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Discussion Starter #1
I bought my wife a '67 LeMans convertible. The poor original OHC6 puked & burnt more oil than I could keep in. 2 months after buying the car, it now has a new XU 1967 400 motor w/ 061 heads. Everything stock with exception to the Melling SPC-7 cam & Comp Cam Roller tip rockers. The car ran decent with a new Edelbrock 600 carb but it needed more, even after changing things around with a new calibration kit.

That's when I decided to give a Fitech 600 a try with the rear mounted electric pump. With the wife driving it, I figured the fuel injection would be maintenance-free, no-carb-problem upgrade.

My first impression was the AMAZING throttle response it had, not to mention it burned efficient (no heavy exhaust smell). I decided to run down and fill the tank for a test drive. As I'm pumping fuel, a crowd congregates around checking the car out. After some chit chat, I hop in and attempt to start the car. It tries...and tries...and tries.... I make some adjustments on the hand held controller...nothing. Long story short: I sat at least 30 minutes before the car would start and sadly this would continue ALL summer long. Many hours on hold with FiTech and no real resolution. The car will start but it takes at least 3 attempts and you have to feather the gas to do it (kinda defeats the purpose of fuel injection). Quite embarrassing when you're at a car show or have a crowd gathering around at a gas station.

I've reprogrammed at least 6 times, made hundreds of adjustments (as advised by FiTech), added more grounding straps, wrapped the system wires in 3M shielding tape (to prevent any possible electrical interference issues), checked/rechecked/double rechecked timing (all good), checked vacuum (a bit low at round 7-8 at idle) but I've never owned a Pontiac with high vacuum before (my '65 runs @ about 6-8 on idle). I'm at wits end!

Anyone else make the plunge with the FiTech system and have had success/ problems/ issues?
 

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No experience with that system but does is require a certain fuel pressure for startup? On EFI vehicles I've owned that developed startup problems, low (or no) fuel pressure was usually the cause.
 

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Discussion Starter #3
I was contemplating installing a fuel pressure gauge to see if I was getting the correct pressures (I believe 58 psi).
 

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That would be the operating pressure but does that system require a certain amount of pressure to be held for startup or does it do a instant prime when the key is turned on?
 

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Discussion Starter #5
"That would be the operating pressure but does that system require a certain amount of pressure to be held for startup or does it do a instant prime when the key is turned on?"

It requires 58 psi of pressure. When you turn the key, the pump engages for about 2 seconds and clicks off...line pressurized...ready to start (I assume the internal fuel regulator has the sufficient pressure and shuts the pump down momentarily until it starts). You can change the initial prime by increasing the amount on the handheld. The only problem is that I've done this over and over. My hard start issues are strange because after 3,4 or 5 failed attempts to start the car...I adjust just one random, insignificant number on the handheld and it will typically fire up (with the help of feathering the pedal). It sucks to start but great when it runs...
Really frustrating.
 

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A pressure gauge would be a good idea. I'd be curious to know what the fuel pressure is in those two seconds before startup. Is that adjustable?
 

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Discussion Starter #7
A pressure gauge would be a good idea. I'd be curious to know what the fuel pressure is in those two seconds before startup. Is that adjustable?
I don't believe it is adjustable. I will try the pressure gauge...it can't hurt. Thank you!
 

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There are a bunch of guys on the Corvette forum who've dabbled with add-on fuel injection, and I would say that 80-90% of them ended up taking it back off due to performance and reliability issues, along with poor product support. All of them spent a ton of $$$ and time. My advice is to yank it and install a stock intake with a quadrajet carb, or bolt on a tripower set up. These units are more reliable than aftermarket fuel injection if set up properly in the first place. I have a '67 GTO convertible with 250,000 miles on the clock, with its original Q-jet carb and points distributor. Stone reliable for the past 35 years I've driven it, with the last carb overhaul about 25 years back. Young women can drive carbureted cars---they just need to be educated. If they're my age, they learned to drive on carbureted cars, and calling them young would probably be a bit of a stretch!
 

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Oh that poor Lemans. OHC 6 CLINIC IS WAITING

:crying:We've seen this way to many times after attempts "to make more power"
Ask anyone who has transplanted an OHC 6 for a run of the mill V8,
Your Lemans is likely suffering from Transplant Rejection.
Luckily you didn't go with an LS transplant or your Lemans would likely be dead.

The good news is there is hope but time is of the essence, you may be able to save her with another OHC.
ACT FAST the clock is ticking...

Pictured below is an OHC on Life Support waiting to be re-installed.:wink3:

Sorry couldn't resist, I feel your pain but always sad to see another Cammer sacrifice :|
 

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Discussion Starter #10
Geeteeoh...i am a patient person but last summer sucked, as far as cruising. I have never had carb issues and my 65 tripower has never failed me. My problem to overcome is my investment $$$ in this system. I'm stubborn or at least that's what my wife tells me. Some guys have zero problems but I'm hearing more bad than good now that Fitech has been on the market for awhile. I will give it one last go but I'll have a carb ready to go...just in case.
 

