CarbTree

Newbie with GM security shutdown. If we grew up through the 60's and 70's we could sand our points clean, set by eye, and still cross country. In 2015 I bought a Tahoe 5.7 in great running shape, and today I count 13 weeks sitting dead, five techs failed to do a successful security bypass, so it's up to me? The dealership wants to swap out all the components, perhaps it costs $3,500. You can say I'm impractical, but if I can't save the day right there on the side of the road, the OEM went wrong for us all. How many people are one paycheck away from a foreclosure? In desperation I am building a carb tree with lawnmower carbs strung off the plenum, and if the computer also shuts down my spark, I'm still dead. Laugh, but I ran a Ford van on one 4hp carb at 35 MPH. I'm looking at motorcycle fuel injection to upgrade from my carbs. There is a workable simplicity there, cost is lower, I can run with redundancy and NEVER AGAIN BE TRAPPED with a GM security shut down. I can hide a clever cut off switch or two and my old Tahoe will never be stolen unless towed by thieves. But I seek help in this effort to re-engineer the 5.7 controls. In the end I will be an expert at the new system and I will help everyone else BYPASS GM IDIOCY. Practical people with greater expertise, please contribute toward this worthy goal of the common man. Thanks.

JosephIV

iTrader: (14)

Did you drink a wee bit of liquor before posting? At any rate, welcome.

CarbTree

I'm an innovator and I prosecuted my own patents before I realized our system does not readily promote inventors. Maybe its the greed, rather steal a dollar than make the million together. Seriously, I do seek a clear thinking, humble peer group of people readily extending benefit of doubt upon potential friends who might altogether promote the common man of any size hands and admirable maturities. But humor is accepted, and thanks for reply. Today I am looking at these 12 HP carbs and wondering if they run better reverse than forward because I can use the throttle plate to shut the main jet off from the engine draw low pressure and yet MAYBE get good idle control by plate rotation. I'm using the Chevy throttle plate as original, no change there as yet. Now, maybe someone has experience with those side draft VW carbs that sell reasonable and these would do so much better for me. My hood sits tight over the engine and I have little room over the manifold. My fabbed carb tree is doing good for room on the passenger side of the engine. If there was a cheap, reliable aftermarket fuel injection to go QUICKLY onto the 5.7 and GET RID of the GM electronic components, I am totally ready to hear from people who had a GOOD experience with all of that. So far in my searching I do not see the inexpensive aftermarket system. If there have been twenty million people trying find the solution to the GM nightmare (YouTube hits) then I think this solution will SELL SELL SELL when it is perfected at a price point under a thousand bucks and IS USER FRIENDLY. The crusade is on. Photos available, just ask.

jimmyblue

iTrader: (11)

There is/was an outfit that sold a HEI distributor
conversion for LSx engines, used a "spud" on the
cam snout to drive the distributor. This plus carb
and you have a self contained standalone setup.

Also there are add-on ignition systems that use the
reluctor wheel and these are probably better for
spark quality.

4150 style intakes are out there if you want to run
a Dominator carb. I'd expect there are square and
spread bore Holley compatible ones too, somewhere.

There are some aftermarket EFI setups, MegaSquirt
etc., that get some play here on the site.

But all that aside, seems like you ought to be able to
either relink VATS, disable VATs or maybe you just need
a proper resistor-chip-value key - do you have any idea
what the cause of failure really is? Data bus or some
simpler explanation?

JoeNova

He said he has a 5.7 tahoe. It's not an LS based engine.

