Back to Uncategorized

Engine Computer (ECU) Programming


Performance ECU Upgrades



The Ash-SPEC ECU upgrade has become well known in the Z32 community for offering reliable power with factory drivability while maintaining factory safety features. We offer dual program setups as well as an integrated boost control feature. Safely increase your Z’s power and torque output with increased boost levels and a properly configured program for your car’s modifications!

Upgrading of the ECU consists of removal of the OEM EPROM chip containing the ECUs program, installation of an EPROM socket for ease of chip replacement, and installation and testing of a new Ash-SPEC EPROM. Some later model ECUs require a custom AshSPEC daughterboard to be added into the ECU to allow integration of an external memory chip which can also be easily swapped by the user. We offer our ECU upgrades at the same price for all models.

Upgrades are available for both NA and TT models, 5speed or automatic, and vehicles will pass even the most stringent California emissions tests – guaranteed!

The Engine Control Unit (ECU) is a dual-processor computer which monitors all engine sensors and controls all engine functions for fuel delivery, ignition timing, rev limiter, speed limiter, valve timing control, emissions control systems, and more. This computer operates based on a set of values of which Nissan generated in their R&D; process of the powerplant, however, they left a lot to be desired by the enthusiast. In our upgrade process, a new program catered to your vehicle’s modifications is generated and installed. Programming which allows for safe running of higher boost levels while maintaining “safety mode” configurations allow you to improve performance in a reliable fashion – a programming standard set by AshSPEC back in 2001.

The Ash-SPEC ECU upgrades were developed using the ZEMulator to finely tune operating engine parameters in both street and dyno conditions using a wideband O2 sensor setup. The utmost care has been taken in the development of these programs to ensure that the program you receive ensures performance, reliability, and safety.

Due to variations in fuel quality throughout the country, we have constructed a set of programs tailored for fuels having less than 93-octane, minimum of 91 octane. If you have 93, 92, and 91 octane fuel all available to you and are trying to decide if you should get a lower octane program to save some money on fuel, keep in mind that the 93 octane programs are the optimal choice as they will produce better power and torque.

We offer our ECU upgrades with the option to have two separate programs that can be switched by way of a small toggle switch mounted into the ECUs aluminum frame. The ECU can contain any two different programs you desire. We typically configure the 2-program setup with the following setups:

Pumpfuel & Racefuel: Pickup an extra ~40-50RWHP with racefuel!

91-Octane & 93-Octane: Not everyone always has access to 93!

Pumpfuel & Valet/Security: Valet/Security programming has a 30MPH speed limiter and 3000RPM rev limiter!

We have developed an electronic integrated boost controller for TwinTurbo ECUs that utilizes the OEM boost control solenoids and retains the factory safety boost feature! This setup has a remote adjustment knob that allows control over the boost pressure the turbochargers produce. Boost jets are still required with the integrated boost controller to allow higher boost pressures and we will provide the ECU upgrade with appropriately sized jets based on your fuel injectors. For stock injectors, we provide boost jets that offer a boost control range from 7psi to 15psi. For those with upgraded injectors we will provide jets that provide a range of boost from 7psi to 18psi.

Ordering Information:

STANDARD ECU UPGRADE: This option is for those who will be sending their ECU in to us for the upgrade service to be performed. If you cannot afford to have the car down for a few days to do this, we offer the ADVANCE-CORE Upgrade Option.

ECU UPGRADE WITH ADVANCE CORE: We will send out an ECU already upgraded to eliminate any downtime. Once we receive your good ECU back we will refund the core charge. Lead times to shipment are contingent on core availability at the time you place your order. We have a limited number of cores and may not be able to process your order until we receive back a core from a previous customer. If you are in a pinch and must have this immediately, please contact us to check for core availability.

ECU REFLASH: We offer ECU reflashing for AshSPEC ECUs for $100 per incident, so as you go through your modifications you can have the ECU reflashed to maintain proper programming for your setup. We offer this in two varieties: Standard Reflash and Advance-Core Reflash. The Standard reflash requires you to send your old chip in to us – when we receive it we will ship out the new chip. The Advance-Core reflash is to minimize your downtime as we will ship out a new chip to you with the proper programming. Once you install it, send back the old chip and we will refund the $100 core charge back to you.

Advance-core options require that the core item be shipped back to us with a postmark no later than 7 days upon arrival of the original product. Core items that are returned to us later than this will be subject to refusal and returned to sender at our discretion.

When shipping your ECU, please remove the mounting bracket that holds the unit into the vehicle. This bracket makes for bulky packaging, which ends up costing more to ship. We strongly recommend using USPS Express Shipping as well since they arrive to us earlier in the day than UPS or Fed-Ex. USPS has a cushion mailer pack, 7″ X 10″ that the ECU fits perfectly inside of – put your ECU in this packaging and then put this into a Flat-Rate envelope. Be sure to add an additional $100 to the insured value in the event the package is lost or damaged.

Our location is guaranteed overnight delivery with the USPS Express service from 95% of the continential US and will cost you about half of what UPS or FedEx will charge for overnight service. We have had an incredibly reliable track record with USPS Express – not a single package lost!

Please affix a note to the ECU itself containing your contact information, vehicle information, modification information, and whether you need boost jets or not. This will ensure that the ECU will be upgraded in a timely and accurate manner and improve chances that it will arrive to you sooner. Printing out a copy of the Paypal sales receipt will suffice as long as it contains all of this information.

Shipping fees are added to prices at time of payment with options for ground shipment, priority shipment, or express shipment.

Some ECU’s can be interchangeable. Here is a list of what style ECU’s will work each model Z32:

1990-1992 (8 Bit)Non Turbo ECU’s are all interchangeable
1993-1995 (16 Bit)ECU’s are all interchangeable
1990-1994 (8 Bit) Twin Turbo ECU’s are all interchangeable
1995 (16 Bit) Twin Turbo ECU’s are all interchangeable

Mix and Match ECU’s:

-Any 8 Bit ECU can be used on any 1990-1995 Z32, but 16 Bit ECU’s will only work with the years that came stock with a 16 Bit ECU.

-Any NA ECU can be converted to a TT ECU for an upgrade so long as the ECU is 8 Bit. 16 Bit ECU’s will not work for this application, and TT ECU’s cannot be converted to NA ECU’s.

-An Automatic Transmission ECU can be converted to a Manual Transmission ECU, but Manual Transmission ECU’s cannot be converted to Automatic Transmission ECU’s.

Please contact us for any further questions.