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I wish there was an easy way to put the carb on it for now.... but in-tank pump has way too much pressure

Add a return line and a fuel regulator. What pressure is required? I'd have theh same problem when I (finally) get the Weber Carbs on top. The old school solution - return line and regulator. The Webers have to be down to 4 psi. Well under an in-tank pump.

Just a quick thought - but may involve a bit of effort - and get you running.

Best of luck - the carbs would "bypas" the EFI problems. Suppose you'd leave the injectors in place?

Cheers - Jim

the injectors are inside the throttle body.... and on their way to California.

My biggest concern is whether or not I can get the pressure low enough not to lift the needle off the seat in the carb.... the pump, iirc, is 60 psi .... even with a bypass regulator, I'm not sure it would work.
 
along those same lines......can you kill the electrics to the in line fuel pump run an external cube pump connected to the lines and still draw gas from the inline pump?

yes, the problem is plumbing it.... it's hard lined all the way to the tank (minus 6")

still, this might be the solution.... need to talk to FiTech today about timing.... if they get something back to me quickly, then there should be no issue.
 
Looks like you and I are in the same boat.

My rant. These companies have been making EFI units for going on 20 years. And they still have not figured out how to replace a carburetor? That a massive fail! It's not that difficult. Evidence of this is that they made mechanical carburetors that seemed to work really well for almost 100 years.

I am no expert on software control but I have been involved in product development programs for more sophisticated control systems than EFI.

OK, I'm done. Rant over.
 
Looks like you and I are in the same boat.

My rant. These companies have been making EFI units for going on 20 years. And they still have not figured out how to replace a carburetor? That a massive fail! It's not that difficult. Evidence of this is that they made mechanical carburetors that seemed to work really well for almost 100 years.

I am no expert on software control but I have been involved in product development programs for more sophisticated control systems than EFI.

OK, I'm done. Rant over.

tube stereos still sound better then anything mimic'd by a computer. Therein, I think, lies the biggest rub of all.... all the technology and all of the innovation and we're still not better at nature then nature. It's so fun to listen to technologists go on and on about how great the innovation but it pales in comparison to what already is.
 
I think my only choice on the car now is either run what I got or replace it with a carb... nothing is available before late June, which is too late to test and tune before driving 800 miles.

And it doesn't seem FiTech is in any hurry either - so the only, realistic choice is probably a carb....
 
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I think my only choice on the car now is either run what I got or replace it with a carb... nothing is available before late June, which is too late to test and tune before driving 800 miles.

And it doesn't seem FiTech is in any hurry either - so the only, realistic choice is probably a carb....

I've got a spare Holley 950HP Ultra that I never used, if you need it. It's been sitting a while, but it has never had gas in it. I also have an unused Barry Grant HP fuel pump (BBC block mount). Barry Grant went out of business a few years ago due to personal legal problems IIRC, but he made great high performance fuel system parts.
 
A big enough bypass regulator will work. The return needs to be big so there is no (minimal)extra pressure drop.
 
I’m using a fuel injection pump and the bypass regulator is set for a carb.

You have to do this for a boosted application with the regulator boost reference, then you always have the right delta pressure for the carb as boost goes up. It runs fine with no supercharger, boost reference is atmosphere.

But, I’m using a known pump regulator combo. So, you might want to dig around for info on your pump. I’d hate to see you burn that up.
 
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I think my only choice on the car now is either run what I got or replace it with a carb... nothing is available before late June, which is too late to test and tune before driving 800 miles.

And it doesn't seem FiTech is in any hurry either - so the only, realistic choice is probably a carb....

I've got a spare Holley 950HP Ultra that I never used, if you need it. It's been sitting a while, but it has never had gas in it. I also have an unused Barry Grant HP fuel pump (BBC block mount). Barry Grant went out of business a few years ago due to personal legal problems IIRC, but he made great high performance fuel system parts.

Originally I was planning on a carb - mostly because I already had it (850 DP annular discharge) - but I have it and the fuel system. thanks, though.
 
I’m using a fuel injection pump and the bypass regulator is set for a carb.

You have to do this for a boosted application with the regulator boost reference, then you always have the right delta pressure for the carb as boost goes up. It runs fine with no supercharger, boost reference is atmosphere.

But, I’m using a known pump regulator combo. So, you might want to dig around for info on your pump. I’d hate to see you burn that up.

I think I'll plumb in a lower pressure pump, I have a Holley black that I was going to use with the carb - I'll simply pull through the in-tank pump.

Again, all of this is under "if" .... I hate it when I presume people will call back in 24 hours but Monday, since I didn't actually ask 'when are you going to call back' I'll find out FiTech's plans.... once that happens, I can move forward.... I may carb it anyway on Sunday, but we will see....
 
So I bought the Holley equivalent of what I have now. Yesterday FiTech called back (which was nice), but in the conversation the person said "well, I don't know why it's coming back, I wouldn't have allowed it." "Well, your computer that you installed burned up, then the second computer that you provided didn't work right".... he never backed off that initial statement. Fine, I get it... go pound sand. While I might be surprised, I am already hearing the words "it isn't our fault" ... fine, as a customer, it's my money that fixes the problem and you don't get any of it.... add to that the great advertising that I'll be giving when I show up (if) in Utah, and their business model seems a bit nearsighted. But it's not my company... so they can do whatever they want. I could say more, but I'll save it until after they get the chance to somehow blame me for all of it, including the mis-machined throttle body.
 
