Best EFI System for BB Chevy

[Matt H.]

I'm building a big block chevrolet engine that will be over 500 horsepower and I am looking for a good port injection system. I would like one that uses a 4 bbl throttle body. From what I know, Edelbrock and Holley have been very good but I have never used either. Any suggestions or information would be great. Thanks.

[ProTouring442]

As far as I know, the Edelbrock can't be tuned via a laptop. It uses a chip that is programed by Edelbrock, then it can be fine tuned through the included tuning console.

The Holley is laptop tunable. This is what I went with, I also wanted a 4-barrel style. I think Accel also makes one.

Shiny Side Up!
Bill
'72 442 "Inamorata"

[Matt H.]

how is the holley system working for you?

and if anyone has any experience with any of the other ones could you share them with me

[ProTouring442]

Oh..... ahem.... I haven't started it yet. :rolleyes: Hopefully I will have it out by spring.

You know, I've said that before.

Argh.


Shiny Side Up!
Bill
'72 442 "Inamorata"

[KAA]

Do you have oval or square port heads?

I had an Accel DFI Gen 7 system on my engine and currently have a Holley Commander 950 Pro. The Accel system is more sophisticated and can be run seqential injection whereas the Holley can only run in bank to bank mode. Not a bid deal really. However, one nice feature that DFI has is individual injector trim where you can modify the pulse width of each injector seperately. I could really use that because my Holley oval port manifold is showing some pretty uneven air distribution. They can both control spark with the correct distributor.

Which brings me back to the subject of manifolds. If you have oval port heads, I'd recommend the DFI manifold. The Holley oval port EFI manifold has the peanut port sized oval ports which required a LOT of grinding to match my oval port heads. This is most likely the biggest cause of the poor air distribution I'm seeing. Judging by my spark plug coloring, I'd say I have a range of 13.0 to 10.0 AFR at WOT between some of my cylinders. That's a lot. That's where the individual injector trim would be nice. You could compensate for some of that.

[BThibodeaux]

Bill is correct, the current Edelbrock Pro-Flo system requires a pre-programmed chip. It uses technology that is outdated IMO. Addtionally, it is only available in an oval port version. Edelbrock is coming out with a completely tunable system late this year. It will utilize variable flow rate injectors, which are pretty cool. You can see it on Edelbrock's website. The Accel system is nice, but it is pretty tall. The notes say that it requires a minimum of 12" of hood clearance due to the use of a high rise intake.

I ended up going with the Holley Commander 950 universal kit, the Edelbrock EFI Victor Jr. manifold for rectangular port heads, and Accel 48LB. injectors. I need it to support around 650 HP. The total cost was about $2,150 through Summit.

[4mm]

Edelbrock is coming out with a completely tunable system late this year.

Can you post a link? I couldn't find it on their website. Is it their Pro-Tuner series?

[BThibodeaux]

Can you post a link? I couldn't find it on their website. Is it their Pro-Tuner series?


Yes it is the Pro-Tuner system. Here is the link.

Shortcut to: http://www.edelbrock.com/automotive_new/mc/efi/pro_tuner_main.shtml

[Silver69Camaro]

We just dyno'd a 427 small block and we installed a FAST EFI system. One of the best I've ever seen, and made an easy 538HP. It also has individual cylinder time/fuel adjustments, which we didn't bother with...

[Matt H.]

i have oval port heads, and i definately want a 4bbl throttle body and tuned port injection, so it looks like its between FAST, Accel, Holley, and Edelbrock so could anyone just tell me the pros and cons or just the differences of each one?

[KAA]

I can only speak for the Holley and Accel systems as those are the only ones I have personal experience with. From what I've read, FAST is one of your higher end systems. I know absolutely nothing about Edelbrock.

Holley Commander 950 Pro:

Low end no frills. Lower cost alternative to DFI. Programmed via laptop PC. Easy to understand and tune. Bank to bank injection. Wideband 02 compatible and can easily accept any manufacturers wideband 02 controller input. Forced induction/NOS compatible. Can control ignition timing using inexpensive, readily available late model small cap GM HEI distributor. Excellent documentation. Good tech support. There is an EFI forum on Chevytalk.org that is virtually all Holley related and a Holley employee who runs the C950 on his car responds quickly to tech questions. Oval port EFI intake manifold is soso. Needs a lot of porting to match oval port heads. Only two sizes of throttle body available. 1000cfm and 2000cfm. 2000cfm throttle body has dominator size flange.

