Carb to Injection conversion

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no1newb

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Does anyone know anything about some of these carb to fuel injected conversion kits? i may be interested and dont know what i would need to be looking at/for. or if it would even be worth my time. knowing its mostly a daily driver.
 
A friend of mine had a truck with the Holley Projection unit. That one is a throttle body injection (TBI) like the stuff from the 80's/early 90's. It has a control unit that you "dial switches" for all sorts of fuel control. He had hours into tuning it, was very patient... and hated it... The thing would have run the same, maybe better with a nice carb. TPI (like edelbrocks) or a magnum engine conversion I dont know about, but have been interested in it myself. From my experience with aftermarket ECU's on fuel injected cars it takes a tuner who knows the stuff, a dyno, and lots of drive time to get it dialed in. Somebody on FABO has a 318 magnum with the injection still in place. Do a search, or he may chime in..
 
might want to contact http://www.mass-floefi.com/ or http://www.fastmanefi.com/ or http://www.diyautotune.com/
last link is to a company that someone on this site works for, I think it is madscientistmat, might want to send him a pm, he is very knowledgeable....

That would be me. We don't do complete turn-key conversion packs yet; you'd need a couple other components if you used our hardware. We have done a couple comparisons between carbed and EFI cars, and in many cases the power output was the same but the drivability, area under the curve, and such were much better. Here are some things to consider in an EFI package.

1. Completeness. Some people want to buy a package that has everything ready to just take out of the box, bolt on, and go. Other people would rather select each component and match it to their needs. Obviously, the second approach is more work; the price can come out different either way, but sometimes an off the shelf kit may have some parts sized wrong to fit a particular goal.

2. Origin of the system. Some packages are built around refurbished stock electronics off something or other - Mass-Flo, for example, uses Ford 5.0 Mustang electronics, and there's several companies that use GM hardware. (I'm not aware of any built around Mopar computers, although I believe the Pro-Jection's throttle body is related to a stock 318 TBI.) Others use aftermarket computers (the FAST or MegaSquirt systems in the above links are only distantly related to anything used by OEMs). General rule, a factory computer would be cheaper, while aftermarket computers were designed to be tuned by someone who doesn't have a million dollar budget and an engineering degree.

3. Tuning type. This can range from no tuning (not quite as bad as a carb you can't rejet if you're using a mass air flow sensor, but can still reduce your options) to the screwdriver adjustments on the Pro-Jection (an approach no other surviving system still uses) to tuning with a laptop. The last is kind of like a carburetor with a different jet for each combination of RPM and vacuum signal - only you can change the jets while the engine is running at full throttle. Many of the systems out there allow you to use a wideband oxygen sensor to give the computer the ability to tune the fuel on its own once the engine is up and running, but I would recommend having a manual back up in case this goes wrong.

4. Feature set. A carb to EFI conversion really only needs to control fuel. However, you could add ignition control, which lets you dial in advance curves which completely disregard the limits of a mechanical advance mechanism and let you get the curve nailed down even better. However, while it's possible to tune the ignition without a dyno, you'd want to plan on some dyno sessions if you want to get it better than a non-computer controlled ignition. Other features you could get include fancy ignitions with multiple coils, making the computer control your cooling fans, built in nitrous control, sequential injection (timing the injector pulses, mostly helps with a smoother idle and better emissions, and a small gain in fuel economy), and a lot of other stuff. You have to decide if it's worth it, though.
 
That would be me. We don't do complete turn-key conversion packs yet; you'd need a couple other components if you used our hardware. We have done a couple comparisons between carbed and EFI cars, and in many cases the power output was the same but the drivability, area under the curve, and such were much better. Here are some things to consider in an EFI package.

1. Completeness. Some people want to buy a package that has everything ready to just take out of the box, bolt on, and go. Other people would rather select each component and match it to their needs. Obviously, the second approach is more work; the price can come out different either way, but sometimes an off the shelf kit may have some parts sized wrong to fit a particular goal.

2. Origin of the system. Some packages are built around refurbished stock electronics off something or other - Mass-Flo, for example, uses Ford 5.0 Mustang electronics, and there's several companies that use GM hardware. (I'm not aware of any built around Mopar computers, although I believe the Pro-Jection's throttle body is related to a stock 318 TBI.) Others use aftermarket computers (the FAST or MegaSquirt systems in the above links are only distantly related to anything used by OEMs). General rule, a factory computer would be cheaper, while aftermarket computers were designed to be tuned by someone who doesn't have a million dollar budget and an engineering degree.

3. Tuning type. This can range from no tuning (not quite as bad as a carb you can't rejet if you're using a mass air flow sensor, but can still reduce your options) to the screwdriver adjustments on the Pro-Jection (an approach no other surviving system still uses) to tuning with a laptop. The last is kind of like a carburetor with a different jet for each combination of RPM and vacuum signal - only you can change the jets while the engine is running at full throttle. Many of the systems out there allow you to use a wideband oxygen sensor to give the computer the ability to tune the fuel on its own once the engine is up and running, but I would recommend having a manual back up in case this goes wrong.

4. Feature set. A carb to EFI conversion really only needs to control fuel. However, you could add ignition control, which lets you dial in advance curves which completely disregard the limits of a mechanical advance mechanism and let you get the curve nailed down even better. However, while it's possible to tune the ignition without a dyno, you'd want to plan on some dyno sessions if you want to get it better than a non-computer controlled ignition. Other features you could get include fancy ignitions with multiple coils, making the computer control your cooling fans, built in nitrous control, sequential injection (timing the injector pulses, mostly helps with a smoother idle and better emissions, and a small gain in fuel economy), and a lot of other stuff. You have to decide if it's worth it, though.

