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

If you google "fitech efi" you will find several places with reviews and discussions but the chevelle site has more info than all of them put together. The FiTech system has overwhelmingly great reviews until you add the Fuel Control Center. As soon as you add it to the equation things go wonky. I've been really happy with my Meanstreet 800 FiTech and all I've done is driven it. There are some good bits of tuning info over at the chevelle site but I've concentrated on driving the car this year as long as nothing is broke. IF you have your heart set on using the FCC you'll see that at least a couple of people have gotten it working OK if they plumb it so that it vents/returns to the tank. This allows cool fuel to stay in the can and keeps you from pumping boiling fuel into the injection system. The other issues like the rear blades not opening 100% are again common issues and easily resolved just aggervating with a new purchase. The loose throttle plates (blades?) you mention is the first I've heard of though. Since the EZ-Efi and now the FiTech system you'd have to drag me kicking and screaming back to the carb. The F.I. starts right up on hot days, cold days and especially after a hot soak which always seemed to boil the fuel out of my carbs and force me to crank the car forever to clear the fuel. Good luck and read around at the chevelle site on some of the settings people are playing with in the pro tuning settings for the FiTech.

 

Pretty much what Ken said. Never liked the idea of a bucket of fuel under the hood.

Do not understand that you do not have good throttle response and power. I have had some really good carburetors and the FiTech blows them all away. Only thing that makes sense is the fuel feed is not correct.

 

well after fixing the few bugs i had i took it for a ride and supersized it ran pretty good , the only thing i seen out of the ordinary is when i move the throttle with nothing hooked to it i don't get 100 percent out of the tps just about 92.4 not sure if this is normal ??? but i think my biggest problem was with the throttle blades not opening at the same time off idle

 

My opinion-

Only a dyno can tell you this with any certainty. But with FI, you have the ability to adjust each point on the curve, so after every back-to-back run you should get a layover of the torque curves and see if a richer/leaner point on the curve might be the opposite of somewhere else on the curve. Your A/F ratio can be (slightly) RPM dependent, even after your VE curves are all dialed in.

Same with timing- I did many many dyno runs, and discovered that different parts of my torque curve liked different timing. That's one of the nice things about having a programmable torque curve instead of a fixed mechanical distributor.

 

My friend Bill's engine is an excellent example of this. Makes over 1,000HP naturally aspirated and they dialed in the timing at essentially 500rpm increments from 3,500rpm to 8,000rpm or so RPM and what his engine wants for timing goes up for a while, then drops ~2 for 1,500rpm or so, then wants more again. This work is done when you are in a highly competitive class looking for every bit of HP you can, but it does also show how non-linear, or fixed, these things are. The real bastard part of it is, that timing drop probably shifts up and down the rpm range based on atmospheric pressure, and there really isn't a good way to test for that with out even fancier dyno cell equipment. Also it seems, the longer you remain at a loaded rpm point the richer the engine wants to be to make power, both to cool the piston and valves and also the hotter cylinder can simply vaporize more fuel and get more power. Which is good info if you are in high gear by the 1/8 mile or have a marine engine (or climbing significant grades loaded up).

 

After much adjustment, including making my own throttle cable bracket adjustment piece and adjusting the length of my throttle cable, the best I could get was 96% TPS. 92.4 is probably ok. Not sure getting it up a little more would make much difference unless you are chasing every last HP.

 

That's interesting. I have always wondered if taking the time to make this type of timing curve would make much difference.

 

Dyno time would be great. In my case I am not looking for horsepower. I can make more horsepower than my 46 year old engine can stand. It is all about what is a safe reliable tune. So when it goes into boost it is going to be on the rich side and have very conservative timing.

 

Re: FI Tech "Go EFI 4" Self Tuning Throttle Body Injection Install Threa

I figured out a few things this week.

1. There are some very cool files on the handheld controller. Look in the folder FiTech PC Software.
2. You will find directions for installing and using the FiTech software.
On my Dell laptop the install did not work until I installed it with the WiFi connection turned off. Have no idea why.
3. I needed to make a folder called log_file for the data logging files. So if you do not see that in your handhelds directory the ECU won't know where to send the data log.
4. To look at the data in the FiTech app go to "chart" and select what you want in your chart.

 

I finally got time to do my fitech install only to find out that it doesn't fin with a stock intake...Sigh...
this thing just keeps getting more expensive. What other intakes will fit with the stock air cleaner?
Has anyone else figured out a way to make the stock intake work?
Any help is appreciated, i hate to have my car down for much longer

is this the edelbrock that will work?
http://www.jegs.com/webapp/wcs/stor...ltsPageCmd?Nrpp=20&Ntt=edelbrock+2146&Tab=SKU

 

The FiTech is setup with mounting holes in the base for a square bore or Dominator style intake manifold. The stock intake is setup for a spread bore (Q-Jet) bolt pattern only. Anything but another Q-jet would have been a no-go without an adaptor. Most of the adaptor plates are about an inch thick so your foam seals are gonna get squished. All of that said the open style spacer below should work well for your application and the price is hard to beat.

However the top of the FiTech throttle body does not have the appropriate locating notches for the stock air cleaner so a little dremel work is going to be needed on the Fitech or the air cleaner base. Real82it is using a GS air cleaner base so maybe he has a solution.

http://www.jegs.com/i/JEGS-Performance-Products/555/15440/10002/-1

 

Thanks Ken, the throttle linkage hitting the stock intake is the biggest problem. I guess maybe I should just buy an intake and shave a few pounds anyway.

 

I am running a GS air cleaner. I used a 1/8 inch air cleaner spacer and trimmed it to fit around the 2 tabs on the air cleaner itself. There are pics in this thread. Also, you can trim down your foam based on how high the adapter spacer is. I also previously did this to accommodate the edelbrock intake and nitrous plate. The added bonus......your foam will not get so worn out and distorted as quickly because there is less to compress. If you need more pics let me know and I will post. Hang in there....it is worth it in my opinion.

 

Linkage would STILL hit if you installed the .750in thick Jegs adaptor plate?

 

Great question, i will check that out today... Just when I had myself talked into the new intake hahaha.
Is the intake alone worth any performance gain? I have planned to add intake and heads some day.

 

What are the chances of getting some pictures of your throttle cable bracket? I can only get about 3/4 throttle out of it. I guess i need to do as you did and check TPS percentage also.

 

I'm using a throttle bracket from FAST and a JEGS throttle cable on mine. I'm not sure how well the factory cable would work.

 

Thanks for the pic Ken. If I can't make my stock cable work, I'll go that route for sure.

 

Ken, I do not get full throttle when I attach the throttle cable to that position on the throttle arm. Did you do some modifications to the gas pedal?

 

Here is what I did. I made an extension with a piece of steel that moves the bracket back appx 1 inch. Because I also have cruise on this car, the cruise bracket provides stability and does not allow it to rotate. I did this because my cable was binding on the housing. Moving it back allowed full travel.


In the passenger compartment I also took a 1 inch small metal round tube (not sure what it was.....but you could use a 1/8 brass nipple or something). I cut a slot in it so it would fit over the cable in front of the gas pedal. I then crimped it down onto the throttle cable. This causes my gas pedal to stick up higher and effectively gives me about 1 inch more pedal travel before it hits the floor.

Between the two changes, my TPS % went from the low 80s (if I recall correctly) up to 96%.