Accel DFI Gen 7:

Things may have changed since I used this system. High quality hardware. Wiring harness is much nicer than Holley's. ECU seems very well built and solid. Nicer software user interface. Programmed via laptop PC. Wideband 02 compatible but was not as easy to adapt a non-Accel wideband 02 controller to it. They tried to make it hard or impossible so you were forced to buy their WB02 controller. I heard they were going to change that with a new software realease but I sold my system before it came out. Several different throttle body sizes and configurations available. 1000 cfm, 1200 cfm, 1350 cfm, 1550 cfm, etc. Oval port intake manifold is much nicer than Holley's. Can control timing but requires a special DFI only distributor. Can run sequential injection with that distributor also. Distributor requires an external ingnition box. Has an injector trim feature that lets you fine tune the pulse width of each injector individually. Very nice feature. Has two different "keys" or "tongles" that let you access different features of the software. The standard key gets you partial access to the software and the "Pro" key unlocks more features. I found this to be VERY annoying. If you lose the key, like I did, you're screwed. The system comes with the standard key. The Pro key is an extra cost option. Stupid. Tech support was next to non-existent. This was also very frustrating.

[KAA]

i have oval port heads, and i definately want a 4bbl throttle body and tuned port injection, Not trying to nit pick you but want to clarify the terminology. The 4bbl throttle body EFI systems are not tuned port. They're referred to as Multi-Point, or Multi-Port EFI systems. Your tuned port injection (TPI) systems like the ones found on 84-9? Camaros, Firebirds, and Vettes, have an intake with a large plenum with equal length "tuned" runners and a throttle body located at the front of the plenum. The intake manifolds were specifically designed for EFI. Your 4bbl MPFI intakes are just single plane high rise carb intakes with fuel injector bosses cast into them. Accel, Arizona Speed & Marine, GM, and Street & Performance are the only companies I know of that make a Big Block Chevy TPI style EFI intake.

http://www.azspeed.com/45autpisywgm.html

[BThibodeaux]

i have oval port heads, and i definately want a 4bbl throttle body and tuned port injection, so it looks like its between FAST, Accel, Holley, and Edelbrock so could anyone just tell me the pros and cons or just the differences of each one?

FAST - From what I know, FAST is probably one of the best EFI companies out there. Their systems are very tunable, and allow for lots of options. However, to my knowledge they do not sell any complete or even near complete systems for the BBC. This means that you will have to piece the components together (throttle body, harness, sensors, fuel pressure regulator, fuel pump, injectors, manifold, fuel rails, idle air control, etc.). This allows you to tailor your system to your exact needs, but it will also be the very most expensive way to go.

Accel/Holley - I think the pros and cons of these two systems have been adequately addressed in the earlier posts to this thread. If you go with the complete Holley system, it is going to cost six to eight hundred dollars more than the Accel. The Accel manifold is probably going to have better flow characteristics, but not many stock hoods can clear it. If you are only looking to make 500HP, optimum flow is not all that critical anyway.

Edelbrock Pro Flo - I had this system on one of my cars. It worked very well for that application (slightly modified ZZ4). It is probably one of the most complete systems on the market. The price is comparable to the Accel system. The downside is the lack of tunability, and the requirement of a custom chip for each application.

If you go with a complete system package, you will want to confirm that the included injectors will be adequate for the kind of power you want to make.

[Matt H.]

ok, so from what ive been hearing FAST is supposed to be very good and so is holley and Accel but i think Edelbrock is out of the picture, but to clear up one issue, price doesnt matter i want to know the best one regardless of price oh ya, would the Accel system clear a 2 inch cowel hood?

[customcam]

Matt you dont work in Fullerton do you?

[mstennes]

I have the Holley MPI C950 Pro Wide Band with the throttle body where the carb would be. If I were going to keep it I would go with FAST's controller. IMO the Holley system is a big PITA. Holley's tech support totaly sucks and actually made things worse. On the throttle body where the throttle attachés is a weak spot it needs to be knurled so I have had slippage which has caused allot of tuning woes. It is low end to say the least and to me it only gives bragging rights that you have a EFI, as a well tuned carb works better. We spent allot of hours tuning only to have anew problem pop up. With some tweaking on the actually program I think it could be better in the cell area. I have talked to allot owners with Holley's system who say the same thing who went with FAST's as it was a better thought out system. To bad you don't have a small block as I will be selling this system here in about a month when I tear the car down. I read somewhere that the computer programmer who wrote the system actually wrote Accells first then Holley than FAST's. Accel has tweaked theirs where Holleys is the same, basically as the first ( I started out with the pre pro system). If you really dig deep you find the reason Holley's is the lessor known and used. Doug F is the mod over at Chevy Talk and a R&D engineer at Holley. Hes a good guy and has helped allot I just got to a point where I wanted a control unit that was faster, and able to process more. The other thing I don't like about Holley's system is, it is set up to use floppy's and a serial port. Most all new laptops have neither. It is also a DOS based system which shows its kinda dated. That being said it will work you just need patience and lots of it. Don't even think about using it without the wide band as that really gives it more tuneablity and it doesn't like big cams either that was a big tuning headache. Hope I helped.