Do you have guys who can do the install?
 
Do you have guys who can do the install?

Yes, but we don't have a large installation staff and right now we've got things pretty booked through February or so. If your timeframe is after that, drop us a line when you're ready. If you're looking for somebody in the Atlanta area for an EFI install right now, you might want to contact Balanced Performance; we've got a fairly close working relationship with their people.
 
im doing the opposite a injection to carb conversion, so maybe if you want you may wanna look at my 89 stock two barrel TBI holley, i believe its a 600 cfm stock for those.
 
Bumping this up one more time.

FAST has this EZ-EFI throttle body kit http://www.fuelairspark.com/ezefi/default.asp

Now they're coming out with EZ-EFI multi-port retro-fit kits http://www.compperformancegroupstor...re_Code=FS&Product_Code=302000&Category_Code=

Of course there's BigStuff3 from John Meaney. http://bigstuff3.com/
He started with DFI from Accel in 1991. Then he had his hand in a system for F.A.S.T. Now the guy has his own company. http://bigstuff3.com/

Or back to the MegaSquirt system?

Decisions, decisions......


Wylde1.
 
Lemme' do a bit of looking. I could have sworn that there was a MOPAR MAG article written in the last year that was a great kit. 1200.00 but was almost completely drop in. The only part that was remotely difficult was welding a bung in the exhaust for the O2 sensor.
Not a cheap kit but very user friendly.
It is programmable, but it was completely capable of tuning itself also. They boasted that the O2 sensor and other factors would have the car "dialed in" with in the first several runs down the road and would constantly tune it self (O2 sensor obviously) Either way it sounded like a great kit and the install was very realistic. Ill see if I can dog it up again.
 
I sell and support all the FAST stuff. You should really check out the EZ-EFI system on my web site.
 
I have had a Holley Projection 2 on my Newport 383 since 1996, w/ O2 feedback. Hard to say mileage improved over the 2 barrel carb. It is hard to get it to idle smooth, probably because the spray just hits the throttle plates and dribbles in. It does run good at high rpm. I got a used Projection 2D on ebay for my Dart for ~$180, plus an O2 sensor. I cleaned it up and swapped parts to my Newport to insure it worked. The digital box is neater w/ direct O2 connector, but I can't adjust idle any smoother. I haven't tried swapping O2 sensors yet.

I don't think the Projection is worth the >$1K list price. Maybe if you find one cheap. I am a design engineer and don't understand their theory of using just TPS and rpm, w/ no manifold pressure sensor. I also don't like their harness. They could have used much smaller wires for most. Several times a wire pulled loose from their connector at the ECU. It appears they just crimped wires, with no solder. Nothing like that to strand you on the side of the road. Megasquirt looks much better and I would love to control both fuel and spark.
 
Personall think a tbi system and a mega squirt would be the way to go.Simple.
 
Personall think a tbi system and a mega squirt would be the way to go.Simple.
other than it being simple, why would you want to use what is basically an electronic carb? one of the benefits of the a tpi type system is the dry intake, no fuel distribution issues. getting the injectors down into the intake allows you to fire the fuel directly into the cylinder that needs it. it also allows you to only supply fuel to the cylinder that will be firing. tpi allows you to inject the fuel at the precise time it is needed, improving efficiency. it also allows you to target the cruise are of the spark/fuel tables, to get as much timing and lean the fuel out as far as you can, again improving efficiency. depending on the system you are using i am pretty sure that you can tune the ecu to turn the injectors off entirely while slowing down. i am far from an expert on EFI, so my statements above are just from my researching some of this stuff....that, by the way, is my disclaimer:cheers::cheers:
 
I'm going the Bone Yard path. I have a TBI, wiring harness, computer from a 90 GMC. I know that the E-Prom will need reprogrammed.
 
We just installed a MSD atomic on a Charger, already had MSD ignition. Hardest part was; you can't get their pump below the tank, and it won't work. You have to get a kit to install somebody else's pump in the tank. I think it was tanksinc.com that MSD tech said to call. It was a nice kit.

Run their 3/8" hose for supply, to efi, run hose on return (use the return system, we found out returnless doesn't work) to a 90 lb regulater(we had a 440, it likes 60 lbs), then you can use the original 5/16" supply as a return, that pump set up has provisions for return. Oh, to get the lines in, involves cutting out a plate, above the pump, in the trunk floor.

After all of that, it is drilling more holes in the firewall, since the MSD ignition is in the cabin, and the units like to talk to each other. Buy the 4' extension wire.

Then, it fires right up. and you can run that extension through the passenger window, and the passenger can fine tune the computer while driving.

A/F ratio at idle, cruise, wot, it reads engine temp, map,rpm, everything.And you can adjust it with the handheld. You can give it more squirt, reset transition, like changing a power valve, on the fly.

That car runs so much better now, and faster. If you have the MSD dissy, you can buy the kit, and lock the dissy; then use the handheld to set initial, cruise, and wot timing.

The only downside is; People stare at a restored 69 Charger. All they see is a wire coming out the hood into the pass window, and I'm sitting there, looks like I'm tapping on a video game controller. It works, but the system ends up to be $3000.
 
THANKS!! for your efforts. I would be interested about where did you get the "big schematic," is that something you bought, or downloaded somewhere?
 
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