up because I can copy it from my Formula. While looking around on the 98s, it looks stupid easy to set up the fuel heating manifold on both the LS1 and 3800 I have. On the 80s and early 90s stuff it was much harder to get to the connections, and Ford made it even harder to get it done with the connectors they used on 5.0s. I remember fighting with those things and that is a big part of why I am not using a Ford for this project.

The reg by the tank is probably a great idea actually, except for adjusting the pressure manually would be a pain crawling under it. Building an in tank pump isnt that hard as long as the tank has a large enough opening, I could also run a fuel cell if needed. Pretty sure the GTO has a larger opening in 70 because of the vents and return lines they had, I know 79 Firebirds have the big opening so they are easy. It also helps with the stealth idea of putting it all under the intake.

Thinking about two injectors per port, the easiest way is to set them one upstream from the other in the ports. That means four fuel rails, or one on top, one under the intake. DG do you have a suggestion for the fuel rails? Ford style tubing or GM style machined aluminum? Whichever way I go it will have to be custom built because of the port layout and two injectors per port.

The more I think about it the more I think two injectors is best, it gives plenty of headroom if it needs more flow, and larger injectors can be used later. It adds complexity, but doesnt require high end injectors, stock stuff would work.

[dieselgeek]

For true rails I like the extruded aluminum you can buy almost anywhere, drill it yourself. But a few companies, BDS is one, thread injector bodies letting you run an individual hose to the injector versus using a rail. That allows grouping secondary injectors in a circle around an air charge pipe, upstream of the throttle body, leaving room for conventional injectors aimed at the intake valves.

[Thumpin455]

Then you can plumb it like a nitrous system, hard lines from a distribution block. That could look very trick or very ugly depending on skill. Anything else come to mind?