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Registered
Join Date: Aug 2003
Location: Denver
Posts: 1,242
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Chips from RPM Performance?
When I bought my car (1985 928 S), it came with a two chips from RPM Performance. What are they (besides computer chips)? What were they intended to do from an engine management standpoint?
I tried a quick google and couldn't find anything on what specifically they were designed to do. Anyone? Michael
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1999 996 C4 Cabriolet 1997 BMW M3 (Hail) 1985 928 S (Sold) 1982 SC Targa (Sold) |
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07-05-2007, 07:43 AM
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Join Date: Jan 2007
Location: SoCal
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I don't know them specifically, but "suspect" they are pretty much a copy of the Auto Authority type chips. The chips themselves are I believe just a normal eprom like a 27c32, one goes in the ignition brain to make the timing a bit more agressive, and one goes in the injector brain to change the fuel/air table. Factory settings in 85/86 were very conservative going for best MPG and lowest emissions.
Most people report a nice increase in power and responsiveness with the chips, but sometime you need to pull them to pass a smog check. Before plugging them in you should get a more informed answer on your specific chips first. Given how cheap a known good set of chips are these days I would get some that have been freshly burned and checked. BTW its not unusual for a new owner to find a box like you have actually contains the factory chips and the hot rod chips are already in the car.
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US 83 zinc metallic 5 spd, aka the nice car. Euro 85 black, 5 spd, the fast rough track car maybe car. SOLD Euro 84 red, AT, only car in garage in years, my parts car, soon to go last 7 years. |
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07-05-2007, 09:32 AM
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Great advice.
I actually only know what the chips are due to the label on the actual chips. I'm guessing that with a more aggressive timing, I would need to step up to running premium fuel. For now, I'm interested in fuel economy (this will be my daily driver (60 miles roundtrip).
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1999 996 C4 Cabriolet 1997 BMW M3 (Hail) 1985 928 S (Sold) 1982 SC Targa (Sold) |
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07-05-2007, 09:40 AM
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inventor
Join Date: Jun 2007
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I have those chips in my '86.5. The ignition chip gives the most benefit, the fuel adds a little up top, but overfuels somewhat on acceleration.
A good setup is the performance ignition with the factory fuel chip. If you are not driving too aggressively, you could use Plus, especially if you plug in the octane loop. The factory was conservative on the ignition because there are no knock sensors, and they were concerned about the quality of unleaded gas available at the time.
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POWERED BY PORKEN 1986 928S3 AT grandprixweiß weinrot #11951988 928S4 MT polarsilberm sw/grau #1023 liftbars.com porken.com S300s.com
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07-05-2007, 04:34 PM
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Join Date: Aug 2006
Location: Cincinnati, Ohio
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At this point in 928 development, you woudl be best ot get your hands on a Shark Tuner and write your own chip set. Then they are matched to your car and it is exactly what you want it to be.
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Kuhn Performance Technologies, LLC Big Gun: 1988 928S4 Twin Turbo, 5-SPD/LSD 572 RWHP, 579 RW ft-lbs, 12 psig manifold pressure. Stock Internals, 93 octane. Little Gun: 1981 928 Competition Package Twin Turbo, 375 RWHP, 415 RW ft-lbs, 10psig manifold pressure. Nikasil Block, JE2618 Pistons, 93 octane. |
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07-05-2007, 04:42 PM
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This is pure speculation on my part, but for a stock 85/86 928 and with some allowance for variation in gas quality, how far apart is a sharktuner chip and a generic chip?
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US 83 zinc metallic 5 spd, aka the nice car. Euro 85 black, 5 spd, the fast rough track car maybe car. SOLD Euro 84 red, AT, only car in garage in years, my parts car, soon to go last 7 years. |
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07-05-2007, 05:46 PM
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