Hey folks,

Just out of curiousity, I'd like to pose a question. I still have the HRC black box, but I've never had any problems. In fact, I've never hit fuel cut. Is it possible I got the only functional black box in existance?

I'm trying to put together a plan of action from what I can remember from 8 months ago. My long-term goal (next 12 months) is 15psi on a built bottom end. I'm trying to put together everything I'll need to purchase and estimate costs.

On the 8 injector setup, will I need to purchase the ML? Or do I need a specialty MAP sensor or what? It seems like I read that 14+ psi will destroy a factory MAP...yes?

What are you guys doing?

The black box is supposed to keep the voltage clamped below 4.9v or so to prevent fuel cut. The MAP sensor is used as a major input for the ECU to control things like air/fuel ratio and ignition. Boost will make the MAP sensor output 4.9v+ and the ECU freaks out because it's not made for boost.

The Missing Link is a check valve made by Synapse Engineering, that is to be installed between the MAP sensor and the intake manifold, which will allow the MAP sensor to "see" vacuum and not boost. This is now a must-have item even if you use the black box because boost will destroy a MAP sensor... especially 15+ psi!

You can buy it for $55 at group5motorsports.com or gottude.com/auto

"The Missing Link is a check valve" <-- thats what I was looking for. :thumbsup

Actually, you would be one of the hundreds of folks whose Fuel Mapper works well! Typically, the usual reasons for incorrect MAP readings with Fuel Mapper are faults with the car itself, and/or the addition of electronics (such as AFC) that change the total impedance of the MAP sensor circuitry, and therefore the threshold point of the setting of the Mapper.

For such cars that are HRC Turbosystem equipped, where MAP voltage is out of range, contact our tech support dept: 630-801-9065 afternoons, or email tech@turbosystem.com. We have a large complilation of info from the field relating to interfacing of HRC components with many other products, as well as common fault modes for the car itself. We can help you isolate and correct the problem, as well as recommend tuning tips to suit your particular combo.

Thanks,
BH

Well always solder your map connetions on the FCD. No twist and tape crap! IMO, using a check valve instead of electronics is a far superior way to keep the map voltage at its stock level at 0 psi. Unfortuately, i had a bad FCD, clamping my voltage to 4.1 volts, causing to run way too lean, regardless of my fuel pressures( even at 120 psi of fuel at 8 psi boost way back when). I'm sure there are many of properly working FCD's out there, but there still are many issues with them. Its ok Bill, we still love you man! :) (ps, supply the missing links in you kits :) )

I personally know of three or four guys that have had issues with faulty black boxes. (BTW, I have recently seen guys' MAP sensors fail as a result of being exposed to boost) This of course happened without any such interface with an S-AFC.

I have gone through three black boxes myself. My initial failure happened when I first recied the kit. It was never able to adequately clamp in the first place to below 4.7 volts. (I cam eto find this later on through understanding their function) My second fuel mapper failed worked fine for a year, and then a long time with an S-AFC. It eventually failed as well (and this was almost catastrophic in its results as my only bouts EVER with misfiring occurred due to being extremely lean). My third black box worked just fine with an S-AFC, but I have since gone on to bigger and better things without any black box or S-AFC.

Here's the thing with having a black box: Without any voltage monitoring device such as an S-AFC watching over your MAP sensor while using a black box, you never truly "know" if your black box is accurately clamping at ~4.x volts or terribly wrong at 2.x volts like mine eventually did. So Bill may be right that the SAFC can help a black box fail, but without an SAFC to monitor the box, will you risk your engine on the mere hope that it never will fail?

When mine did fail, I must have talked to Bill 3 or 4 times without either one of us knowing what the problem was. We went through EVERYTHING! It was really exasperating. I literally combed through every aspect of the ignition system, air intake system, the fuel injection system, and finally, the ECU sensors. FINALLY, I realized that little black box was the demon at the root of it all! I had thought about the "why's" and "what's" that cause the injectors to squirt in the quantities that they do, and in fact, it's a specific direct correlation with the MAP sensor. I had learned in conversations with Bill (who was extremely helpful and patient) that the black box clamps at around 4.X volts being close to atmospheric pressure and in turn, max fuel output to the injectors. After seeing on my SAFC that my black box was clamping at 2.x volts, I had both horror and joy come over me. So again, even though there might be theories regarding the S-AFC's interference with this item, without the S-AFC, HOW will you know when or if your black box fails without tediously hoooking up a multimeter to your MAP sensor under boost?!? (not fun hooking up a multimeter in this situation)

Therefore, if you want to drive around under hard boost, blindly relying upon your little siliconed together black box, probably equipped with a 10 cent zenier diode, hoping that it's keeping your MAP sensor both clamped at levels less than 4.7 volts while at the same time, holding that line ABOVE 4.x volts, be my guest. But take it from someone who's both experienced the misfires that can happen as a result of a failing black box and has also seen a substantial variance in its clamping voltage amounts, that this box isn't 100% safe or proven to such a degree that you should rely upon it to be a part of a long term system that walks the dangerous line of helping to deliver 100+ psi of fuel under boost with your brittle piston ring lands.

Once I was given the opportunity, I quickly unhooked that unreliable piece of devilry and sent it back to HRC, who was again, cool enough to send me another. I then sent away for a used Split Sec VC1 which never properly worked for me either. And then I came upon the Missing Link. This wonderful piece of simplicity and fine craftsmanship was as much an answer to my needs as was the HRC turbosystem a couple years prior it seemed. The ML, albeit, in many ways is technologically less sophistacted through its method of clamping boost (by mechanically preventing its introduction to the MAP sensor), teaches us, and specifically taught me, that trying to re-invent the wheel when it hasn't been improved upon to such a reliable degree where you should discard it, isn't always the best idea. Being someone who didn't have the knowledge or the availability of this item, gain freely from my experience! ( http://www.synapseengineering.com/ML003.html )

Again, I'm totally with Matt, Bill! We luv ya here! Your kit is outstanding both in many of its parts and the theories behind them, in regard to both cost and benefit. We just think some hopefully cost-effective "alterations" to the kit might be a good idea. :thumbsup

In my opinion, there can't a better source of communized information regarding the long-term usage of your kits than right here at 2GNT.com.

So you're saying I should get a missing link then.:wary :7

Does anyone know what the max psi the ML can take?

Good question, fellas?

Merely, quoting the web site for Missing Link:

"Produces infinitely adjustable boost pressures requiring
no adjustment to Missing Link Valve"

http://www.synapseengineering.com/ML003.html

Jason, how the hell are ya! Listen, in all reality, everything both of us are saying is true, which is to say the God's truth probably lies some where in the middle! :)

I merely strive to place the proper perspective upon it...while the Mapper is not a perfect solution, it would be wrong if folks dismissed it out of hand, as the total number of issues does remain small when compared to the hundreds of units that are trouble free, typically on vehicles with NO other mods or faults to this MAP circuit.

You'll remember, when I informed you of my findings regarding the user-induced variabilities with harness mods and other gizmos, and differences from car to car, that you offered to get back to me with new test results based upon the new information. Of course, you were never able to provide that data due to your car evolving beyond an AFC, but I should think you would not dismiss it either; maybe even share it and embrace it for the amount it was worth (your post above does tone out a bit dismissive towards these findings, just pointing that out, not pissed at you at all). I got the data anyway in my own testing, and this data is the foundation of my entire position regarding correct care and feeding of the Fuel Mapper.

The only other solution was to have folks adjust the unit in the field to suit THEIR particular car and/or combo, but I decided this was too risky...sometimes we are forced to 'dumb it down' to protect peeps from themselves, 'specially if they aint particularly knowledgable about how NOT to blow up their shit!

Anyhoo...just wanted to also mention:

We use neither 'silicone' nor 'zener diodes' in our unit (chuckle). We use dielectric potting compond intended for electronics, and only Motorola transistors (aint a diode in the thang). Since you brought up qualiity (jab!), I'd like to point out that each unit is hand soldered, and calibrated individually using a pressurized (10 PSI) real MAP sensor to a tolerance of plus/minus .05V.

As to boost induced sensor failures...with all due respect, if you cannot specifically verify that the sensor failure was boost-induced, it is improper to state that it was. Done some research here too, and came to discover that the incident of failure for these sensors is way above median average, even on stock vehicles...it just aint the best MAP sensor ever. Bear in mind that these sensors are initially designed to also be able to handle backfire spikes, which can be 50 PSI or more. Exposure to 5-20 PSI for short periods will not hurt them. If you saw one disassembled, you'd se how they engineered the membrane with a 'stop' ring to address this. BTW, the MAP sensors of years back were not as advanced or durable, and actually could be damaged in this fashion. Maybe old legends die hard...:P

The ML has not proven to be the 100% solution either...it has shown issues with contaminant buildup, and it IS a leak, sometimes of fuel and air, under the hood...a small leak, perhaps, but tell that to a hungry spark...

The Best Part: We are in development with Synapse, the makers of the Missing Link, to include it in our turbosystems. This may occur soon, once I am convinced that it is a superior solution to the Mapper. In the meantime, all I ask is that we dont fan the flames of discontent and concern HRC owners unduly about a problem they are 99% likely to not have. If I thought the Mapper was as much of a train wreck as described here form time to time, I'd have booted it years ago...you KNOW I just aint like that, if it was total she-ite, it would be gone.

The Best Part, Part II: Peeps with Fuel Mappers and AFC's can easily overcome the impedance issue brought about by the AFC installation. I know how! Just get with me via Tech Support and I will hook you UP!

Lovin every minute of it,
Bill


I still love ya Jason! The more I learn from the field, the bettah!

Yeah, Bill is right on the leak thing. Happened to me. My intake manifold was scored pretty badly around the MAP sensor hole. The ML was letting a massive about air by. Had to take a crap load of gasket sealant to the ML. :P