Anyone used Holley projection fuel injection??

Discussion in 'Classic Mustang Specific Tech' started by 84convertablegt, May 31, 2005.

  1. Just wondering if anyone has used the holley 2bbl or 4bbl pro jection electronic fuel injection on there car? it seems like a really easy install since it doesnt even involve changing the intake. basically its a steroids throttle body fuel injection. its just a cheaper route than multi port, im looking for experiences with it, power compared to a carbed setup, etc. basically im thinking i want fuel injection for the quick starts, etc. but i want the look of old school carb without the late model intakes, etc.
  2. I asked this question a while back and didn't get much of a response so I'll chime in. I was looking at it for the same reason you are. From what I gather it's not a bad system. As far as how well it will perform on a modified engine I'm not sure of that. You might want to look at talk to the people at Holley for that one. You can find some nice setups on Ebay and at a pretty good price too. If someone has more knowledge of this system please jump in cuz I would like to know more about it as well
  3. i plan on running the commander 950 TBI setup on mine with the TFI style distributor. they aren't as good as multi-port but are better than a carb for a driven car, if you want a ful race car it may not be the best choice however.

    a carb will make more max power than a TBI unit will but the driveability of the TBI setup is infinitely better than a carb, especially a carb that has not been super tuned.

    you can get close the driveability of fuel injection with a carb or you can get maxpower out of it, but not both. with the TBI setup you can get a better overall compromise of performance, drivability and economy than you can with a carb, but still not as good as multi-port.

    all that said the TBI system is a good middle point between car and multi-port and holley pretty much has the market cornered on that
  4. Megasquirt...alternative to Holley

    Cant say I have alot of info in the Holly setup but I can tell you that I am quite impressed with my current megasquirt system. Also, a lot of old holley users are now on this system.

    Take a look and enjoy.

    There is a great user community for it at

  5. yeah, but that looks like its just for the software controller side of things. im talking about a whole system here... on another note, i dont want to lose performance going to the TBI system. i currently have a holley s.a. 670 carb and the car is powerful. if i lose performane i dont think it will be worth it. isnt TBI basically just kind of like a carbureator with a electronic brain to control it?
  6. Avoid it.

    We put it on a 71 f100 over two years ago and the truck never moved under it's own power. It ran a little rough before, but the carb was junk so we thought the pro-jection would make it run smoother, cleaner and get better fuel economy. We took it off after we messed with it for about a year and a half. :bang: We only had time to work on that truck about once a month for half a day or so, but it still never ran for more than about 5 minutes at a time and never made it out of the garage. We put a new carb on it and it fired right up.

    I know where you can get two sets cheap if you want them, but there are no guarantees that your vehicle will run with it. :notnice:
  7. You are correct that it is just the electronics and tuning software but the system is flexible enough to use just about any Fuel injection hardware you want, anything from the stock 5.0 mustang multi-port FI hardware to the Holley hardware. The choice is yours as to what hardware to use. Most people that complain about the Holley system say they have a hard time tuning it and that is all in the brain and software. There is nothing wrong with the holly hardware. It works fine and has been proven as there are several people that have ditched the Holley computer and replaced it with Megasquirt. In all actuality the Holley system uses mostly General motors hardware ;-)

    As far as the EFI stuff goes the TBI is mounted just like a carb and does have the same difficulties associated with a carb as far as fuel pooling in the intake and such. The advantage you will get with The TBI will be a smoother idle if you have low vacuum signal due to a radical cam. Also, No MORE TUNING A CARB! WAHOOO!!!!

    Overall there are pros and cons for both systems. Most people believe that a Carb system will produce more peak HP than FI. And they would be correct but unless you are trying to get every last ounce of power out of the car and used a dyno I doubt you would notice the difference in the top end.

    Now if you go with a MPFI system like the 5.0 mustang system you will give up a little bit of power in the top end but you will gain a TON of torque in the bottom end. This is because the intake system is a dry system with MPFI and you can run long intake tracks to improve your low end throttle response and torque because the fuel will not pool up in the intake. This is the greatest advantage for our cars as I very rarely break into 6000 RPM. I spend most of my time down in the low end and torque makes the light little mustangs FUN to DRIVE!

    The Megasquirt system can control both TBI and MPFI and is very easy to tune for any engine configuration. There are several people that are getting 1000+ HP out of their race engines controlled by Megasquirt…yet they are still tame enough that they can drive them to the track.

    As a side note there are people that are using Megasquirt to Fuel inject some small 2 stroke motors so that should indicate the flexibility of the system.


