Fast ez-efi

[Steve1968LS2]

We just did an install with Street Rodder on this.

The tech was very impressed with how easily it went on and how it "tuned itself"

I'm going tomorrow to check it out.

[Motown 454]

Steve can you find out if their going to make a system for over 550 hp.?

[JustinB]

Steve can you find out if their going to make a system for over 550 hp.?

Check a couple post up. I read thru the instuctions on thier website and it looks like it will support up to 650 hp if you increase the injectors flow rate up to 60 psi. It also looks like you can run a dual setup and it would support 1100-1300 hp. States pretty clearly that it is for N/A applications only so you forced induction guys are SOL. Would like to see some more feedback from users before I raid the pennybank but so far it looks like a pretty cool kit.

[68Formula]

I'm not sure how the self-tuning mode would work with two of them. I'd think they'd be chasing each other trying to correct the fueling.

[1969CamaroRS]

I'm not sure how the self-tuning mode would work with two of them. I'd think they'd be chasing each other trying to correct the fueling.

I think you would get one tuned at idle then add the second, then go back to the first and reprogram. Same deal with the other circuits. Definitely an interesting system with a great price point.

[68Formula]

I think you would get one tuned at idle then add the second, then go back to the first and reprogram. Same deal with the other circuits. Definitely an interesting system with a great price point.

It tunes itself using feedback from the wideband O2. When you put on the second one, the IACs are going to try to close simultaneously to correct the idle speed, overshoot too low, overshoot fast etc. Even with one IAC disconnected, fuel correction would do the same overshoot lean and then rich, never stabilizing.

Same with part throttle and WOT. Even if one has all the sensors disconnected except for O2 (assuming also this would not cause a limp home error mode), both are going to try to add or pull out fuel about the same time and then recorrect by adding fuel at the same time.

Unless they are designed to talk to each other so you have one correcting at a time until equilibrium is reached, I don't see you getting a stable response. It would have to be manually tuned for all circuits including accleration enrichment. Or one would use an ECU, and somehow it needs to trigger the injector drivers for the second throttle body.

Anyway, for the cost of two, you could put on a multiport system with two throttle bodies (and one ECU)

[Hammered]

I wonder if you could put one into open loop with a rough tune and then let the other fill in the missing fuel? Not optimal IMO, but it seems possible.

[1969CamaroRS]

Perhaps we are over thinking it. At part throttle and idle, I'm sure one unit could offer enough air fuel. Perhaps the second unit could be put into a "slave" mode and only enrichen when at WOT or near. I'm assuming you would only need the extra fuel if you have exceeded the ability of one unit to provide the fuel. The first unit is trying to put out as much fuel as possible then the second kicks when the 1st is at 100%.

But good point at the price, probably not an appealing solution unless you already have a dual carb intake and really just wanted a TBI.

[JustinB]

I wonder what kind of throttle response you would get with this TBI unit. I am assuming it would similar to a carb setup considering the postion of the injectors. Someone buy this and let me know if it is worth please!

[68Formula]

It would depend on the carb size your comparing it to, the booster type, and the manifold type.

A mild carb (say for example a 600cfm on a 350), with dogleg or annular boosters, and a dual plane would probably be close. A single plane and large carb (say a 750cfm) with straight boosters the TBI would have better response.

[DaveC3R]

The only input I have is don't waste your money and time on Edelbrock EFI... I really wanted the system to work... and I really worked it for over a year. I got it running, with no help from Edelbrock Tech despite lots of calls and on-hold time... took me several months. First problem was it shipped to me with a hole in the regulator diaphram, took weeks to diagnose... lots of hold time. Next was a sensor, then another, then a problem with the distributor, and on and on. No pro shops that know anything within 500 miles of me, so I became much more educated in the thing than I had any intention of. I lived with it for as long as I could and then put a BG Speed Demon carb on and I've been driving and enjoying my car since. Sorry for the rant, just venting.

[JustinB]

It would depend on the carb size your comparing it to, the booster type, and the manifold type.

A mild carb (say for example a 600cfm on a 350), with dogleg or annular boosters, and a dual plane would probably be close. A single plane and large carb (say a 750cfm) with straight boosters the TBI would have better response.

Current setup is a Edelbrock Victor single plane with a 1050 Dominator. A little better throttle response would be nice.

[1969CamaroRS]

I would think with a Speed density TBI system that its main advantage over a Carb would be the ease of cold starting and responding to changes in altitude. Not sure it would have the same throttle response a MPFI system (especially SEFI) would have due to wet intake vs dry and not metering a precise amount of fuel right to each cylinder.

Probably a lot quicker to get this system tuned properly than say the time it would take to tune a carb. But assuming both where tuned well, not sure there would be a lot of difference.

[Vegas69]

TBI is still old technology. Not near as old as carburation however. If I go to injection I want each cylinder being fed at the cylinder head. That way you can tune each cylinder to it's potential. I was talking to an old timer yesterday about stagger jetting in a carb. He runs in the 6's in the quarter so I have reason to believe him. He mentioned with small block and big block firing order, cylinder 5 and 7 share teh same intake runner and fire after on another. He told me to add two jet sizes to that rear jet and I'd pick up horsepower. Can't be any different with injection. A minor deal but just wanted to point out the difference between direct and tbi injection.

[EricW]

I'm thinking about getting this for my nova. I have run modified GM TBI set ups before and yes TBI has its problems like with only 4 injectors the system is RPM limited do to 1 injector needs to fuel for 2 cylinders so it has to stay open longer, higher the RPM the less time it has to stay open vs 1 injector for every intake port. You have the same problems with any wet flow system like fuel falling out and collecting on the walls and floor uneven runners ect. Some high points is that TBI is way more friendly to single plain intakes than carbs as it does not have to worry about low speed vacuum problems. More MPG than a carb better starting and cold motor operation and is self adjusting. As far as Dual TBI system I would think it would run like every other Dual TBI system I have ever seen just 4 more injector drivers on the computer and only one TPS and IAC on one TBI and no progressive linkages.

A tunnel ram with dual TBI's would be sweet looking. Alittle over the top for me but what is a pain to get right with carbs would be a breeze with a self tuning TBI system.

But the real up side to TBI is a cheap entry price to EFI.

[qwk406]

Spoke to Cody at retrotek today, he says the powerjection 3 system will handle 21psi of boost, needs a return line, has wideband O2, a 2.5 bar MAP, all electronics are contained in the housing, uses GM sending units, Bosch O2 sensor and is complete except for fuel lines for $1650.00. Not bad for injection! I like the simplicity and the fact that the car will run cleaner. When I'm cruising on the highway the fumes take their toll and I have full exhaust that has NO leaks. I get out of the car and I stink. Tuned and re-tuned, just don't have the adjustability that F.I. has. If I decide to go this route I'll let you know how it works.

[lnirenberg]

I'm using this system on my 409--
http://www.mass-floefi.com/mass-flo.html

It isn't built yet because it requires a single plane aluminum intake which has never been made for the 409 but one is being developed by one of the 409 gurus in Alberta. I hope to have it up and running before the car hibernates for the winter and I will post pics, dyno results, fuel economy comparisons (currently has dual edelbrocks) and general impressions when it is done.