Any opinions on replacing the chip on my '81? I've never done it and am wondering if it's worth it. How much add'l power can I get out of it? What other changes do I need to make in order to make sure everything runs well? Are there any side effects that go with it such as over-heating or anything like that?

Thanks!!

 

Leos;

The opinions are mixed - from not worth it, to feels better.
If it was me, I'd spend the money on something else - mufflers,
or save for heads, cam, rebuilt, etc.

 

The computer only controls the mixture and response. You can achive much more with you $200 than the chip will give you. The computer wilol handle minor modifications with out changing the chip. Also rebuilding the carb will help too, if you haven't already done this. Removing the cat or replaceing it with a newer performance cat is a cheap hp mod. :cheers:

 

Thanks Adam,

Since you mentioned it, I'm putting Flowmaster mufflers, new SS pipes, and a hi-flow cat on within a couple of weeks. I'm thinking about replacing the chip in addition to it.

I also have a close friend who does engine work on race cars, so I'm thinking of giving him the engine next winter to do some head work. Not sure about this part though.

I'm trying to squeeze a little more out of this mouse.

 

Aftermarket chips will mostly affect the timing curve. That is, an aftermarket chip will give your a steeper advance curve and more total advance at WOT. They may also change the point (a little) at which the primaries switch from computer control (closed loop) to full rich (open loop). But there's really very little performance to be gained by changing the fuel mix via the chip. The '81 computer really is designed to improve fuel economy and emissions at idle and part throttle, when the secondaries are closed; then it simply gets "out of the way" when you put your foot down. The computer literally bypasses the closed loop system and cause the carb to become just like any other Q-Jet as soon as you put your leadfoot on the loud pedal. :D

The significant performance benefit of an aftermarket or custom chip for the '81 is in the timing curve change. If your engine and exhaust are stock or close to it, you probably don't want a lot more timing advance, because it will just lead to spark knock on regular fuel (or at least make it more likely). If you get some more compression, and are willing to pay for premium gas, you can tolerate more advance and the extra advance will probably make more power.... jus' my $.02... :D
:seeya

 

Leo,
As Gator said (Hi Gator - I'm up & runnin :D ). What I did was to increase the base timing. The ECU doesn't know what the engine position is & just increases the advance based on rpm (as far as I can tell), so you'll get more advance, although probably not the optimum curve.
To set the base timing make sure that you disconnect the 4 wire connector from the dist. while you do it.
:cheers: