Frequently Asked Questions

I was wondering if you can make the SECU for force-induction from an 88-91 Si, 88-89 Integra, or JDM ZC ECU?
Yes, The SECU can be made from any ECU with the following center three digit part number: PM6 (Preferred), PM8, PM7, PR4.

Is the PM5 (88-91 DX) eligible for the SECU conversion?
No. The DX only drives two injectors.

If after the new ECU is purchased and I decide to upgrade the engine with either head work or a turbo/bottom end build up, can the ECU be reconfigured and what would be the ball park cost of that?
If you plan to "tune as you buy", please consider the Gold SECU, this allows you to retune the ECU like an aftermarket EFI each time you reconfigure the car.

I have a 1990 B18a non-vtec block with a B16a vtec head, 90 Prelude 2.0 crankshaft, B16B Civic type R intake cam and Integra Type R exhaust cam. Do you have a preprogrammed ECU for this?
One word.... SECU.

I know this project has been a great undertaking. But $900 for the SECU is fairly steep!
For what it does this is a damn good price! Consider the features it gives you, and the part cost it eliminates: ignition retard device (about $200), large fuel pump (about $150), rising rate regulator (about $100), after market 3D EFI system (about $1000), wiring, install, tuning just to get running with an aftermarket EFI ($600), NOS RPM saftey box ($200), and VTEC RPM switch ($200).

We are talking about aftermarket EFI ability (Full 3D linearly interpolated tables). But installs easily, has been coined by some as "plug and play Honda EFI", supports sequential fuel injection (not batch like most EFIs), boost retard/fueling, and NOS. It already comes plug and play ready: starts, idles, warms, and drives your car to the same spec you already run. You don't have to change out your harness, sensors, or loose stock tuning. You can start tuning for more power right away, instead of spending weeks tuning the EFI just to get the car down the street.

I'm about to do a B16A swap into my 89 Civic Si and I'm getting the Si-R ECU, can you modify that one into a SECU or do i need to keep my Si ECU and then you can make it B16A Turbo Compatible??? Let me know since if I don't need the Si-R ECU I can save me some $$$ and use it towards the SECU Gold Version...
Save your money and time spent searching for that JDM B16A ECU! The SECU is available with VTEC control and tuning all from a USD core.

What is the reason people use check valves with a turbo kit? Or a black box? How does this trick the ECU?
The check valves are installed to bleed off pressure from the MAP sensor's vacuum line so that it will not produce a voltage over 3.1v which in turn will cause the ECU to flag the MAP sensor faulty and fall into an undrivable limp home mode (where it ignores the MAP sensor completely). The black box is an electrical way of making sure the ECU never sees a high voltage from the MAP sensor. All of these things are lying to the ECU to tell it it is at 0BAR not boosted. Forget these tricks, get a SECU and let the computer see and work with boost!

My main concern has been accurate fuel delivery at varying boost levels. I don't want to have to modify my fuel curve every time I increase the boost level. Is your SECU capable of adapting a fuel curve on the fly to compensate for changes in boost pressure and atmospheric conditions? Will it adjust itself for less fuel and advanced timing when under low-boost conditions?
The Silver and Gold SECUs look at the amount of boost the car is generating and figures a correct fuel pulse and spark advance - how it calculates this is adjustable with the Gold SECU. So the same "tune" can be used for 1psi boost as 30psi of boost.

So you guys change the way the MAP sensor reads positive pressure so it can read up to like 10psi? So there is no reason for the check valves or ignition retard/advance anymore. Correct?
We do not change the way the MAP sensor reads pressure. We change the way the ECU reads the MAP sensor. We change the functionality of the ECU so it will retard timing and add fuel as boost increases. This is more like how a factory Honda turbo would operate. This is what we strive for: a forced induction system, without compromise, just as the factory would have done it. Any rising rate regulator, TA sensor resistors, retard boxes, or check valves are removed. Large injectors are installed, and the ECU takes care of forced induction management in a very clean setup.

For what boost is the stock MAP sensor good for?
The stock map sensor on (88-91 USD cars ) is capable of boost to about 10 psi. 2 and 3 bar map sensor options will be available shortly.

Will the stock crx si fuel pump be sufficient with the 450cc injectors, or should i keep my oversize pump?
First consider that many factory turbo cars have a smaller gph pump than the GSR. Although there is an increase in fuel volume, the pressure increase is not there, so the stock pump can usually supply the rail without difficulty. People only need "large" pumps to supply the high pressures of a turbo kit that is using a rising rate regulator. The SECU kit removes any rising rate regulator and brings pressures down to a 1:1 differential pressure with manifold pressure/vacuum.

I was using a Rising Rate Setup and I had previously installed a high volume fuel pump for the high pressures. After reading your Test Procedure for Factory Specification Fuel Regulation document, I installed a fuel pressure gauge and I can see that my fuel pressure never gets down to factory specification! I can even see my fuel pressure fluctuate with voltage (such as when the alternator switches in and out of charge state, or with the head lights or turn signals).
The fuel system is a SYSTEM. People forget this quickly. Changing any single part of the system effects the rest of the system. You need to see those low factory fuel pressures at idle for proper fueling at idle and cruise. If you are not seeing these values, especially if your pressure seems to be voltage dependent, then your fuel system does not have fuel pressure regulation which is a serious problem.

A factory pump and regulator combination has no trouble regulating pressure regardless of voltage. The problem is your combination of regulator and fuel pump. Simply, a regulator that is faulty or unable to return flow the excessive volume from the oversized pump. You have three options: factory pump, pump which doesn't overly exceed factory flow volume, or try to replace the factory FPR with a unit more capable of regulating the high volume fuel pump - an adjustable pressure baseline but a 1:1 rate.

At what boost do I need to upgrade my fuel pump?
There are so many variables, you should test your particular configuration yourself. In general, depending on the condition of your pump and filter it may be necessary to increase fuel pressures or pump size in the 12psi boost area. Use an electrically isolated fuel pressure gauge, and keep an eye on pressures yourself. If the pressures are dropping as boost increases, upgrade your pump or clean your filter, otherwise save your time.

A popular injector resale house convinced me to buy $400 worth of Disc style injectors with a much smaller delivery than you recommend, now what?
They sell those injectors for two reasons: 1. That is what everyone is buying, and what they are selling. 2. The 310cc is just about the largest injector a stock ECU driven Honda can limp around town on.

The SECU package comes as a pretuned kit when ordered with the 450cc pintle injector option. This is just about the largest injector you can use and obtain a respectable idle.

The Gold SECU, like other adjustable 3D EFI systems, can be user tuned to work with any injector. 310cc injectors are likely too small to run at normal fuel pressures into 9lbs boost. Their use may require an increase in baseline fuel pressure, or even a small amount of rising rate rail increase.

The pintle injectors provide a more burnable, atomized plume compared to the laser spray injectors. Although laser spray injectors may be suitable for race situations (high RPMs), we recommend pintle injectors for their atomization at low intake velocities, low pressure, and small pulse widths.

I NOW believe that I need more fuel for my turbo kit. Do I need to have your computer to run the injectors that you are selling? Can't I remedy the over rich fueling with the SFC function of the Field controller?
Units such as Field have only a small adjustment window, as they manipulate the stock MAP sensor line voltage. The injectors are large enough to fall outside this window. For instance, the injector will need about 40% leaning, the Field can only go, what 15-20%? You will be able to drive down the street - but the tune will be about 20% rich across the entire power band (even at idle and cruise if closed loop can't tune it out), washing the cylinders with gas - removing oil --- reducing horsepower greatly ..etc... You could also try to replace the factory regulator with an adjustable unit to bring down the fuel pressure baseline to about 18 psi to try and cure the situation. Over all - a nightmare... remove all these patchwork devices - sell them - and install the SECU.