Thread: Carburetor vs EFI

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I’ll admit my ignorance regarding electronic fuel injection systems… basically I don’t know anything about them I can, however, work around most carburetor problems and can actually read a spark plug to properly jet a carburetor if I need to tweak the performance of an engine. What I’m wondering is if any of you guys are using the new EFI systems on any of your rods? I know that some of the new crate engines come with them, but I’m not sure if they are a pain to set up and maintain. I’m starting to “dream” about a future project, and I’m picturing one of those new Hilborn EFI tube injector setups sitting on top of the engine

Got any opinions or ideas about these injection systems?

Dan J

You gotta see a picture of what I'm drooling over...

Dude, give me a little warning, okay? That setup is positively gorgeous. I shoulda wore my drool cups since I'm doing the Pavlovian response thing to the point that I'm afraid I'll short out my keyb

Dan, I tried to find some pictures of a friend of mine that has the Hilborne set up with mapps sensor. If I can't find it (the picture) I'll take one of it next weekend at a cruise we're going to. It was an expensive deal to install, and he had some problems early on. It turns out that the fuel line went from big to small and back to big and he couldn't get the right injector pressure. It took some time to find out that was really the problem. The shop that installed it should have known better. We have a friend that has the program and knowledge to tune it anyway he wants, he's at about 800 hp. It now runs great and he has no problems driving it from sea level to altitudes. He drives this car everywhere. There are a number of people I know that have this setup and other EFIs and they swear by them. All had some minor problems early on, but so do carbs sometimes. I'll get some pictures for you within the next couple of weeks.

Yeh W2, I’m mopping up my keyboard too! But, I didn’t catch myself until the computer blew a circuit breaker Sorry if I caught you off guard… you’re not on heart medicine or anything are you???

FMJ, I’d like to see pictures of your friend’s setup when you get a chance. I’m also curious to know if any other aspect of the engine setup is different with EFI than it is with a carburetor setup (i.e. compression ratio, cam selection, ignition, etc.). I’m not really looking for mega horsepower, just the “look” and a dependable machine.

I know all of the new factory cars run EFI and are pretty much trouble free. But, I’m curious to know if the computer aspects of the aftermarket setups are anything like my desktop computer… you know, crashing occasionally

Dan J

Dan,
Man that is a great looking system. The first image that popped in my mind was a '64 Dodge 330 sedan with those stacks poking through the hood, bolted to a nice little (?) Hemi!! Great way to have a driveable car with visual impact.

Now for reality. I haven't done a system on a rod, but appreciate it's advantages on "civilian" cars in the fleet. Like fmj I've got a buddy, who is wrapping up a '50 Ford convertible with a 5.0 out of a late model Explorer.

I don't know how many times I heard him say "man, I coulda done a 4 barrel for a whole lot less money and trouble". The money part comes from the parts being more expensive, even though he got the entire system with the takeout engine, and work, some of which you farm out if you're not an electronic FI guru.

As for parts, there of course is the modified wiring harness, throttle body changes, extra fuel line for return, a high pressure fuel pump, since the donor most likely won't fit the rod's tank, and then a miriad of "little" parts and pieces it takes to tweak the system to fit in the transplanted environment. He also had innumerable phone calls to Street & Performance, and Ford Motor Sports, the answers sometimes conflicting between the two. He ended up buying some recommended parts that ultimately didn't help and had to be replaced with something else. His final saving grace was in finding a local shop that had genuine expertise with electronic FI. Once he got it all together they were a huge help in getting it fine tuned so it would run beyond barely. And then there was something I didn't realize, on a transplant, apparently the computer has to "relearn" the operating perameters of the new set up, which takes some 30-35 starting/driving cycles.

Like so many areas, the learning curve can be a pain. For all that he went through a lot of grief in the process, he's very pleased with it now that it is on the road. As for cost, he hasn't really admitted a number, but based on my memory of discussions along the way, I'd say he's got an extra $2k in the installation. And he started with the complete system on the engine!!

It'll be interesting to see if ghostwheels is still hanging around and will have any comment.

Wow Bob, I think my drooling problem is starting to subside Sounds like this could be pretty expensive "window dressing" for a street rod! And then, I'm wondering if the advertised "plug and play" aspect of the EFI manufacturer has been handled by the advertising department instead of the engineering folks? It'll be interesting to see if any other brave souls have been down this path before, and are willing to tell their story.

Dan J

Dan,

I ran a Hilborn EFI set-up on a small block in a Cobra. They are very streetable when tuned. I sold the car a couple of years ago but got an e-mail from the new owner recently telling me how much he loved the car and syste. At that point it's been on the car for about 2 1/2 years.

Unless you can find a used system, figure on $4500 to $5500 to do one of these. I didn't use a factory computer; FAST, Holley, or Accel Gen VII would work great. Hardest part is getting the vacuum lines run as since it's an individual runner set-up and has no common plenum, you need to tap into each port for each individual vacuum source you need. I had three lines per port, two hidden under the manifold and one on top. I needed one for the map sensor (which shouldn't be shared with anything else), one for idle air control, and one for pcv/power brakes.

Here's a pic of my setup:



Jody

Jody,

Thanks for the input. I took a minute to check the link to your cars, and it appears that you are running a turbocharger on a couple of your rides… all are good looking vehicles.

You mentioned that the EFI worked well once it was “tuned”. Does this involve computer or mechanical tuning? And wow, I had no idea that each vacuum supply would require that each individual port be tapped… isn’t it possible to tap each port and create a single vacuum plenum?

Appreciate the insight!

Dan J

Computer tuning. Not much mechanical other than getting the throttle bodies synched. The thing is the MAP and IAC need to be on their own separate vacuum systems, especially the MAP; you don't want to share them with something else that will be using and not using vacuum (like power brakes). The brakes and pcv can share, but the other two need their own separate lines. They'll work sharing but every EFI tuner I know says not to do it.

Jody

Okay Mr. Dan,

Here's another alternative for an EFI conversion, just in case you haven't chucked the idea altogether yet. Of course you'd have to come over to the "dark side" (way traditional).

This is from an outfit called Classic Gass, www.classicgass.com . They make a throttle body to look like a Stromberg 97. Just another in the multitude of choices we have.

Bob, you are just cruel I haven’t thought about this fuel injection thing for a couple of days… I thought that maybe I could get myself un-hooked from the “vision”

Thanks for the extra option to be considered. Somehow, this fuel injection thing still makes me nervous.

Dan J

Either systen looks somewhat like a dream I had. Boy would I like to borrow a few bucks. No sense banging my head. No cash rebuilt the old AFB.

Is this on a Chevy? You should try GM's RamJet setup. It makes tons of low end torque and gets decent milage.

Hey Dan.....did you get a FI set up? What was the final outcome???

If you want the multi-carb set up.....go with one of the best! It will run close to the pricey Hilborn set up.

Check it out!

http://www.cobrasbyxks.com/pages6/weber1.html