I forgot the Holley system does not like low voltage at all, so if you have a big stereo or other high voltage items go with at least 130 amp alternator.

[ProdigyCustoms]

If you want to step up to a FAST, we can set you up with as complete a package as you need. You will spend $3500 to $4000. But it will be badd ass! We also give a custom start up program.

[Matt H.]

hey prodigycustoms, could you possibly give me a list of parts i would need so i could get a price?

[ProdigyCustoms]

I need you to tell me what you need. And I will need specs and goals to properly size the package.

Email me at [email protected] or call four zero seven 832 1752

[Matt H.]

ok I've been doing a bit of research and from what I've heard the FAST XFI system is a bit too elaborate for what I need so I've narrowed it down to Holley and Edelbrock. Is there anyone out there who has had experience with the Edelbrock system?

[Stuart Adams]

I used an Edelbrock system on my ZZ502 motor and it ran great. 4-5 more mpg and 30-40 more hp. No complaints and customer service was fine to.

[camcojb]

I used an Edelbrock system on my ZZ502 motor and it ran great. 4-5 more mpg and 30-40 more hp. No complaints and customer service was fine to.

Very true, works fine a milder combos. It is somewhat limited in tuning compared to FAST, BS3, Holley, etc., and cannot be run on a forced induction setups. But when tuned correctly it works very well.

Jody

[Stuart Adams]

FAST, BS3 are awesome systems. Especially for guys like Jody that can actually use the system, for an idiot like me -no way!

[camcojb]

FAST, BS3 are awesome systems. Especially for guys like Jody that can actually use the system, for an idiot like me -no way!

I'm positive you could learn to tune it Stuart, you're a very smart guy (not that "smarts" have anything to do with it). I enjoy doing my own tuning and as long as I can continue and am not grenading my stuff I'll keep doing it. It is simpler in most cases to find a trusted tuner though.

Jody

[Stuart Adams]

Jody is too modest guys. He can tune with these systems, so call him day or night for tech help. LOL. Jody is the man, lets see some shots of that car of yours someday dude.

[Matt H.]

ok here are my engine specs

477 cid, 11:1 compression, brodix racerite oval port cylinder heads, crane hydraulic roller camshaft (i forgot the exact specs) the engine should be around 520 horsepower, with a stick shift transmission. what would you suggest for that?

[Matt H.]

between holley and edelbrock

[Matt H.]

anyone?

[tracy]

I know you have already rejected this but I would still suggest letting Frank at Prodigy put together a system based on the FAST controller. This is going to be the most flexible setup you can do since you can hand pick, with Frank's help, every component in the system.

Worst case you can find someone local that can tune it for you. Otherwise, I think Frank has access to someone that can help you tune it if that is even necessary.

This is the route I am going with my BBC.

-Tracy

[Matt H.]

im not worried about tuning i know a guy who can tune anything, the reason i decided against FAST was because from what I was told the system is really more than i need and its more sophisticated than i need. i talked to someone at prodigy and they said it was mainly for 800-900+ hp engines and mines gonna be around 520. he told me it would be easier and more practical to go with a holley or edelbrock for what im doing

[ProdigyCustoms]

i talked to someone at prodigy and they said it was mainly for 800-900+ hp engines and mines gonna be around 520.

I do not want the facts confused, I am sure you are just generalizing to keep the answer short. What I said was your combo is mellow and the Holley should work just fine on a mild combo IF you have a tuner that knows the system. The FAST is a better choice if the motor has Big stupid cams (Like Project Prodigy) or forced induction where advanced tuning capabilities are required. Horsepower has nothing to do with the decision.

The FAST may be overkill for you project, but this is a community FULL of overkill, LOL!

[Matt H.]

ya i just shortened what you said. i have someone who can tune both the holley and the edelbrock systems so its between those 2. Ando although i overkill on a lot of things, the FAST system is very expensive and i think its really more than i need

[PRRC]

Matt, Not sure if you've made up your mind yet.But We would sure like to give you a price on either system.I think we could save you a few bucks. Thanks Tim / Paradise Road rod & custom

[Z-man]

IMO - the Holley is a great system and would be an excellent choice. Of course, I'm running one. I also use a wide band O2 sensor. I'd recommend one if you go EFI... :)

[Slow Ride]

What about megasquirt for us poor bastards? How cheaply could you put one together for a big block with the possibility of adding a turbo or 2???

