FI Tech "Go EFI 4" Self Tuning Throttle Body Injection Install Thread

All,

Thanks for the feedback and support. Still waiting for my call back from FI TECH today......zzzzzzzzzzzzzzzzz.....

I am 100% certain it is a fuel delivery issue from the FCC at this point. This is the video I had to send them to convince it was a FCC issue.

Run starts at 1:10. As you can see, low side pressure is fine. High side pressure is dropping to nothing. The fuel commander IS NOT running out of fuel. For some reason, it is not able to get fuel from my FCC to my TB. Has to be an internal pump problem, or a venting/vapor lock problem.
https://www.youtube.com/watch?v=TcrKeua5ipM&feature=youtu.be

To summarize all that I have done over the last ~ 3 months to try and solve this issue (recall, when this issue first started, it was very intermittent and hard to troubleshoot, now is constant at WOT). I eventually thought the issue was temperature related, because when I would take my car out for a run and it was still not at full temp, in the 165-180 range, it ran fine. As soon as it was at full temp, it would start nosing over again or stalling out at higher rpm. I now realize this could be to the FCC venting issue and a build up of liquid/pressure that prevents fuel delivery. Eventually, the problem became chronic, and it would never complete a full run.

-Dropped my gas tank to make sure my pick up sock was not collapsing. At that time, I took the opportunity to replace my gas tank, pick up, and installed holley hydramat rather than a pick up sock. Ensured no fuel supply issue at tank.
-Replaced supply fuel line from gas tank to metal hard line
-Verified the intermediate rubber line on frame (4 inch section on GM A bodies) was in good shape. (I had replace this in the last few years, it was good, not spongy, no chance of collapse).
-Inspected my hard lines from tank to pump to verify no signs of leakage
-Replaced my rubber supply line from my hard line to my mechanical fuel pump
-Replaced my RobbMC mechanical pump with a spare known good TA Performance pump. To be safe, sent my RobbMC pump to them for inspection. They inspected, said all was fine, but rebuilt anyway and tested to be safe. I have since installed this pump back on the car.
-Verified I have good low side fuel pressure up to fuel command center.
-Grounded EFI TB directly to negative battery terminal
-Adjusted throttle position at WOT to achieve at least 95% TPS.
-Ran a new supply line from the fuel command center to the TB.
-Ran ground directly from fuel command center to negative battery terminal
-Verified my tach signal to the EFI TB is running in a separate shielded wire loom away from MSD box wires to avoid any interferance
-Installed a known good, almost new MSD ready to run distributor and new coil and took tach signal directly from distributor to try and eliminate ignition system issues.
-Ran new vent line from fuel command center all the way back to gas tank (previously had it terminating into factory vent vapor line in engine compartment, was worried it was actually pressurizing FCC tank).

I ordered my powersurge from RobbMC today. I KNOW....I would normally go with the Tanks Inc set up, but I recently spent so much on my Robb MC rebuilt pump, new gas tank, custom made pick up, and holley hydramat that I REALLY don't want to abandone that set up. I also want to use the powersurge to finally prove it is THEIR FCC design/issue. If that still doesn't work, I will just buy the Tanks Inc set up and move this existing gas tank to my other GS.

 

Wow Eric. And everyone says I have a lot of patience...I feel your pain. Feel free to use me and my car's issues if/when they call back. There's a guy on www.corvetteforum.com as well....exact same issues as you and I....yet they still deny it's an issue on their end...heck, I'm pissed just reading yours...lol.

I'm curious why you went as far as replacing the tank, but not just getting an efi tank at that point? But....I also fully understand going as far as you did , and not tossing in the towel...it's a catch 22.

I am very much looking forward to your results with the Robbmc surge tank.

I drove mine home today, then took a nice abusive ride, to take it back to shop...never missed a beat.

I'm sure you posted this, but how does the car run, normally? Just cruising around? Curious more than anything.

 

I know it's bought, but is the surge tank necessary with the hydramat? I AM skeptical of the claims, but I thought one of the claims was you don't need a sump when you use it, and if you don't need a sump you don't need a surge tank.

 

I have been following this since the start. I want to do this to my 70. I like the idea of the sump up front, but the issues with the FI tech one isn't very appealing. I start to look and see what else is available and found this http://www.edelbrock.com/automotive/mc/efi/fuel-kits.shtml
This looks like it might work better. Haven't seen a price as of yet. Any thoughts?
Thanks Rick

Just found a price at Jegs, ZOWY almost 600.00 for just the sump setup.

 

No, not necessary. I was trying to eliminate any possibility of fuel starvation to the FCC. Waste of time and money.

 

I've been guilty of taking a sledge hammer approach to frustrating problems too. Carry on! :beer

 

Well, hindsight being 20/20, I should have just replaced with a Tanks EFI tank right then. It was early in the troubleshooting process and I was working under the model that the FCC was fine....."either works or not"....so I did this. Once I dropped the tank to check the sock, I decided to replace the tank because it was 40+ yrs old, crusty, rusty, scratched, and a new one would look nice. Then that snowballed into the hydramat mod.......it wasn't until 2 weeks later I found the Tanks inc set up and thought "crap, I should have just done that!" I had this mental model that an EFI tank was very expensive......from when I looked at them a few years ago....not so much anymore.

