Hey all,



I have a Summit Racing branded Fi-Tech



https://www.summitracing.com/parts/sum-240505



It works very well. The only thing that bothers me is the cold (and hot) starts.



You should be able to get in the car, turn the key, and go.



The way it is now, when cold, you need to “spritz” twice. For hot starts, spritzing once is enough. THEN you crank and it starts perfectly fine.



By spritzing twice, I mean you need to turn key to the on position. Wait three seconds as the fuel pump turns on and then fires a shot in the throttle body then shuts off.



For a hot start, you can then crank and start. For a cold start, you have to repeat the process a second time: turn the key off and back to run, spritz a second time, then crank.



According to the instructions, you should be able to crank and go. The instructions give no explanation on steps to take if that is not working.



Any thoughts?



I guess I should increase or decrease the priming shot.

 

This seems odd to me. I have an MSD Atomic system and it's crank and go every time. Did it come with a tuning guide? Does it have an idle air circuit and throttle blade setting? There is a relationship there for my system, not sure about yours.

 

Does it actually squirt a shot of fuel into the intake when the key is turned on? And this process takes 3 seconds? I have to say, never heard of that one before, it sounds like a cheesy starting patch because they couldn't get the cranking start right. You should be able to turn the key and crank it and it'll start right up.

Anyways, if you can adjust that priming shot then I suppose that'd be the way to fix it. There should be a table for the start something like fuel vs coolant temp that lets you pick how much extra crank fuel to add.

 

Apparently it does both.

if you set the key to on, the pump starts and it fires a spritz after 2-3 seconds.

if you immediately crank, it immediately pressurizes and spritzes simultaneously.

 

The question is what to change…. Is there a cranking shot and does it need to be richer or leaner. I read something somewhere that it is overly rich.

 

I am not aware of this as a setting with my setup.

I did however notice that the speed the engine fires was different before I connected the computer to the distributor. When the ignition was stand alone it fired immediately. Once the ignition was connected with the hall effect sensor the system let's the engine tune over a couple times before it fires. I am assuming this is for the computer to verify the timing before she lights the candles.

 

I am running the Summit MAX500. most likely the same system you are running. Instructions suck.
Yes there are settings for cranking fuel. and warm up fuel. etc. The are A LOT of settings they don't tell you about. To get it to idle down quicker, acerater pump settings, And on and on. Just having my morning coffee. But if I know more about your engine I can walk you through it all.
Auto or manual? Cam? compression, idle vacuum?

 

I have an actual FiTech system and it does not do this. When you turn the key on, it primes the fuel pump and gets it up to pressure, but the injectors do not fire until you start to crank - and mine starts right up. Are you sure FiTech makes that Summit setup? It looks nothing like any of the FiTech gear I have seen.

 

Hello Dorian,

I have a Holley Stealth Sniper EFI system on my 427 now. When you start my car it is the same as with my C4, you turn the key and "wait" for the fuel system to prime and squirt a startup fuel shot and then you crank the engine. It takes only a short time 2-3 seconds and but can be a nuisance sometimes when you are in a big hurry and still while getting used to it. When my engine is warm it starts right away. The tighter the fuel system the less time it spends priming. The company I bought my system from gives unbelievable "Post-Sale support. They just emailed us an article that helps explain how to set up a cold start system on the Holley system easy winter driving. It is can be done in the software that Holley gives you with the Purchase. My fuel system holds 58 to 60 p.s.i. for 1-3 weeks so there is no issues with waiting for fuel. With the electric fuel pump inside the fuel tank on my C3 is wonderful, no noise or hum or anything.

I don't think it is anything bad to do this as GM made the C4 Corvettes the same way. Insert key and rotate one notch and wait for pump prime and then crank. Does the FITech system have a way to control the cold start on a temperature curve? This is the latest article I received from the guys who sold me the equipment. It is not about the FITech system but it might help you understand where and what to adjust on your system. It should be similar I would think.

The author writes well and is fairly clear, check it out:
https://www.efisystempro.com/efi-pro...eid=bd39f11d48

I hope that the FITech system can learn how much fuel it needs at specific temperatures. If you don't want to wait you can go into the software and make a couple adjustments and you should be going.