CarbTree

At the dealership a wonderful, very consumer dedicated guy told me the new GM cars are even worse, more parts relating to the shutdowns perhaps, I didn't push and waste his kindly time. He indulged me in providing the entire schematics other than the circuit boards within the actual computer. Yes, I can make some sense of them all, but to what end? It will take some time to pinpoint the jumpers I need to go from specific pin to specific pin. SOMEONE OUT THERE HAS IT DOWN. Among my techs, the first went the "cut wires, install resistors" route. The others basically endorsed his work, caused me to purchase parts as a skip-work, and ran upon their failures. I do not have a chip key, it has always been a two dollar key available at Home Depot. My day of initial failure hit me fast when I both turned the ignition and flipped the master door lock. The engine raced and died, and I immediately wondered if the five door solenoids ran a reverse pulse that killed the system. People say most likely a ground fried open. I have to tear the car apart everywhere, or some such complex mess.
There is a guy selling dual 46mm throat injector bodies, looks like a complete system for under a thousand bucks. But I have to get a different manifold onto my vortec engine. A few sellers are claiming their distributors go into the present vortec manifold just fine and stand alone. Money is always tight for me, and I enjoy doing research. So far I am gathering motorcycle fuel injection components and I see mostly how to make it work, new field for me. My goal is to have these (carb tree and throttle bodies tree) hang from the stock plenum at my whim on the side of the road when the VATS kills me again at its whim. If someone calls me with security shut down, I have my carb tree ready to mount and the car drives home again. At home depot the 3" black flexible connector for plumbing actually fits the air ducting. At any fire extinguisher supply, the old 3" canisters are just the right diameter. Stainless, I think. I bore them with a bimetal core drill and epoxy on my carbs. I get four carbs on one length of 3" steel tube and the end of the tube allows for a backfire safety pop off. If the plumbing connector burns easily, that could be a mistake, but wrap tin foil where it seems healthy practice to suppress fire.
Those of you with side draft carbs laying about, I'm telling you, unless you need a race car, this approach might save the day for about a hundred bucks in miscellaneous parts. I do not have my fuel supply figured out yet, as to where I tap into the high pressure with a regulator set at 2 psi to fill the carb float bowls. That has me a bit intimidated, fear of mistake that forever bugs me. I'm also trying to conceive of the simple physics method to shut off some of the side draft carbs when I am at idle. I need only one carb at idle. I can put the butterflies back in and try to string them to shut off sequentially, but maybe there is a clever cluge by change in air flow. Now I'm really curious about those nice 44mm VW side draft carbs. Someone might advise me about their perfections and simplicities. They look so logical. Wow. Next good paycheck and I should get one. Our efforts will eventually benefit many, many people, once we defeat the GM debacle with a user friendly solution.

CarbTree

I see a $1200 Megasquirt system designed for LT I think. Maybe someone can comment as to the good qualities of this conversion. It has to be more user friendly than the GM system (which is a cruel torture against consumers). I have to keep the tranny shifting correctly and I think the old distributor can also stay put. If the spider injector is kept in place and used, this I expect. I'm wary of that design, I hear they can fill your engine with gasoline. My preference would be for a throttle body that goes directly onto the round throat of the vortec manifold and maybe I can spot any gas leak so my engine never fills with gasoline. Any failure mode catches my ire if I can not fix it myself on the side of the road, or keep the car rolling by a practical trick. Having a fuel pump inside the gas tank is not my idea of good design. But I am very impressed with my 99 Tahoe and 96 Suburban for their strengths. Good frame, good power, good trailering power. These cars should not go to scrap because the VATS has them rather permanently and repeatedly broken beyond reasonable remedies. A home security costs $20 to $30 per month (free installation often) and when it triggers you get to use your house again, quite immediately. Not expensive to remedy. But my Tahoe, dead fifteen weeks and the cost to replace everything is over $3000 I think. Five techs have failed to fix it so far. I do not have a chip type key cylinder. The spliced resistors have been tried, did not work. There are probably 300 points of failure (engine shutdown - failure modes) designed into these cars now. This overall design is nuts and NOT NECESSARY. It is not user friendly. I need a plug and play, user friendly system. When my VW carb (44mm double throat) gets here and I mount it to my carb tree, maybe I get good idle and good road speed. The 12 hp carbs I started with are not idling well enough and the wet gas remnant poses a fire threat. But it would do seventy miles per hour no problem. There is not one change to the engine other than to hang these carbs off the plenum. I can put the carb tree on in two minutes and when my fuel pump dies or my "fixed" VATS shuts me down again (another $3500 at the dealership?) I can run quite immediately again on gravity feed carburation. NO REAL CHANGE TO THE 5.7 engine and plenum, no big expense to roll down the road. I have seen people part out their car because of the repeating security shut down problems. I have talked to many people who suffered repeat shut downs and sold the car to be done with it. But GM now only offers us this INSANE SYSTEM? Why not something as user friendly as home security? The cops come and you get the car started then and there. But no, the car never runs again unless I spend a ton of money at the dealership. I will prevail and those of you who are laughing will one day direct your friends to me because you can't get them up and running this easily for a couple of hundred bucks. These are good cars except for the inherent GM failure modes. It will happen to you again. And again. And again. It never end$ unless we bring about the solutions. I need the complete and final, user friendly solution to the GM debacle, and I need a flexible travel beast I can ALWAYS save on the side of the road in short order. How close have you gotten so far?

jimmyblue

iTrader: (11)

In all of this wall-of-text I have not seen a simple
statement that anyone reached into the tune and
disabled VATS. If that's the main beef, seems like a
thing to try.

My '02 Vortec van has similar sounding hardware and
serial VATS in the factory tune. It does not use a
"chip" key, which (if your rigs are the same) may be
why changing resistor values does nothing - they're
not being looked at?