The car runs fantastic at cruise/part throttle, and idle. For that matter, when the FCC works at WOT it runs fantastic also. I had a reasonably tuned 800cfm Q jet on previously. I never would have guessed the improvement in throttle response with the FI. Idle at stop lights smoothed out. Rolling burn outs up to 40mph are effortless now. Prior to this, my issue was that I thought I needed a higher stall converter to ease idle at a stop and help me get into my torque band. After the conversion, aside from the FCC, my biggest issue is traction now. I see a set of drag radials in my future .

I am encouraged about the RobbMC powersurge. It was cool to talk to the guy at RobbMC and find out the FI Tech/powersurge set up is exactly what he runs on his personal vehicle. The set up is simple, similar to the FI FCC, but you run a return line from the TB back to the powersurge. No need for a regulator because the FI TB is already internally regulated. I can just reuse my existing feed line.

 

I think the eddy unit is good. I looked at them in detail a few years ago at SEMA when they came out. Also looked at them again when looking at my options to deal with this mess. It is just the price that keeps me from it. The dimensions are a little weird also. The RobbMC powersurge for similar performance is $299. Dual pump, 1000hp capable is $399.

 

SilverBuick, I have read your other posts. The stuff you do is awesome. I do not see much evidence of a sledgehammer....you must hide it well. Wish I lived closer to you.....would love to see the work you do in person and learn something from you.

 

Thank you for the compliment, I must p


I'm an experimenter, and thus a troubleshooter, at heart so things drive me up the wall when I cannot find/see a root cause. If you are ever in Ely, stop on by!

 

Can you guys put together the ultimate parts list for a reliable system and post it please? Trying to piece it together from the thread but a tad confused. Don't want to reinvent what you guys have already done the legwork on. Sounds like you're getting it down. Or maybe I'm lazy.

I'll be getting the FI 800HP unit but not the (planned) FCC for obvious reasons.

So far my list is only the FI unit and the Tanks, Inc tank for '70 Buick.
Will my mechanical pump go away and do I need an electric EFI pump now that the FCC won't be in the circuit (answer to one answers the other I guess)? What's the pump of choice?
Where do I need to run return with the above parts?
Of course I know I'll need fuel line and fittings.
What should be used for a filter? I have a Mallory 140 filter for carb but not finding an element. Probably need a better filter for EFI so hoping the elements might interchange and save me a couple hundred bucks on a complete unit.

Add to the list if needed. And thank you for all the beta testing!

If I get this set up and running properly I'll cruise to Ely from Elko just to take a ride.

 

I'm replying mostly to subscribe to the thread, since I didn't see a way to do that without posting in it.

I have a FCC sitting in my dining room waiting for the throttle body (EFI Go 600hp) to arrive. I've been going through carbs on my 79 Vette (Edelbrock carb had a stumble when the secondaries opened, and now the Holley I installed in October and ran perfectly all winter is percolating like crazy while I'm driving now that it's warmed up and the A/C is on) and need to buy a carb for another car I'm working on. I figured I'd try the EFI on my Vette and use the carb that's on it for the other car. If things go well with the FiTech EFI on my Vette, I might also put it on my 72 GS455 clone, as those cars are my daily drivers.

I love the idea of the sump tank, but all of the issues people are having with the FCC is disheartening. I'm very curious to see how the PowerSurge will perform. Before I bought my Holley, I was considering the Edelbrock EFI with their sump, but at around $2500 for the whole setup, I figured a $550 Holley carb was worth a shot.

I'm glad I bought my FiTech setup form Summit, as their return policy has been pretty lenient in my experience. If I end up having the same troubles with the FCC, Summit will get it back, and I'll check here to see what ended up working for everyone.

I've also been following the threads on the corvetteforum site and the Chevelle site. Thanks to all the early adopters that are sharing their experiences so the rest of us can benefit!

 

Never stated anything about the vent vs bowl filling...only that the carb will cease to function without it. :TU:

It appears the RobbMc surge tank is identical to the FCC with the exception they must have solved the vent problem. It does use a vent that must return to the tank and is only 1/4" in size.

 

The TanksInc setup has your choice of a GPA-4 (630hp), or a GPA-6 pump (500-900hp).
http://www.tanksinc.com/index.cfm/page/ptype=product/product_id=227/mode=prod/prd227.htm

I'm realistically at 550hp at the crank, so I chose the GPA-4 pump in the TanksInc. tank options.
You'll need TWO 1/4" NPT to -6AN adapters, which will connect intank pump to your feed and return lines.
http://www.summitracing.com/parts/aer-fbm5004

Regardless of whether you choose to use pushlock or traditional braided stainless, will dictate which type fittings you use, but sizes are the same as here:
FOUR straight -6AN fittings (2 for gas tank end of feed and return lines, and one for each side of filter
One 10-30micron inline -6 filter (I used this one: http://www.summitracing.com/parts/fif-80112/overview/ )
TWO -6 90 degree fittings for throttle body ends of feed and return

The tank came with a new vent system, a "T", and a rollover valve. Just need a couple feet of 5/16" hose and put where it'll fit, basically.