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Discussion Starter #11
Gtojunior, i didn't have a problem with the inline but it was a dog, burned oil and Exxon Valdez'd the garage floor. I just happened to have a spare 400 sitting there. Now, if i shoe-horned a Chevrolet engine in there....let the beating begin. Lol
 

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lil65, it sounds like you have plan B worked out and you'll come out of this ok. I love challenges myself, to a point. Everybody is different and has their own turn-around point. Hope the FI works out for you, and if it doesn't, you'll be cruising it carbureted......no biggie.
 

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I spent a lot of time last summer getting the FiTech system to work right on my '70. Some of the things I learned was that the pump and primary filter must be mounted below the tank. I went through three pumps (on my 3rd now), but traced the problem down to sediment in the old tank, and replaced the tank and sender/pickup, which was no fault of the FITech. The problem was finally found by using a pressure gauge which would show pressure dropping to zero, the motor running like crap. The system also needs a long time to learn, not a few minutes but closer to days. There's a couple of posts here the mention the prime shot, and that is indeed adjustable. The factory setting is 4 seconds, which I felt was too long for my application, so I dropped it to two seconds. Over this winter I went ahead and changed all the settings for a 0 degree startup, and was surprised to find that it fired right up in 30 degrees temp, idling perfectly. I'm not known for my patience but will say that if you stick with the FiTech and work out the glitches, you'll be happy with the results.
 

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I put this on my 70 judge last summer but I used the command center for fuel. Loved the way it ran and lack of exhaust smell, but I also have starting issues. Tried many settings, extra grounding, and factory software updates with inconsistent results. More than likely will pull off in the spring. The chevy boys on the chevelle forum seem to have better luck than we do with this system. It was designed for a 350 but factory Said a Pontiac 400 is not an issue.
 

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Try decreasing the cranking fuel to lean out the cranking AFR at the warmer temps on the controller.

When you crack the throttle with your foot you are letting more air into the engine to try to fire it off. The crank setting is fixed and doesn’t look at the throttle position while cranking. Because of this you are leaning out the cranking AFR on the engine. By decreasing the amount of cranking fuel you can also lean out the cranking AFR on the engine.
 

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Just was reading your post I realize its old but I installed one on my 70 Nova BBC 438 number 3 cam profile and love it had no real issue except that I did clean all the line after cutting them by the way they are the braided steal rubber lines high pressure. there must of been some junk in the line tubing because the 30 micron filer got plugged so my pressure prior to the filter went up to about 99 PSIG so the car would start but you couldn't push on the gas with out it bogging. installed new filter and it worked fine. absolutely love it in fact I'm putting on my jet boat this summer. Hopefully you found the problem.
 

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FYI
I went with the Holley Sniper last summer. Very similar to the Fitech unit.
Took a bit of adjusting.....but it’s crazy good now.
I just went out to fire up my ‘69 400 for the first time in 4 months.
Didn’t even get in the car....just reached in and turned the key to on....about 3 seconds to let the pump cycle.
It fired up and idled perfectly.

Didn’t start out this way. I used some really bad words a couple times getting it right. But now very happy and amazed at how great it is to cruise. My biggest complaint is literally the throttle is too sensitive....touch the gas and it goes.
 

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Fitech Tri power fuel injection

Hi.

I tried searching to see if anyone has completed a Fitech tri power fuel injection on their GTO and couldn't find anything. I have a 65 GTO with a 1975 Pontiac 400 with 670 heads and the thought of tri power fuel injection is very appealing. I'd appreciate any responses from those who've done it and knowing the issues they ran into doing the conversion.

Thanks!
 

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Fi tech and Snipers are like the old throttle body injection, two injectors delivering the fuel thru the center of the intake.

The cylinders don’t know if you have FI or a carb, what they respond to is the correct Air Fuel Ratio..AFR

So if the AFRis right on the idle circuit, which is up to about 2500 RPM’s...on the primary circuit above 2500 Rpm,...and on the secondaries when vacumn Venturi speed is high, pedal mostly down.....and with the accelerator pump and power valve circuits all delivering the right AFR...

A carb can do it,...FI can do it....

I use a Quik fuel carb, a vacumn gauge in the cockpit and a wide and 02 sensor in each exhaust with a gauge on the dash...

First I tune in the idle circuit, with the mixture screws and the idle air bleed jets on the top of the carb, with a quick fuel all you need is a screwdriver.....

Next I see what the primary jets are doing, drive at speed above 2500, read the AFR and vac gauge....if too lean or rich return to garage and change main jets....

Same with secondaries, power valve and accelerator pump......you can dial them all in,...not while driving and not with a computer, but with your jet changes on the carb when you return....

Your car can run just as good as any fuel injected car....it is the AFR that must be right not how you achieve the AFR....

Now a multi port FI system has more advantages because it delivers an exact feed of fuel to individual cylinders....

But the throttle body ones and similar to carbs,.....and one of the easiest to dial in every circuit is the quick Fuel......

So lots of ways to achieve a good running engine:nerd:
 
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