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1994 Dodge 4x4 - tune Up - Photo 9299865

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Mark Macneil never starts a tune-up by just throwing the ride on the dyno. He first questions the customer on what the vehicle is doing and how it is acting to get an idea of where to start. Once that is established the vehicle is put on the dyno and a base run is made.

131 0707 01 z+1994 dodge 4x4+rear view dyno

131 0707 01 z+1994 dodge 4x4+rear view dyno

131 0707 03 z+1994 dodge 4x4+unichip q plus

Mark Macneil never starts a tune-up by just throwing the ride on the dyno. He first questions the customer on what the vehicle is doing and how it is acting to get an idea of where to start. Once that is established the vehicle is put on the dyno and a base run is made.

Once Mark got a base run on our red Dodge, he installed the Unichip and made a "no-change" or "zero-change" before he adjusted anything just to make sure the Unichip and truck were working together correctly. For the fuel mapping adjustments (pictured screen), the Unichip can make changes in 200-300 rpm intervals and in multiple throttle positions.

Macneil of The Dyno Shop is an old pro at this, having worked with Unichips long before we brought him our jinxed truck. Macneil located the correct wires and cut and spliced where necessary. Two wires from the Unichip control fuel mapping and are run in series between the engine and ECU. Two wires are also run in series for timing control to advance or retard spark. A single wire run in parallel is hooked up to the TPS (throttle position sensor), and two wires are run to a hot ignition lead and for a ground.

The Unichip control box is no bigger than an MP3 player, and should be naturally mounted as closely to the factory ECU as possible. Macneil shoved it up in the highest, safest place on our firewall, knowing that this was an off-road truck that will see a lot of dust and grime.

As we stated earlier, the universal Q-Plus unit we were dealing with has no preset parameters so it can be custom tuned to meet an engine's needs. These Q-Plus units must be installed by a Unichip-authorized shop that has a Dastek Co. tuning module (call Unichip if The Dyno Shop in Santee, California, is out of your driving range). The tuning module is used in conjunction with a dynamometer to test how an engine will adhere to changes in fuel or timing. The two rotary knobs on the box simply retard or advance timing and change air/fuel ratios without burning them into the Unichip's memory, allowing Macneil to tune with much more efficient trial and error.

Once the driveline was back together, Macneil was able to tune our engine with the Unichip. What he found was considerably more power from just tuning the truck with the Q-Plus box. Macneil also found that our Dodge was still running lean at top rpm. We had already boosted up from the stock 16-pound-per-hour fuel injectors to a 24-pound-per-hour set of Holley injectors though. A call was again made to Holley to switch out for some 32-pound-per-hour injectors so the full power potential can be gained at high rpm.

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