I am still baffled by how poorly these companies execute their EFI products. It's pretty simple, this isn't putting a man on the moon technology :smash:
 
I am still baffled by how poorly these companies execute their EFI products. It's pretty simple, this isn't putting a man on the moon technology :smash:

maybe Holley got it right... that's my hope. The FiTech can go on my abandoned EFI shelf, it will have plenty of company. There's a Holley Commander there, a B&M system, a FAST Ez system, an Accel system, and several GM systems....

what's fun is the only system that didn't get removed is the GM systems - granted, they got removed because reprogramming them wasn't an option (well, except the LS system)...

tits or tires...
 
I am still baffled by how poorly these companies execute their EFI products. It's pretty sim ple, this isn't putting a man on the moon technology :smash:

Respectfully, I must disagree. Whether you're making a microprocessor based system to control a car powertrain, or control a lunar lander, the principal is the same. The control module/box is tasked with reading all the sensor inputs, and responding accordingly. To do this reliably and consistenstly it has to be designed and manufactured correctly. The design guy needs to know all the electrical and environmental parameters/ranges that the box will potentially operate in (during both normal and abnormal conditions), and specify/use the appropriate parts in the construction. And then it's up to the manufacturing group to build the controller with correct and consistent processes that will produce a product that meets the calculated/designed reliability. And then it's up to the Test/Reliability guys to beat the hell out of the part to try to find out if there's something the designer or manufacturing guys did not anticipate.

I know you know all this, I'm mostly typing to the collective buyers of electronic parts. I admit my bias regarding aftermarket electronic equipment, but I also believe they often don't use or have the resources to do the job "correctly" to produce the parts quality that the customer expects.

JMO. (and worth what you paid for it. :amused: )
 
Picturesedited
130ish mph, nice thing, not hitting the fender (front or rear)... bad thing, probably need bigger sway bars
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the dragging thing underneath is my tow strap...edited
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​​​​​​​going away
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btw, that top picture is at 130 mph


FiTech

I called them today, they're testing the throttle body now. According to them a TPS wire was pinched - which may have caused most, if not all, of my issues with the TBI.... of course, my second, followup question "so, what about the computer that failed?" they hadn't tested it yet... I'm still glad I bought the Holley because it gives me an outside chance of being able to run next weekend as it's going to be delivered (by UPS) on Monday.

as for the 2nd computer.... think "boy, that'd be great to use as a controller for a stack-injection on something silly like a nail head Buick motor....."
 
so, the new shop supervisor is getting a handle on the expectations
Luigi
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I'm not sure these will taste good
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make with the treats
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time to remove the center block
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I think it's been part of the issue with maintaining good temps
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the only way I could figure to clamp it
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I still don't know what the sides will look like...edited
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typical boss, sleeping on the job
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FiTech.

They're sending my units back, they found faulty software on the 1st unit and a pinched wire on the 2nd unit.

I'm done with them. I can count the number of failures of the system and it's not looking good for them - getting yelled at by the warranty person was a nice touch too (let's of course, remind that phone call last Monday where the rep said he couldn't imagine why they authorized a RMA... wonder if he's going to call back and apologize? lol). They claim Holley uses 'their' system... well, okay, but Holley wasn't failing at the track; FiTech was. Their entire defense is "well, we fixed our mistakes".... did you? they have no idea why the software corrupted on their system - so whatever the problem is, it will happen again. In their testing they found the fans didn't turn on (even more scary), but once they reloaded the software "it was fine".... so much for that tune that they just deleted, right?

the first thing I noticed about the Holley system... the wires seem appropriately sized. FiTech claims you can run the fuel pump off their wire (an 18 ga wire) - anyone want to bet that's where the corrupting voltage spike came from? after all, I was at full song at the race track (thus pushing the pump pretty hard).... anyway, as I said, I'm done with this system on my C3. It will go on the shelf for another project... like all the other EFI systems on my shelf...
 
calm before the storm
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now it's getting serious
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thankfully I have access to my fuel pump
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ran the wire down the center console.edited I'm going to put a switch on the dash to turn the pump off
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show wiring it is not
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I swear I'm going to rename this Corvette Aaron's donkey (referring to Balaam's donkey of Biblical fame). UPS - "we're running late on next day air"... had I got the parts today, I'd have it running by the weekend and potentially able to run an Autox.... now, not a flippin' chance.
 
this is just a test of your flexibility and your doing way better then i would be. i think i'd be in the corner shaking with grief or madness or both...
 
this is just a test of your flexibility and your doing way better then i would be. i think i'd be in the corner shaking with grief or madness or both...

To borrow a saying from one of my favorite authors, Douglas Adams.

Taking a vacation from your senses does you no end of good.

anyway, onward
And then the parts arrived...edited
so I know I'm tearing this apart... but I'm fixing several issues at once.edited Obviously the EFI, but the fans need to be on a switch and the fuel pump needs a switch for off too..edited
but first, dewire several wires I don't need
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it arrived, but missing one part.... the clear cover for setting the various angles with the distributor... thankfully, it can be guessed...
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calm down, this is temporary so I can build a shelf here.editededited
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unneeded wires
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controller goes inside
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puppy snoozes
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