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Old 04-26-2016, 08:47 PM   #1  
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Default New 400 hp FiTech Fuel Injection vs carb

I'm considering going from my Edelbrock 625 (with Performer intake) to the new $795 standalone 400 hp FiTech Fuel Injection unit. Reason isn't that I have huge driveabliltiy problems with the carb, it drives fine, plus I've been a carb guy for 50 years, they are easy.

My problem is hot starts, most anytime after the initial start you have to spin things for many seconds due to fuel boiling in the float bowls, flooding the engine. Have the same thing with my 1970 340 Duster running a Carter AFB. Of course todays fuel is no help.

Things I've done to help the carb out is add a phnolic spacer, wrap the headers, route the fuel lines outside the frame rail away from the exhaust system and add hood vents to help cool the engine compartment. I'm sure this helped, but the problem did not go away. Oh, I also run only non-ethanol gas.

Now I see a 400 hp FiTech Fuel Injection system for $720 (after a $75 rebate) at Summit.

Anyone have any thoughts or comments?

Thanks, Ron
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Old 05-05-2016, 08:58 AM   #2  
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Hit the "confirm order" button on Summit yesterday. My net research indicates FiTech is dealing with more orders than they can meet in a timely manner.....The perhaps optimistic delivery date for the FiTech Go Street 400 hp unit is May 31st.

I also ordered a few -6AN fittings along with the fuel injection hose and appropriate clamps (not worm gear) I'll use at the tank.

The plan is to run a new 3/8ths nickel copper supply line on the drivers side and utilize the current 5/16th supply line for the return.

One detail I've found conflicting information on is the flowing pressure from the 1.6 Miata fuel pump, the quoted online pressures range from 50 to 90 psig. I went to considerable trouble to run the current (5/16) supply line away from the header, outside the frame rail on the passenger side. Due to tight clearance in one area hose was used to make a connection on two pieces and with the 4 psig for the carb it's a non issue, fuel injection return pressures being greater, this'll require a rework.

Now, come on FedEx!
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Old 08-11-2016, 11:01 AM   #3  
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Well, the 400 HP rated 30003 Fitech finally showed up the other day. I've been busy with life and just getting around to the installation. Have the new 3/8th supply line in place and the old supply line is now the return. Yesterday I replaced the stock fuel pump with a new stock replacement pump along with a new Wix fuel filter as "Just in case" move.

I "May" have a problem with the Summit AN-6 fittings I used on the Summit stainless PTFE hose. This is only used to transition from the hard line that goes under the car to the Fitech unit. I've started another thread for this issue and would appreciate your input.

I'll get back in the shop in the next couple of days and do the wiring and hopefully fire it up and see how it runs before the weekend is over.

Wish me luck!
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Old 08-15-2016, 07:18 AM   #4  
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It runs again! I finished up most of the final details yesterday, the primary ones being installing the oxygen sensor and installing the proper stainless/PTFE tubing ends on the underhood fuel lines.

1st start was quick, I turned the key on bringing the Fitech online and it turned the fuel pump on, you can hear the fuel pump shut off after a few seconds of pressurizing the system, then engaged the starter and it spun the engine over 5 or 6 times, and it started! After a few seconds of high idle it settled into a nice 700'ish rpm idle (factory default was 900, you adjust it to your liking with a iphone size controller that shows all the important information).

I let it run long enough for the Fitech to turn the fan on and it came on at exactly 195, shutting off at my set point of 185. I'll play with those setting some while finding the best set points for keeping things below 210 while in slow/stationary traffic. I'm running a 180 degree thermostat have no cooling issues while moving. One Fitech feature is it displays underhood air temps, it'll be interesting to see just how hot it does get in the engine compartment.

If the rain stays away I'll do a test drive today and let the self learning feature start the tuning that hopefully takes care of a few niggling issues; sometimes slow to return to full idle, has to turn over 5 or 6 times to start sometimes (which is still much better than the old 30 seconds with the carb on a warm engine).

OH, throttle response is GREAT.

Air cleaner; the 3/4" spacer and going to a shorter 2" air filter did work and the big 14" Edelbrock drop base air filter fit fine.

RR
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Old 04-08-2018, 07:50 PM   #5  
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Did it fit under the stock hood?
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Old 04-10-2018, 08:10 PM   #6  
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Did it fit under the stock hood?
Yes it did. It should be noted I'm running a stock unmodded oil pan and had already removed the hood brace over the air cleaner.
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Old 04-17-2018, 11:19 PM   #7  
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I just bought a dual plane intake, I did notice the 800 hp fitech was a little taller as installed it on a customer car. Did you get the factory tach to work with the Msd box? Or are you running an aftermarket tach? I really want the factory gauges to work on my 2002 Nb
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Old 04-18-2018, 09:37 AM   #8  
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Looking for opinions....

I have a 87 302 EFI system, really hate the look of the big upper intake.

Do you think this FiTech system would work as well or maybe even better than the stock system ?

TIA,
Devlin
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Old 04-18-2018, 09:44 AM   #9  
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Looking for opinions....

I have a 87 302 EFI system, really hate the look of the big upper intake.

Do you think this FiTech system would work as well or maybe even better than the stock system ?

