I have a 91' Camaro RS. But its not what you guys might think. Its not a stock RS, its a lil modified i would say. I put in some 373 gears, flowmasters, Edelbrock Headers, hypertech chip, and right now its at the shop getting a remanufactured 350 engine put in.
SO its much faster than it once was, so its not your ordinary rs. Ok but my question is that, when i put in the gears, for some reason the speedometer would say i was going 80 mph, when i was really only going about 40mph. Then on the freeway i can only go about 80 mph because the speedometer thinks i'm going 130 and the government chip stops me from going any faster. Do any of you know why its doing this, and if its because of the gov't. chip , is there any way i can take it out? Thanks

 

Depends What Kind Of Setup The 350 Is. If It's Carbed You Can Put In A MSD Stand Alone Distributor And Do Away With The ECU. The Tranny Can Be Setup To Lock Up In Third Gear Automatically By Making The {A} Wire Hot And And Splicing {C} And {D} Together. They Also Sell Cheap Kits To Do The Same Thing. If Your 350 Is TPI Or TBI Your Not Gonna Be Able To Bypass The ECU. Sounds To Me Your Looking For Speed And Your Not Gonna Ever Get What You Want From A Computer Generated Timing Curve And Fuel Mixture. Fuel Injection Is Great But It's Only Gonna Pump What The ECU Tells It Too. Electronic Distributors Are Great But Why Not Have One Where You Can Adjust The Timing Curve Yourself. Computer Assisted Shifting Is Great .... For Gas Mileage. Only My Opinon But, Computers Are Great On A Desktop Not Under The Hood. Sick

 

it depends on what you want to do with your vehicle. If you don't mind drivability problems when the engine is cold or the humidity is high then carbs are for you. Simply put, no carburetor can do what a feedback efi system can do compared by cost. I have never seen a carb that you didn't have to tune to offset changing conditions. These changes require carb disassembly in most cases. EFI can compensate for most any change in weather conditions. Those that cannot be automatically compensated for by the ECM can be easily reprogrammed by PC or Laptop computer in just minutes without getting your hands dirty.

But carbs only cost $200 compared to $1000 for EFI system and programming hardware/software. Where are the savings? Well, $200 is just the initial cost of the average carb, new. Later, jet kits, gaskets, various diaphrams, and springs are required to maintain and tune carbs. Most efi systems have a highway mode operation in which fuel can be saved during periods of cruising that don't effect any other driving period. Personally, I have experienced a 4+mpg gain in fuel mileage utilizing such "built-in" features of GM EFI systems. Cost savings are self-explanitory, not to mention the time you save by simply sitting at a computer to tune your car instead of disassembling a carb.

What kind of features does EFI offer over carbs? Well, simply put: a carburetor just sits there. A typical GM EFI computer system can be programmed in the following areas:

Fuel Delivery based on MAP (Manifold Pressure), TP (Throttle Position), RPM, ECT (coolant temp)

Spark Advance based on MAP, TP, RPM, ECT

TCC Lockup characteristics based on TP, VSS (Vehicle Speed)

Highway Mode Air/Fuel Ratio based on MAP, TP, VSS, Time

Open Loop A/F Ratio and Power Enrichment Changes

Closed Loop parameters

Manifold Air Temp influence on timing and A/F ratio

Idle Speed based on ECT

Transmission Shift firmness and Shift Points (electronic automatics)

Cooling Fan(s) Operation besed on ECT, VSS

Trouble Code Parameters

 

ive done the same thing in my 91 rs its your speed gears in the tailshaft of your transmission. when you change your gear ratio you need to change that too. the gears dont change them selves when you swap the rear end they will do exactly what theyve always done but the transmission is moving at a different pace than the tires. notice your car reving hight at any given speed?

 

Apsolus is right, when you changed the gears you never changed the sending unit in your transmission. When your trans and wheels were at a 1:1 ratio everything was good, not that you've changed the gears its more like a .66:1 ratio. All you really have to do it get a new speedometer sending unit for your transmission then it will be fixed.