Overkill L67 PCM What is it? A performance PCM for supercharged 3800s, designed by a GTP enthusiast to bring your own modified Grand Prix or other 3800 supercharged vehicle to life and make your car more fun and safer to drive. Features of this PCM: -Part throttle and full throttle fueling specifically for your smaller supercharger pulleys -Reduced spark retard (KR) from optimized fueling and spark timing advance to address problematic areas -Lower engine operating temperatures from lower fan turn-on temperatures for use with 180 thermostats and optimized fan behaviour for both city and highway driving -Speed limiters removed and rev limiters raised -Performance Shift transmission shifting remapped for true driving enhancement -Redline full throttle upshifts -Delayed and more progressive part throttle upshifting -Quicker more responsive downshifting -Highway 4-2 skip-shifting enabled -Highway/City overdrive bogging greatly reduced/eliminated -Increased shift firmness for quicker shifting and sporty feel -Hazardous torque management removed or revised which can enable fuel cutoff during traction control enablement or abuse mode enablement from increased horsepower levels -Customized programs available for all modification levels from mild to wild Why is it so good? This PCM is the product of extensive R&D into the effects of modifications on L67 vehicles, way more than other current PCMs offer. The end result is a very comprehensive code change, designed around your particular modification combination. How comprehensive does this PCM get? Different transmission tables and fuel settings are used for THREE different throttle bodies (including Northstar and LS1 TBs), different spark tables for higher stalling torque converters, burst fueling is revised based on the size of your aftermarket pulley, these are just examples of how customized the coding can get!
This PCM introduces some very new concepts while encorporating features that people have loved about their aftermarket 3800 PCMs for years. How much is it? An Overkill PCM customized to your specific mod level (no matter how short or long a list it is) $300. If you are local within the GTA, incar tuning is available, as is dyno-tuning if your car is highly modified and you wish to pay the expense of a dyno. Core charge is $100, a core computer will be shipped to you and you must return your existing computer within 30 days to receive full credit. Those who take between 30-45 days will receive half their core charge back, those taking longer than 45 days won t receive any money for their core return as a new core will have had to be purchased to take its stocking place. Computers can be purchased based on agreement to the following: -If you feel your PCM does not perform to your expectations, please contact Overkill with a scan of your vehicle and a retune will be offered to correct abnormalities which can existing from car to car. Retunes will work off the existing core charge basis. -One free retune is offered up to 6 months after initial purchase to account for changes in modifications or repairs which may have effected the mechanical condition of the car for the better. A scan is most helpful in this area. Retunes thereafter will run between $50-100 depending on the size of changes required. Retunes will work off the existing core charge basis. -Since the car modding game is a very personal path and since each car is different in mechanical upkeep and modifications, the results cannot be guaranteed. While the PCM work is always done to the best of abilities, the user must ultimately take full responsibility for the use of this PCM in their cars and be accountable for how well the car runs. A booklet is included with each PCM purchase explaining what is in the PCM, what they can expect from it and signs that the car may not be running right, and if you feel something is not right it s your responsibility to contact Overkill and make aware any problems so that assistance if possible may be offered. -Your PCM may be returned in working order for a full refund within 30 days of purchase.
FAQ Why buy an Overkill PCM when I can buy a tuner software and do tuning myself? Firstly, tuning software is fantastic and offers you a tremendous ability to customize your computer the way you want it. Be aware however that tuning can be very difficult and you need to know more about what you are doing with a tuning software at your disposal than your normal AFC device. Many will buy a programmer and never work the software beyond its basic functions. The Overkill PCM is designed using multiple tuning software; you d be required to buy both to get as in-depth in the coding changes as this computer. The Overkill PCM also involves many proprietary ideas of its programmer, you have access to the parameters required to duplicate them but like an art it s a painter and not his brushes that do the work With an Overkill PCM, you get a computer that is custom coded to your vehicles modifications. Instead of an off the shelf computer code, you get one custom set up for your mods. How custom do my PCMs get? I have different transmission tables and fuel settings for THREE different throttle bodies, who would have thought those needed changing when you changed your throttle body right? I have different spark tables for different torque converter stall speeds, you get the idea! I'm confident to say my computers are the most comprehensive 3800 computers available. Is this coding an enhancement of an existing aftermarket computer? No! The base computer coding also differs vastly from the other aftermarket computers available. If someone were to compare the codes, they'd be as dissimilar as comparing to stock. Extensive R&D has lead to exclusive fuel changes, revised spark tables for KR reduction, remapped tranmission shift patterns in performance shift, boost control timing, removal of dangerous torque management settings (and more importantly, it keeps the good torque management as well), heck even fan control behaviour is proprietary!
These offer the spirit of existing aftermarket computers with revised concepts and some very new ones as well. These PCMs are, in essence, something very and absolutely new to the market. Will this program affect my ability to pass emissions? No, infact it has been shown that more highly modified Grand Prixs are more capable of passing emissions testing with this program. Will my gas mileage be affected? This will highly depend on your driving style. Under light throttle and cruise, your gas mileage should improve. Under moderate to heavy acceleration, your mileage will decrease due to the additional fueling used for performance increases. Reports of 30MPG on highway trips are not uncommon. Must I run high octane gas with this PCM? YES! You must run the HIGHEST octane you can find with this PCM, 91 is a minimal but Sunoco 94 is recommended wherever available. You should be running the highest octane available with AND modified GTP for performance and engine safety. What horsepower gains can be expected from this PCM? The gains of the PCM will vary from car to car based on its modifications, anywhere from 15-25 horsepower or more. Reason being is a proper computer tune will unlock power that already exists in your car, while providing more reliable performance. The overall peak horsepower gain will depend on how well you have selected the modifications for your vehicle. Is this PCM harder on my engine or transmission? This PCM is actually safer on your engine than remaining with a stock PCM. When increasing boost, it is vital to match it with proper fueling to prevent the engine from running lean which can lead to performance loss and engine damage. This PCM keeps the engine properly fueled for better performance and safer reliability when increasing your boost and modifying your engine. Your engine will rev to near redline at full throttle shifts in performance shift, this is the only feature that may decrease the life expectancy of your engine, using a good engine oil and changing it regularly is highly recommended. This PCM is not harder on your transmission. The shifting is firmer but not abrupt, this minimizes wear and tear that soft shifts can cause on clutches and hard shifts can do on hard metal parts in the transmission. In performance mode, the
transmission will be more eager to switch gears back and forth, in doing so this simple act of shifting gears often may cause a decrease in life expectancy, however since the transmission is keeping itself in a lower gear more often and decreasing the strain it feels from high engine load in higher gears which increases life expectancy on converters and clutches, there is a balancing effect. What if I don t have performance shift, will I need to enable it? On 2001+ vehicles, your normal shift mode will be outfitted with a special shift pattern which hybrids the normal and performance shift modes found in 97-00 vehicles. This mode is essentially the performance shift mode with changes made to better accommodate daily driving situations; a little lower shiftpoints at light throttle, slightly softer shifting at light throttle, things of that nature. If you wish, performance shift is still coded within the computer and toggling has been activated. By hooking up a performance shift button, you will gain access to the regular performance shift mode and its full benefits.