I use the FiTech throttle body to power my fuel pump, and simply extended wiring back to the tank.

You basically need about 28 feet of -6 hose to do both lines, but in bulk, I've only seen it in 10 or 20 feet lengths...so you're kinda screwed there.
You'll have to either buy locally, from someone who can sell it by the foot, or buy TWO 20' sections...

I chose and even easier route.
- I have 3/8" EFI hose, using pushlock fitting from PUMP, secured with EFI specific clamps, to factory 3/8" steel tubing (less than a foot away)
- 3/8" EFI hose, again efi clamped to exit end of factory 3/8" tubing, up to inline -6 30 micron filter, to a pushlock 90, at the throttle body
RETURN, is a 90 at the throttle body, one piece of EFI 3/8" hose all the way back to the tank, and a -6 pushlock

I kept all the pushlock fittings, filter and hose from the FiTech Fuel Command Center, so my fuel "system" cost me roughly a hundred bucks, which was mainly for the 15 feet of EFI hose bought locally.

That's what I have, works great, but part numbers are yours to find.

FWIW, Summit right now has 10% all AeroQuip, so I am considering going with the stainless braided lines, just for peace of mind...
If I do go that route, I'll share the part numbers used...

I would all but guarantee that if your carb is percolating, then the FCC definitely will be a thorn in your side.
They claimed mine was boiling over, on a less than 60 degree day, with the coolant at 170 degrees, and less than a 4 mile drive...ironically, the carb NEVER percolated, even on 100 degree days, with near 200 degree coolant temps and my AC on...

Just a head's up...

 

You might consider PTFE hose. Will never have to replace it. http://www.summitracing.com/search/...=ptfe hose&N=4294924175+4294920957+4294920508

 

:tu:

 

Changed my mind.....I think I will order in the Tanks inc gas tank, sender, and GPA-6 pump, rather than the powersurge.

I think the powersurge would work, and have confidence in RobbMC products, but am sick of experimenting and being without my car to drive......so going to install something that has a better proof of success.

http://www.tanksinc.com/index.cfm/p...t_id=381/category_id=102/mode=prod/prd381.htm

 

Got mine installed today Eric...need to fabricate a bracket to hold the filter and rollover valve.

 

My parts got here today



Should be back on the road by this weekend.

Questions:

I talked to tanks inc today about using the factory vent lines vs using their rollover valve vent system. they said with a vented gas cap I should be fine using the factory vent lines. I think I will just tie into the one that originally went to the center of the stock gas tank and cap off the other two? Sound ok?

Also, how much pressure and volume go through the return line? Any reason the factory 1/4 return line originally for the carb isn't sufficient?


Found a pretty good post on the camaro forum about a similar install. http://www.camaros.net/forums/33-camaro-tech/263481-tanks-inc-efi-fuel-system-install.html.

 

I also had the 3 vent lines on my stock tank, but chose to use their 2 into 1 vent system.
I have it looping up over the driver's side of the tank, and secured up behind the rollpan or whatever it's called.

I didn't want to risk using the 1/4" vapor/return line, so ran a completely new EFI rated rubber 3/8" return, and used the factory 3/8" steel line as my feed.
I also have a vented cap, as I definitely did not want any more venting issues...lol.
Works very well.

I'd also HIGHLY recommend using their CORK GASKETS for the sending unit and pump...I did everything exactly as they said to, even searching for and finding Indian Head Shellac sealer, and 1st fill up, they both weeped a little gas...

http://www.tanksinc.com/index.cfm/p...t_id=100/category_id=167/mode=prod/prd100.htm

I'm not happy I'll have to pull the tank down again in the near future...especially since the straps they supplied are very flimsy, soft metal and bent up on the ends when tightened.

The tank, pump and sending unit all look and work very well though.

I actually went to the dragstrip finally, on Wednesday evening.

Ran 1 mph faster than ever, and a couple hundredths quicker. 11.75@115 EFI'd (1st pass) vs. 11.77@114 Carb'd (best ever)
No big deal, right?

Well weather was better on the carburetored runs, and I usually have a half tank of gas, but it was full the other day.
Also the WOT AFR was actually very rich, like mid 11:1 rich, which I think is because the ECM "learned" WOT with the lame FiTech Fuel Command Center, and kept dumping fuel, trying to compensate for no fuel being there, and now that the supply issue is fixed once and for all, it's needing and trying to learn around that...At least that's my theory, lol.

This is also with 28" tall drag radials and 3.08 gears...Car's been 11.31@117 with 4.10's, so I'm 100% sure it'll go 11.20's as is, with a gear swap, but am getting used to the 3.08's...I must really be getting old...lol.