[Fracture Critical]

neat thread!

ok, here's what I know for sure, some of what I've figured out over the years, and some stuff I'm just guessing at:

if you're going to go to EFI, which is a big ticket item, then do it right and get a proper manifold. the TBI systems out there, even the multi port systems out there are not ideal for EFI. those systems are based on manifolds for carbs, so they're designed to take the intake air charge when it's wet with fuel, and get it to the intake ports as expediently as possible without causing the fuel to precipitate out of the air charge on the way there. by going to EFI that uses a manifold like this, you're basically looking at just increasing the efficiency of the engine and eliminating the carb.

auto designers realized that by going to a port injected configuration, they were released from the need to design manifolds that had to be able to keep the fuel suspended in the air charge. the air charge was now 'dry', and by using long runners, the air charge could be accellerated at lower rpm and 'ram' the air into the heads via the air's own inertia. furthermore, a large plenum helped act as a reservior for the runners, no matter the throttle position, and that helped the area under the torque curved, as well. any modern fuel injected engine will use this type of manifold. if you ever get the chance to look at a Taurus SHO motor, it is a piece of art in this respect. it actually has two set of runners to each cylinder. a long runner for low end torque and a short runner for full throttle blast.

wiht that said, the best way to get the bang for your buck out of EFI is to find a dedicated EFI manifold for your engine. if you can't do that, then the next best thing is to have someone like Hogan's build you a manifold for your application, but that's a $3k expenditure. (ouch)

lastly, I don't want to hear anyone bashing megasqurt until you read the megamanual. it's really the best bang for the buck out there, assuming you are willing and interested to learn EVERYTHING about EFI. if you're a plug-and-play guy, it's probably not for you.

oh, HI by the way! I' ma new guy here ;)

[BB69]

I was reading through the older threads, and saw this one. I just completed putting fuel injection on my big block Corvette earlier this year. I am still in the tuning stages, but thought I would post some pics and information. I used a port manifold and fuel rails from Holley.

http://i44.photobucket.com/albums/f25/grulich69/Corvette%20Fuel%20Injection/PICT0112.jpg

The computer is a Megasquirt, and I am using it for fuel and ignition. The ignition is handled by the Ford EDIS distributorless ignition.

http://i44.photobucket.com/albums/f25/grulich69/Corvette%20Fuel%20Injection/PICT0383.jpg

http://i44.photobucket.com/albums/f25/grulich69/Corvette%20Fuel%20Injection/PICT0104-1.jpg

http://i44.photobucket.com/albums/f25/grulich69/Corvette%20Fuel%20Injection/PICT0103-1.jpg

The throttle body comes from www.auto-nomics.com and is very reasonably priced. It was originally used for a fuel injection system that had the injectors under the throttle blades. However, Auto Nomics sells machined plugs that allows it to be used as a throttle body only. I also bought the wiring harness and fuel pump from Auto Nomics.

The system works better than I could have hoped for. So far, I have only had a few problems. 1. I think I screwed up when installing the new intake manifold gasket as I am getting smoke from the exhaust and fouled plugs. I will be replacing the manifold gaskets this coming week. 2. I bought a wideband O2 sensor from Innovate. It stopped working during the initial setup. Innovate fixed it under warranty no questions asked and it now works fine. 3. My old laptop with a serial port finally died, so I had to buy a USB-serial adaptor for the new computer. The adaptor works well, but it did cause Megasquirt to lockup once. There is a published fix for this.

As I said, I am still tuning (which is hampered by the oil leak) but I have run one track day in addition to my street driving with no fuel injection related problems. I am also using the extra output of Megasquirt to control my electric fans. I can turn the fans on and off at any temp, and I can also combine this with engine RPM (or any of a bunch of other factors) so the fans don't come on when the engine is cranking.

Ken

[kennyd]

we are using FAST XFI on a few cars in our shop . i really like the system so far , we are having some set-up and programming problems , like cold start , and timming set up while cranking , but this system will allow adjustment to your needs .
the system has so many functions that you can eliminate in the start , AFTER that you can wire a complete XFI in less that 6 hrs . the wiring harness that we use is a standard cut to fit harness , so you can shrink wrap each sensor or bundle instead of using the split loom that they send .

if i have any problems with FAST it is that they need a better viedo to watch and learn what screen controlls what . they go thru the viedo like you have been using XFI for years .

[rocketman]

I've had FAST on 2 car's it's a great set-up.

[andrewmp6]

id talk to http://www.mass-floefi.com/ or http://www.retrotekspeed.com/

[whytry]

Hey Matt, what did you deicde on and why?