TIA,
Devlin
fitech works much better than the factory ecu imo, with big cams it drives smooth with no bucking at low rpm. It self tunes. Controls electric fan and very easy clean wiring
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Old 04-30-2018, 01:02 AM   #10  
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I’m super happy to hear about your success with fitech! I’ve been planning on going the new efi system route too. Trying to decide between fitech and Holley sniper system.

Im also interested in your oil pan crossmember setup as you are running a stock truck pan. Did you go tubular? What exhaust headers?

Thanks for the post! It’s very encouraging as my 302 has AFR heads and a rather lopey cam.
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Old 05-01-2018, 02:30 PM   #11  
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This may be a silly question...

When replacing the stock EFI with this unit is the mustang computer eliminated along with its wiring harness ? Also, I assume there is no need for the Miata harness or computer either ?

My reason for wanting this system is looks and ease of installation.

Thanks in advance
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Old 05-01-2018, 03:50 PM   #12  
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This unit replaces a carburetor, so there is no stock EFI computer. Timing remains uncontrolled, with the distributor. If you already have EFI, I don't know why you would use this instead of just replacing the stock computer with a standalone (such as Megasquirt) or modify the stock computer with something like a Moates Quarterhorse. But I'll obviously let those with direct experience respond with why this would be a good alternative to factory (or standalone/piggyback) EFI.
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Old 05-01-2018, 08:13 PM   #13  
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This is a self tunning system. Not only does it looks clean, what I like is the way in manages a big cam and the drivability is better than what the mustang ecm can produce. You will eliminate all wiring harnesses and replace it with its own.
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Old 06-19-2018, 05:24 AM   #14  
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Currently running OEM EFI with Trick Flow Stg 2 cam and heads, and cannot get the thing to run right. Found a NIB FiTech 400 setup for half price, and snagged it because the price was so good. Pretty sure I am going to pull all of the old Ford stuff out and go the FiTech route, still researching. I know I need to get a new distributor/ignition and intake manifold, anything else? I figure I can just use the OEM Mazda fuel pump/lines, and adapt them to the FiTech.
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Old 06-19-2018, 09:07 AM   #15  
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You will love it. The stock fuel lines is the way I’m doing it. It will look muck cleaner. Summit sells a Low profile 2” tall filter with an offset flat base. You can’t use a drop base because they get in the way of the throttle linkage and fuel line fittings in rear. Be sure to carefully remove the modified harness and label. It’s worth good money here. You can technically wire the fitech directly to the fuel pump but I’m using a relay to avoid overloading it. You will also need a throttle bracket
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Old 06-19-2018, 09:11 AM   #16  
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Quote:
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I figure I can just use the OEM Mazda fuel pump/lines, and adapt them to the FiTech.
I would replace the fuel pump to a 190lph or 255lph
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Old 06-19-2018, 09:52 AM   #17  
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I would replace the fuel pump to a 190lph or 255lph
Is there a in tank replacement for the Mazda fuel pump that fits these parameters ?
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Old 06-19-2018, 10:00 AM   #18  
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Currently running OEM EFI with Trick Flow Stg 2 cam and heads, and cannot get the thing to run right. Found a NIB FiTech 400 setup for half price, and snagged it because the price was so good. Pretty sure I am going to pull all of the old Ford stuff out and go the FiTech route, still researching. I know I need to get a new distributor/ignition and intake manifold, anything else? I figure I can just use the OEM Mazda fuel pump/lines, and adapt them to the FiTech.
A couple relays for the fans(required) and fuel pump if desired, AN fittings to adapt the Mazda lines to the fitech. I went with some EMI shieiding for the blue tach trigger wire also. Replace the fitech temp sensor with the AC Delco version, fitech sensor is known to read low which effects its tuning ability.
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Old 06-19-2018, 02:36 PM   #19  
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What is the AC Delco temp sensor you are referring to? Do you have a part number by chance?
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Old 06-19-2018, 02:51 PM   #20  
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I would just clean the IAC valve and properly set the base idle instead of guessing and throwing money at it, but that is just me. LOL!!
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Old 06-19-2018, 06:46 PM   #21  
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I have set and reset and cleaned parts and replaced sensors to no avail. Pretty sure the cam is too much for the stock ECU to handle. The more I search, the more common it seems. I got the FiTech for dirt cheap, and I like the idea of newer tech vs 80s tech. Also better hood clearance and less weight vs that heavy EFI manifold. Still researching, but pretty sure i’ll be swapping. I very well may just get a milder cam and stick with the Ford EFI as well, not sure yet.

R2564952, is summit part SUM 239422 the offset filter you are talking about?

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Old 06-20-2018, 03:48 PM   #22  
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What is the AC Delco temp sensor you are referring to? Do you have a part number by chance?
AC Delco # 213-928
GM #15326386
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Old 06-21-2018, 05:26 PM   #23  
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My FiTech 400hp kit showed up today. Can't believe how cheap I got it new in box. Still researching options, not 100% sure I'll yank out the factory FI, but I definitely like the simplicity of this unit. Will clean up the engine bay, that's for sure.
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Old 06-23-2018, 07:04 AM   #24  
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This thread makes me want a Henry Ford V8 with new technology, classic looks, and one of the best sounding mass-produced V8’s in the land!
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Old 06-24-2018, 12:20 AM   #25  
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R2564952, is summit part SUM 239422 the offset filter you are talking about?
Yes, that’s the one I’ll be using
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