It sounds like our friend 4-vettes has just the kind of experience you need to help you out with that specific system. I hope you get it working in the cold really well!

I wish you all a Happy New Year!

 

Fi Tech definitely makes the Summit system. A lot of it is the same, some different. It was Fitech that finally sent me the tuning software because of the issues I was having. And I was able to talk them into it after months of talking to idiots only because I am a dyno tuner by profession.
Seriously, I can walk him through this. I just need some info. from him, and the time to take some step by step photos.
The summit system does have cranking fuel and warm up fuel adjustments. they just won't tell the end user ****.

 

Thanks gents for all the feedback.

The animal is a 400 SBC. 10:1 compression. Performer RPM heads and intake. Idle vacuum is 18 inches. The cam is a retrofit hydraulic roller by compcams

https://www.summitracing.com/parts/cca-12-422-8

it’s a manual.

 

it doesn’t have much in the way of a tuning guide but yes, you have to set the throttle blade position when hot. And it does have an IAC.

 

The product looks very similar to this

https://www.summitracing.com/parts/fif-30021#overview

The instructions seem identical. The only difference I could see is that the summit one claims to be limited to 500 HP where as the Fi-tech pegs it at 550

 

I'm happy to walk you through all of this. There are a LOT of settings that you may not be aware of. But this system is tunable. I've been running it for over 2 years. And although I have tuned with numerous systems. This one is different in many ways from all the others I have used. So step one is to ignore advice from anyone using a different system/tuner.
Step 2, understand the limitations of this system. In many ways it will improve your overall drivability over a carb. But it is NOT a modern sequential port injection system that sprays fuel right on top of the intake valve just as that valve starts to open. What it is, is a form of constant spray fuel injection. As such, the injectors are mounted on top of the intake manifold and constantly spray fuel. When the intake valve is closed, Fuel in that particular runner of the intake manifold is "Stored". Duel plane manifolds have the downside of storing more fuel in the longer runners and less in the short runners, causing tuning headaches for some.
So, bottom line with start ups. when you restart your warm engine. fuel is still laying in the intake manifold and start up is instant.
Now, cold start. there are different cold starts. one, you shut down just last night, restarting in the morning. Very likely that some fuel is still laying in the intake. This you should be able to adjust to start with in 5 seconds or so of cranking. And I can show you how.
now if the car has sat for a week or more. The intake manifold will be dry. Do Not consider it unusual for it to take 15 seconds, give or take for it to start under these conditions. But it should then fire and idle straight away.
I have mine so I can start it and back out of the garage straight away. I do not know of any way to post photos to a PM on this forum, So I will post it here. give me a little time to put this together.

 

O.K. setting fuel start up for dummies. Keep in mind my engine makes about 12 inches of vacuum idling at 800 RPM. Mine is also a manual, And as such I found a number of other things that needed adjustment as well. Seems it comes out of the box set up much more so for an Automatic car.
First big tip on a manual car. The IAC park position on this system is not adjustable. And is a multiplier of the last idle IAC position. Soooo, It can come in way to high when you let off the throttle. I can teach you some tricks to get around this if it becomes a problem for you. But step one is getting the IAC as low as possible. The instructions tell you to get it set warm at idle between 1 - 10. I would advise you to set it between 1 - 3. no higher. get the car to running temp, but before your fans kick in, if your running electric fans. get it set as low as you can. This won't affect start up as there is a start up IAC adjustment. it will greatly affect drivability.
O.K. first problem, cold start.
First, here's my set-up.

Okay, let's plug in our screen.
Should open like this.

Then in a few seconds should automatically go to this.

Now toggle down to number 3 Tuning.
Then hit enter. And it will open to this screen.

I have already toggled down to crank and warm up.
then once again, hit enter.

Now these are my settings. yours will likely be different. Now as you can see on the screen there are 2 different start fuel settings. Prime fuel is basically that first shot of fuel and the crank fuel is the adder that will continue to add start fuel until the engine fires.
in the above photo I have the Prime fuel highlighted, press the edit button on the bottom of the screen.

