found a hypertech PPIII on ebay for $135 shipped. not bad. i don't have my hopes up just in case it turns out like what i've read here and there. but it would be pretty cool if it fix my speedo and gave me some performance, hehe might just be getting this and the fastman shipped to my house around the same day . Next up plugs, wires, cap, and rotor.

 

be sure the seller didn't leave it vin locked.

 

nope the vin isnt locked

 

it should def fix your speedo, i use it on mine, as 4 performance, ill let you find out for yourself

 

if you use the programmer to fix the speedo and then you take the programmer off the truck so its back to stock, will your speedo go back to being off?

 

remember,, if you hear a "tink tank tink" when you smash the go pedal,, you'sa spark knockin..

 

I guess if you are going to experiment with
advanced ignition timing and leaner air/fuel ratios
{like the Hypertech/MoparPerf/Superchips PCM computer do to increase torque and hp}
then doing it in winter is best
because the colder air temperatures give some margin against
pinging and detonation.

The modified throttle bodies on Magnum 5.2/5.9 V8s usually
improve hp more than you would scientifically predict from the drop in flow restriction
- that is usually a clue
that the ported throttle body is affecting the reading of the MAP sensor
and also leaning the air to fuel ratio for increased power output.

It might be confusing to hear that 'leaning' the air to fuel ratio improves horsepower
but remember that the stock factory PCM computer settings run a 'pig rich'
11 to 1 air to fuel ratio so that they won't ping at full throttle on 85-87 octane
gasoline.

Usually highest horsepower and torque occur at an air to fuel ratio
of about 12.8 to 13.2
but the worst cylinder will detonate much easier at 13
than it will at a/f of 11
where the excess fuel cools the temperature.
An exhaust valve will burn easier
and the interior of a catalytic converter will melt
more easily at a/f of 13 than at the safer 11.

Remember with 8 cylinders
it only takes the worst one cylinder
...which might have a partially plugged fuel injector
... or a spark plug that misfires every now and then
to have a detonation that blows a hole in a piston top.

Headers and low backpressure exhausts
also lean the air/fuel mixture
by clearing out more exhaust gas
and therefore letting in a bit more fresh air.

Sunoco sells a 95 octane super-premium
that doesn't have ethanol in the mix
but not all stations have a pump with it.

If a gas station sells it in your area it is a little extra insurance
on the days when you intend to let it rip and run full throttle.

 

thats every day

 

Correct me if Im wrong but isnt speed calculation done from the rear differential tone ring on 98s? or is it just 98.5

My 98.5 had no speed calabrating issues.

 

You are correct (98+). The PCM counts the pulses and generates speed/mileage data from them given a predetermined tire/gear combo. You have to tell the PCM that you've changed something. My speedometer reads about 2 mph low from just a tire change (285's from 265's).