rip74

Thanks for the response!

whizkidder

Two schools of thought on vacuum advance. I'm using ported vacuum (used to be hooked to the vacuum can on the dizzy, now to a 1-Bar MAP sensor for my programmable MSD 6AL-2). Since you should not have any vacuum at WOT (as when on the dyno), don't believe timing is the problem.

c3_dk

I am almost done mounting EZ-EFI in my 1969 Corvette.
I've replaced the std. intake/carburetor, with a Edelbrock 2701. I can see that I need a new throttle bracket, what throttle bracket must I buy, when I have my std. speeder cable?

fauxrs

almost 3 months since last CARB update - any news?

(sincerely - the OTHER CA pest)

Shark Racer

17.5 mpg with a q-jet. I wanna go for 20+.

baxsom

Has anyone else had problems with the computer on these things. The shop that did my crate motor install used to install these but after getting 3 in a row with bad computers they quit using FAST and went back to the holley TPI. FAST did send new control units for each kit but for some reason everyone of them were bad. They did like 10 total. 7 went in perfect but the last 3 just crapped out.

KJL

Any Updates? I really don't care about fuel economy. I cringe a bit when I hear people talking about how many MPG they are up to. They should just buy a Prius and be done with it. I haven't read every post in this thread but I am interested in hearing from those folks that have switched from a carb to a TPI or MPI system and if they had improved power and torque at the lower rpm range as well as throttle response. Is there a significant diff between TPI and MPI other than cost.

TopGunn

Me too buddy! I'm gonna make up a tripower setup this winter just so I can smell the raw gas! This FI is too high tech. and too $$$

Curby

I changed the dizzy vacuum advance to the rear (actual) vacuum port on the throttle body. I also replaced my MOROSO 8MM wired with some MSD 8.5 MM wires. I have not been to the drag strip or dyno since I did this, but the car seems to be running fine. As soon as I get some $$, I will be getting the programmable MSD-6AL and do away with the mechanical advance and vacuum canister advance. This should give me the flexibility to program my advance curve to make optimal power.

The fuel mileage really helps when I am driving my 39 year old Vette with a big group of C5's and C6's on long trips. I can hold out as long as any 60+ year old bladder, now.

I am struggling with a small exhaust leak at my headers that is throwing off my O2 levels and causing a fluctuating idle, but I have a new set of exhaust gaskets that should take care of that issue.

The computer is fine, and I have had no issues so far.

c3_dk

Where did you mount the 12v switched wire?

PuddleJumper

my only bitching complaint is there is no spreadbore type for this..

corvettedave383

Ive ordered up the fast xfi, with the traction control ecu, I will let you guys know how it goes soon

dave

Curby

My car had the MSD ignition box on it when I got it. I used the same switched power that it is using. I tried the wiper motor wire, but it goes dead when the ignition switch is turned to the "start" position and it gave the computer fits trying to start and I basically flooded the car every time I tried to start it. Now it starts instantly.

71coupe

Do you have the vac advance line from your distributor hooked up to a full-time vac source? If so, try connecting it to the port that does not have a vacuum at idle.

baxsom

I think thats the first time anyone has suggested this method. I have always read here to do the opposite and connect to full vacuum to correct an idle issue.

bluzman2004

There is a port on the front of the throttle body specifically for the vacuum advance to be hooked to. If you connect the vacuum advance to manifold (full time) vacuum when your idle moves around the vacuum will too. Now your timing is moving around as well as the MAP sensor sees this and is changing the fuel, too. The the IAC motor is trying to lower or raise rpm to try and keep up. The whole system gets into a chase situation.

Billysvette

Let me play devils advocate,first i like the system but in my mind i cant put out over a thousand dollars for something that wont be a big seat of the pants difference,like a blower or turbo etc.From what i have been told ,there is no big difference in hp or performance,just alot better tuning,and runs smoother ,less tuning problems,a little better throttle response.Now tell the truth guys that have this system,is it worth it?And make the guys at work ,i work with,not know what they are talking about Do you think its worth that much $ or maybe half the price? FI i nice ,but i think they are too much $. compared to other performance gain parts in that price range.And remember,its already been proven that a carb will out perform FI in the 1/4 . Well,in magazines.Other then that FI runs best.Is that true? Just trying to justify the high cost of these systems,dont beat on me too bad just trying to understand ALL the benefits of these systems.I wonder how it would run on a blower .