  8. I used to have the Holley 670cfm, 2 bbl Pro-Jection system on my 302. The engine had the stock cam and heads and I replaced a 2 bbl carb and intake for the Pro-Jection system and an Edelbrock Performer intake.

    The system worked great and gave me much more power and better gas mileage over the the 2 bbl. It did take quite a while to get the installation up and running, but once it was dialed in it worked great.

    After I swapped the cam, heads and intake for more performance, the 670 system couldn't keep up with the engine and I had to go back to a 600cfm carb.

    I will definately go back to EFI on my next engine, but I will probably go with the Edelbrock Multi-point system -

  9. Rollinns,

    Sorry, but if you never got the car running, it sounds like installer error. The system works as long as the components are properly matched. Whether or not you like how they work is another thing.

  10. well if i could do it anyway, it would be the ededlbrock system probably, but it is 3 times more expensive than the holley tbi. well from what ive heard so far, i doubt ill do it. i dont drive the car that much anyway, i guess ill just tinker with the carb and wait on the choke :) for now. if the tbi worked as well performance wise as a carb, id probably do it, but i have my doubts. its obviously not the best route, thats why multi port efi was invented i suppose. tbi is old tech, probably not worth 900 dollars now
  11. I too have been looking at a fuel injection setup for a couple of projects I have going. I will be going megasquirt as well, havent built it yet but it is definatly the way I want to go. From their fourms I have noticed that it is much better to use then the commander 950 this is from what I read not first hand info. I trying to wait it out for the version 3.0 main board with some upgrades that are worth waiting for. Very cool stuff!!!!

  12. I love my Megasquirt, Works well. I am currently in the middle of completely ditching the distributor and going Distributorless with the Megasquirt.

    65 Fastback, That is the beauty of the Megasquirt. If you upgrade your engine…slap in some larger injectors and spend about 30 min to retune and you are golden!

    84convertablegt, Don’t let my earlier comments about TPI stop you from doing a conversion. You will get excellent drivability from a TPI setup and an excellent amount of torque. You might loose about 5 Peak HP but the gains in drivability and overall torque increase make it all worth while.

    Also…my MPFI system cost me about $450.00 (including the cost of the Megasquirt) and some sweat equity. That is it. and I got a rebuildable 5.0 roller block out of the deal as well (it actually runs quite well but it did have 88K miles on it).

  13. We also ran it in our mach when I had it. Here's my notes from when I had my website.

  14. You know people always talk about how great fuel injection is, but carbs work and are so much cheaper than any EFI system I've seen on the market that it makes it hard for me, anyway, to justify upgrading technology.

    For a 302 you could build a multi point injection system for not to much money, because of the availibility of parts.

    I've got a 351W so I would have to spend at least 400 on a new intake before I even got into buying injectors and the other stuff needed.

    Of course I might be able to put a TBI system together using the megasquirt controler for under 600. Well it is something to think about. Rufusbooth thanks for the info.
  15. No problem…I am not knocking carbs they have their place.

    I personally am so fed up with carbs and their quirks and retuning them each season change. It is just a pain in the butt. I run from the valley floor of 28 feet to 7000 feet about every other weekend and the carb was just too much to deal with. The carb could be tuned for low or high but never both. The Fuel injection allows me to have a good tune at any altitude or temp.

    I personally have vowed to never own another carb again but that is my own choice. I have converted several vehicles to FI just for the reliability and ability to pass California smog without batting an eye every time.

    Every person needs to evaluate their own personal needs and if FI is for them.



  16. I can understand why you would think it was an installer error, since there are so many people who have successfully used this system. I do know how TBI works, and I have a working MPFI system on my car. We have talked to many people about this and for every person we talked to who recommended it, there were two mechanics who avoided it. We also bought both systems used and had to go back through the wiring to correct some of the previous owners "modifications". The comment on properly matched components is likely the culprit since the fuel pumps in both systems were unusable and we replaced it with a late 80's GM TBI fuel pump which may have been to blame. Either way we are pleased, he has a running truck with a carb, which he likes better and I have a running car with EFI which I like better.
  17. Here Is My Commander 950 21 S

    Its almost finished, runs great, took some time to tune.
  18. is that the 4bbl model? i wonder if it works alot better than the 2bbl, besides the increased hp potential.
  19. Its the largest 4bbl they make till you go with duels. alsome throttle responce to. If you get one, go for the Wide band oxygen sensor, it makes tuning a lot faster.
  20. commander 950 maps

    I would be interested in a Commander 950 mpi map for a 351 cleveland...Mine runs well but I have acceleration bog...due to the accelerator map not being quite right and would be interested in comparing notes.......HGWells