CarbTree

It was six months before I got the Tahoe working. The dealerships were going to take me for over $3000. I found a guy who hooks to the federal database and removes the security system from the computer. I think he puts the owners name in the database, and if you steal cars with your computer they come after you. Total cost $150. Thanks to JimmyBlue mentioning VATS. It still took me weeks to figure it out and succeed. The car seems to run better than before. I think the security was chirping my fuel injection.

After building several carb trees I came to a profound conclusion: Carburation dumps a lot of wet resin onto the pistons, it thins the oil, and the engine wears out more quickly. Propane engines last forever, no wet resins. My carb tree project would next evolve to capture the wet resin and run it over some hot surface device, evaporate it, and send it to the engine. The logistics are not perfectly trivial, if you get a fire started then what next? I imagine a few people coming down off Pike's Peak had a backfire and then fully torched the engine to slag as they engine braked. It does not happen with a spider injector.

I bought a Blazer a couple days before I discovered my computer tech. It was running on three cylinders, low mileage, so I thought I made a great buy for $700. New plugs and wires and distributor DID NOTHING. Now I am convinced that the spider injector was subjected to extreme heat after the engine had an overheat event. People tell me they have found the spider injector melted and closed against fuel flow. It is not trivial to replace the spider. Bad design. No ability to verify it visually for failures.

But this wet resin problem still exists somewhat with FI. The Tahoe (any FI car) can run strong at 400,000 if the wet resin is very minimal throughout its lifetime. Propane solves it completely.

CarbTree

I am pondering FI polarity in the 99 Blazer. Readers will see my Tahoe debacle... So my original crusade is temporarily suspended (Tahoe runs OK with original spider FI now after I had the security protocols removed from computer for $150) and I can hear some goofy pressure wave play out through my exhaust. Some of FIs are working weakly, probably. Can is burning fairly clean, passed inspection but the DIFFICULTY checking my spider injectors drives me mad.

On the Blazer I can not easily repair a leg of the spider by myself. The upgrade I bought had a broken high pressure line, so I bought one new injector. It does not seem to press in all the way, I used a bit of vasoline and the metal clamp does not fully seat the new part. The other five seat well. Then I had the idea to put switches on the wire harness so I can switch off single injectors for testing. But then it strikes me that there is a polarity consideration. When I search forums for this issue, there is controversy. I am hoping the pintel metal remains generic, not polarized (magnetized) and so there is NOT A POLARITY ISSUE. There may still be a field collapse issue, and someone who really knows this stuff should post a major expert explanation with no blind spots in it. To just post and not reflect on your own failure modes is not all that helpful. I will be happy for anything added after my post, and in the next week or so I might get the Blazer put together. I'm still very certain I will violate my wire harness and put switches in line to shut off injectors (look for the bad ones this way?). The new thread if placed should have a title such as INJECTOR POLARITY and RELATED ISSUES EXPLAINED and it should read true about pintel magnetization and field collapse damage to computer. If a pintel magnetizes over time, then old pintel or a reman pintel IS likely POLARIZED! This will affect performance if not assembled correctly. Maybe computers are designed to compensate. And I am still oriented to vaporizing the fuel completely (not traditional FI therefore). The day will come when I have such an engine, or I will be electric with perfected generators.

CarbTree

While I did just add a post to my old threads, over to the left the control box says I have ZERO POSTS. Hmmm... Anyway, I am hoping to grab an expert to fulfill the title above!
I am considering if the FI spider pintels become magnetized, and if there is then a polarity issue. The wiring is then critical, perhaps. Also, a member suggested there is a field collapse issue (computer damage?) if the wiring is done wrong. When I examine the wiring harness, I see 6 similar wires and 6 color coded wires, so if I put in my own switches for testing FI at each cylinder, do I also have to worry about that field collapse? My original computer failure was perhaps based in field collapse (door lock solenoids maybe ran high voltage back through system) and "Crusade Begins To Eliminate GM Security..." So, I am looking for the definitive answer on the pintel magnetization which forces the wiring polarity upon me before I can just slap the manifold cover over it all and turn the key with total success. Maybe I need to add some protection diodes to the harness, but it would be great if the computer has them built in! Thx

pantera_efi

iTrader: (1)

Hi Tree, I invented (a team member) the FIRST MODERN ECU in 1984 (60-2 DIS and EFI).
I have fitted many GM engines.
Your Choice ?

Then there are the guys who "flash" OEM EMS. (MANY)

The VATS is removed, my guess is that this is IMPORTANT when the GM engine powered Race Car, GM "SPEC" EMS is fitted to a car that DOES NOT use a KEY switch.

Lance