Now you can change the initial fuel squirt. Bigger number, more fuel. But keep in mind that you also need to balance cranking fuel with this. Once you change the number hit OK.
it will then pop back to the original screen. At this point you MUST save to ECU. every single change must be followed by saving to ECU. if you make a number of changes and then hit save to ECU, only the last thing you did will be changed.

You must see this after each change.
Now let's go back

Look at my crank fuel when cold . I have a bit of extra fuel going in when dead cold to help with cold start and maybe a bit to help with the dry intake from sitting for a week, but not so much as to flood it if it only sat overnight. Now cranking at 65 degrees. I have none extra fuel for cranking as it's just not needed on a warm day. and I have taken out fuel on a hot start as the prime fuel is actually a bit much when hot, but needed when cold. As you can see, it's a balance.
You can try my numbers if you wish. might get you closer at least. I put these into another forum members car here in Australia. He is running a 383 with similar vacuum as yours as has told me it's starting and running well.
Other than that it is trial and error.
Now, if it starts but dies, or just isn't idling well. the next adjustment is the warm up fuel.
After making changes, do not start engine. First, turn the key to off and wait 30 seconds. this will actually save the changes in the ECU. This is important. simply sending to ECU doesn't save into ECU. I know, dumb. but it's important. After making changes, turn key to off. wait. 30 seconds. then turn back on and start.

 

Your advice is great to get this system setup right, but wow does it really take 15 seconds of cranking to start it when it's sat for a week? I didn't know these systems were still that far behind on cold starts. I use GM stuff and it can sit all winter and start within 2-3 seconds of cranking.

 

In answer to above, yes. as I explained, if you add enough fuel for dead dry start ups, you'll be flooding it when it only sat for 6 hours.

 

Now, to set warm up fuel, Oh, And please keep in mind I live in tropical Queensland. it never gets below about 45F in the coldest part of winter, so my 20 degree settings are anything but accurate. I would imagine that if I lived in a colder climate I would have larger numbers in the 20 degree columns.
First one to look at for both start and warm up is this IAC setting.

The crank IAC is the park position of the IAC while starting.
it controls how much air your getting at start up.
You want to get your large gauges set up before starting the engine so you can see where your IAC is idling at upon start up. this park should be slightly higher than the IAC reading just after the engine starts. if not set correctly, all other settings will be affected and it likely will start and die or start and rev. then come back down. a slight rev on start up is better than dying.
So go to the large gauges screen.

hit enter


Pushing the toggle on the right up and down will scroll up and down the list. pushing the toggle to the right will select the gauge. to the left cancel it. there are a lot of things you can view. here I have selected AFR, Engine temp and RPM. You can also select IAC. which you will want to do when setting your initial IAC setting we talked about earlier. and now to watch the IAC right after start up. Do this with a cold engine. You can select up to 4 things on large gauges. if you only need 1. you will get a full screen gauge. once selected, press "show".

Once set up. start engine and watch your IAC just as you car settles in. What is this dead cold idle IAC reading? If it's 85. Set your park around 92 give or take.
Then you can get into warm up fuel

After start fuel only runs a few seconds and can be adjusted in pro tuning if necessary. Most likely you won't need to play with that, your engine with that much vacuum shouldn't need such fine tuning, Well, I would think. As you can see I don't have a lot in at 20 degrees, but I have some. the computer will split the difference between the 20 degree setting and the 65 degree setting if its say 45 degrees. None the less, hard for me to set this when its rarely below 70 degrees here. This is just fuel for the first couple seconds. then you have warm up fuel. This is sorta like your choke coming off. I am thinking of reducing the amount in my 65 degree setting as I am thinking I don't need this much. this will add fuel right up to a warm engine and will fade off as the engine approaches the warm temp. about 150 degrees if my memory is correct.
A fair bit of trial and error is required to get these settings perfect. I know they tell you these systems learn. But all they really learn is the AFR map on a warmed up engine. And then they learn to what they are told. How quickly they drop back to idle can be set. But they never learn this. how quickly the fuel snaps back on after decel can be set, but not learnt.
Lots of things can be set. The factory settings are set up on the safe side and for what they think is the average engine.

 

I stand corrected, the controller menus look the same as mine. I'll pull up my tune when I get home to compare.

 

Here is my current setup, and I have no cold start issues: