FiTech Fuel injection
 

Hello all,
I'm thinking really hard about running the FiTech fuel injection system on my '68 GMC with a '69 427 that's been bored out to 433" (+0.030" over). It's got a Skat forged crank, Forged rods and Icon forged pistons, running 10.5:1 compression with 105.9cc rectangular port heads. It's got an Edlebrock RPM Air-Gap intake & HEI distributor. Since this engine could see over 600 HP, likely with a different cam, I was leaning towards the FiTech MeanStreet system that's rated up to 800HP. I like that the 600 HP system can adjust timing, but don't want my fuel injection system to be the limiting factor on my power. I live at 6,800 ASL and would like to freely drive the truck down to lower elevations without constantly tuning the carb. So, that's why I've been looking so hard at these systems.

Does anyone run one or have experience with them? They seem pretty slick. Just want to ask before dropping $1,500 on the MeanStreet with the fuel management system.

Thanks for any input!

Nik

Re: FiTech Fuel injection
 

I use fitech fuel injection on my 72 blazer and it works pretty good but there are a few little bugs that are difficult to get rid of if you don't know what you're doing.. (like me) I've had the go EFI 400 hp with fuel command center for nearly 6 months and I still have a little bit of hesitation (but I'm figuring it out) when giving it gas while coasting, and the fuel pump was overheating but I solved that problem by removing the float and running a fuel return back to my tank. But it performs a lot better on cornering offroading and drivability overall. But their customer service is pretty much garbage everything I learn about the unit is from a group of very smart owners on Facebook who try really hard to help.

Have you looked at holly sniper EFI? That something I wish I would've waited a bit longer for, but I don't regret buying the fitech it's just a little fickle at times
If you have any other questions I can try to answer them

Re: FiTech Fuel injection
 

The Holley Sniper kit was the other one that I was really interested in! That's too bad to hear about the FiTech customer service! A company like that needs to have incredible customer service.

Re: FiTech Fuel injection
 

Yeah it's a bummer there used to be some fitech employees in the fitech owners group but they left when some members got mad at em for lying about a mean street edelbrock intake package deal, when customers received their orders they were no name Chinese intake manifolds instead of the advertised edelbrocks. And fitech refused to answer questions about them and wouldn't do any compensation. I'm sure with the Holley there could still issues with tuning but I feel like you'll get better customer service from a Company that's been around for as long as they have

Re: FiTech Fuel injection
 

From what I hear all of fitechs offerings are made in China which keeps cost down. Now this alone is probably not a big runoff for most, but I believe its the reason for their prices being low so quality may be limited. This is all hearsay so I would research before taking my word. I would suggest Holley as I have always heard good things but from what I've heard the sniper kit is really an entry level kit so it may not fit your needs. A call to Holley can answer some questions on what you should get. Consider buying it from summit racing. They have a 90 day return policy and are really good about standing behind your purchase if you have issues.

Re: FiTech Fuel injection
 

Also I've been seeing atomic EFI dropping in price to try and compete with the new units, I saw one for sale for $999 which is only a 100 or 2 more than the Fitech. and it's been around for a while now so there shouldn't be t many bugs?

Re: FiTech Fuel injection
 

Aftermarket EFI systems have no altitude compensation. A well adjusted carb is actually less problematic.

Re: FiTech Fuel injection
 

Actually that's not true. They measure O2 reading (wide band O2 sensor) and as you go up or down in altitude, the available O2 will change. The EFI will compensate based on the A/F ratio. These newer EFI units learn unlike the older EFI units that just use a specific fuel table only.

There have been many reports of people with these newer EFI having great success with altitude issues, going in 5000-6000 ft elevation changes and the vehicle runs great and starts easy. Almost all of them said the same thing, they could never get their carbs to make that big of a swing and run correctly.

Re: FiTech Fuel injection
 

So, this is completely opposite of what I've read and understood about these systems! That is the one on only reason that I was considering running something like the self learning FiTech or Holley Sniper. My understanding is that they continually take readings from the wide band O2 sensor (s) and adjust to the optimal air:fuel ratio based on the information that they get from the O2 sensor. The air density changes as elevation changes, therefore, they are continually adjusting for altitude based on altitude air density changes. I'm trying to learn as much as I can about these systems. So, can you explain how they do not adjust for altitude?

Thanks,
Nik

Re: FiTech Fuel injection
 

I'm sorry, I should have explained myself. There is no specific "altitude compensation" because an engines volumetric efficiency (as in the ratio of received air charge volume to cylinder volume) doesn't change with altitude. There are other factors however that will impact actual mass airflow, the greatest are air pressure and temperature. An EFI system that uses the before mentioned fuel-table map would actually work the best IF all cells in the table are accurately mapped. That means very intensive tuning. Here's where the wide-band oxygen sensor comes into play, it can somewhat compensate for this by using real time data, but your automatic fuel-curve correction is always more or less playing catch-up which can be very problematic in a racing or performance application. So, long story short, if you are not racing in the mountains you should be ok. So, technically, not a true altitude compensation, an O2-sensor compensates for changes in pressure and temperature which will keep your engine running well but not as well as it could run with specific tuning.

Re: FiTech Fuel injection
 

Do these systems not have a map sensor?

I don't know these systems but I would assume, like the OEMs, the computer takes a baro reading at start up and updates it everytime the vacuum goes to zero (WOT)

Re: FiTech Fuel injection
 

You are correct, Bigdav, some systems do use a Manifold Absolute Pressure (MAP) sensor, while others use a Mass Air Flow (MAF) sensor. While a MAF sensor meters the amount of air going into the engine, a MAP is basically just a pressure meter. MAF sensors systems are
more accurate. A MAP sensor can not read density, which changes with temperature, so an additional temp sensor is necessary. EFI systems using MAF make tuning adjustments in open loop operation based on the input it receives and at WOT goes into closed loop operation. MAP systems on the other hand determine it's air/fuel-ratio and ignition curves on preconceived maps. Rather than tuning in open loop it takes it's sensor signals and select a pre-programmed map. That's also the reason why MAP systems cannot compensate for a power-adder, like a blower, while MAF systems can compensate even for aggressive power-adders.
The wide-band O2 meters the amount of O2 in the exhaust gas which helps to adjust A/F-ratio.

Re: FiTech Fuel injection
 

It's a real good option for the money. If the engine has 12 in or more vac it runs real good. Even the cars that I couldn't make absolutely perfect every customer was still very happy. If they would just give a little more fine tuning I could make it 100%. There are systems like that they just cost more and need total custom tuning. Different options for different people.

Re: FiTech Fuel injection
 

I've had zero problems with mine for close to 2 years.
Now I'm reading up on letting it control my timing.
I found a lot more help here:
http://www.chevelles.com/forums/89-efi/

Re: FiTech Fuel injection
 

Wow. Very informative! Thank you for your response. So, have you done research on any of the systems like the Fitech, Holly Sniper (or Super Sniper), FAST, etc? I live in the mountains and want to be able to drive my truck down to sea level. My 1406 Edelbrock works very well and the truck always starts easy. I have it jetted a little rich, to give myself the ability to safely take it down the hill, but hate it always running rich. Just trying to weigh options.

Thanks for all of the inpit!

Nik

Re: FiTech Fuel injection
 

The Sniper can compensate for altitude, it has a map sensor and iat sensor both. I believe Fitech does too but I'm not sure. I was looking at both but the Sniper has more features so I went with it. I'm very happy with it, I have probably 1500 miles on it now. I did have some trouble when I added timing control but I believe it was caused by my wiring and how I routed it. I'm redoing that now and going to try it again.

If you decide on a Sniper I recommend purchasing through www.efisystempro.com they offer their own Holley trained tech support and have been extremely helpful and easy to get ahold of.

Re: FiTech Fuel injection
 

Cool! So, I haven't looked into it much yet, but I've recently seen that Holley has the Super Sniper now, not just the Sniper. Surely it has some extra features? I'll read up on it today. I'm leaning towards the Holley system myself.

Re: FiTech Fuel injection
 

Running the MSD Atomic here ( with full kit system including return line to tank ). Runs like a champ! If this system is now priced below 1000 as was reported in this thread, that's a huge discount over the original pricing of over 2000!

-klb

Re: FiTech Fuel injection
 

Nikwho,
I've been helping my buddy get his fitech running good for over 6 months. It's still not great, just ok. I just finished a sniper on my Vortec 350 and it runs very good right out of the box. I did a LOT of research before choosing the Holley over FiTech. One of the main reasons is the excellent customer service (tech line) but more importantly the forums that is hosted on Holleys website. There is a sniper specific community that is a wealth of help and information.

Re: FiTech Fuel injection
 

I commented here almost a year ago I feel like I should give an update since this thread revived. I got rid of the fi-tech system altogether because it kept pissing me off to no end. It always had a little stumble on acceleration that I couldn’t get rid of, but then a couple months ago it started acting like it had a vacuum leak.. idling 1500 rpm horrible power loss and crap fuel economy. No matter who you ask they all blamed it on the newly built engine. I didn’t buy it so I sold the fitech and bought a holley truck Avenger carb and my blazer is running great now. If you’re going to go fuel injection I would go with the holley sniper for sure

Re: FiTech Fuel injection
 

I just installed a Holley Sniper EFI on my 72 blazer, it works really great. I am using my stock HEI dizzy and it runs better than the holley carb I had on it... The install is so simple and easy, turn the key to on position, wait a couple seconds, fires right up....no need to pump the accel or worry about the choke working correctly....I plan on putting this same system on my 72 c10 as well....

Re: FiTech Fuel injection
 

The Super Sniper is more for boosted or high horse power engines. If your not going over the regular Snipers limit of 650hp I dont think you'll need a Super level one. The regular one has a ton of features and I believe they are mostly the same with the exception of boost control.

Re: FiTech Fuel injection
 

Interesting. I do run nitrous periodically in my '68, but my timing is controlled by my Digital-6AL ignition box. I liked the progressive nitrous control feature, but, I'm actually now leaning towards continuing to run my Quick Fuel 850 Q series in that truck and looking now to run the EFI on my '59, with a 383 and a relatively mild hydraulic roller cam. So, it would seem that the standard Sniper would suit my needs well. Still mulling this over, but getting close to pulling the trigger. I've talked to a few people that aren't happy, or at least not particularly impressed with their FiTech systems. I'd like to hear more about how people feel about their Holley Sniper EFI before spending that much money.

Nik

Re: FiTech Fuel injection
 

I've been running the holley sniper on a BBC in a c30 for a little while now. Don't have enough miles to really talk about how it drives, probably only 250 miles maybe, but I'm happy with it. runs really good and seems to just run better every time we have it out.

Re: FiTech Fuel injection
 

:burnout:That sounds pretty nice!