MotorHead

Got 24mpg on the highway @ 80mph with my 550HP 406ci in OD, tuned properly with an LM-1. Going to do the same test soon on my 427ci, expecting over 20mpg. No need for FI for me, tune the carb properly and put in an OD transmission

Billysvette

Exactly what i mean ,in my mind the big money for this system doesnt justify it ,unless you want something different.Im just trying to find out about it.If i were to put down this money ,i better get a big old grin on my face when i run it ,like a blower or nos.

7t2vette

I started this thread, and I have had the EZ-EFI running on my car since the start of the driving season this year. I have had no problems or issues with it at all, my car runs awesome with it.

Was it worth it? That question has both subjective and objective answers.

In my opinion, carbs are a pain in the azz. I have an LM-1 air/fuel meter, and I used it to tune my carb. Once I learned how to use it, I was able to tune my carb pretty well, but not perfectly. That really annoyed me, because I like perfect, or as close as possible to it. You tune a few functions of carb, and others are not tuned. You tune the other funtions, and then the first ones you already tuned are now out of tune! When you tune a carb, it is a game of compromises. You can be happy with this, but have to live with that. When you tune a carb, it is tuned for the temp/humidity/barometric pressure of the day you tuned it. When those variables change, the tune changes, and a carb cannot completely adjust for them by itself.

With an efi system, the air/fuel ratio is constantly changed, in real time, as needed. No carb can do that, no matter how well you think you have it tuned. That's worth it.

I can watch all the parameters of the EZ-EFI system like coolant temp, throttle position, intake air temp, air/fuel ratio, rpm, battery voltage, ect, ect....in real time on the fly, even while I am driving, and I like that. That's worth it.

With the EZ-EFI system, I can change the idle speed, air/fuel ratio, rev limiter, ect, ect....on the fly, or even while I am driving with the handheld controller. Going on a long highway trip? I can change the cruise air/fuel ratio to as lean as my motor will stand after I get on the on ramp. Or before. Whenever I want without lifting the hood. That's worth it.

With the EZ-EFI system, I can change the temps that my electric fan operates on and off at without ever opening the hood. Not something that I'm likely to do very often, but I can do it if I want, and I like that. That's worth it.

When I get out of my car after a drive, I no longer reek of exhaust fumes, nor does my garage....and I don't run catalytic convertors. That's worth it.

I can start a dead cold motor thats been sitting for a week, and drive away immediately without an issue. That's worth it.

My throttle response and drivability are much improved, as is my mpg. I have a healthy 406 making 500+ hp. I went from 8-9mpg to 18+mpg, without an OD transmission. That's worth it. (on a side note, the Tremec TKO600 5spd goes in this winter for even better mpg! )

I like to be different, and have things that seperate my car from the rest of the herd. I also like and embrace new technology. There is also the coolness factor. That's worth it.

Now for the negative.

There is little or no hp/tq or performance gains, for a relatively high output of cash. If that's all you are looking for, then it's not worth it.


There is good reason why all modern cars use efi. Awesome power, awesome drivability, and awesome mpg. And that's a fact. I think alot more people would like to change their carbs to efi, but are either afraid of the technology, or can't afford it, or can't justify the cost of it. To tune a carb to the max, you need a good easily tuneable carb like a Holley HP, and an air/fuel meter, as well as all the tuning parts like jets, squirters, pump cams, air bleeds, ect, ect....which all bought brand new is WELL over $1000. BTW, my 750 cfm Holley HP carb, LM-1 air/fuel meter, and all my Holley tuning parts are now for sale.

And now for some gratuitous pics of my EZ-EFI system: