Reporgraming and Hacking moderm PCMs

[racprops]

In the outside world, performance as it how fast can I go from zero to 60MPH is KING!!!

Even with the Tesla and other EVs often how fast they are is all important.

The fact that a super heavy Tesla can go drag racing and beat mayor full on drag racers is a odd waste its tech.

Meanwhile we have stock cars with 500 and 700HP.

I have never had any thing more powerful that 240HP. This is what my 03s are rated, both the Crown Vic and the Explorer.

I feel they are faster than I need. And I do enjoy winning 90% of all intersection drag races with them.

Yet there are tuners that can up the game, more HP more Torque and harder higher RPMs shift points.

If that was my goal I have a number of tunes to pick from. Lots of them.

And to be allowed to do this a license a legal permit costs only $50.00, plus a $300/$400. tuner.

BUT NO ONE does tunes for MPG, even though there a know number of things that can be done, tunes for better MPG and at the same time more power.

One loophole is that at WOT Wide Open Throttle all fuel injection programs go open loop and disregard the O2 sensors and run off the fueling/timing tables, so they are allowed to skip smog control during full power burns.

So a faster tire rubber power take off is allowed but not MPG, and almost everyone that wants a tune wants more power.

We have been racing ever sense we began to walk and run. And of course servivial has often depended on speed.


Rich

[Ecky]

I bought a tune for my ND Miata shortly after I got the car.

https://bbrgti.com/blogs/news/bbr-un...-mx-5-miata-nd

They have a dyno plot showing +21hp and +15ft-lbs, from a 1.5L, bringing it up to ~160hp. This engine has a 14.0:1 compression ratio and runs Atkinson cycle. They also advertise a fuel economy improvement. When I spoke with the tuner personally, I asked how it would impact fuel economy, and he said "not at all".

My guess is that additional power is made by running a bit less valve overlap (Atkinson cycle) and a bit less ignition timing to make up for thee extra air being let into the cylinder. If that's the case, I'd imagine it would be an economy loss under WOT - the two are mutually exclusive in this kind of engine. If they simply tweaked the ignition table, it would be a (minor) fuel economy gain.

Unfortunately, the tune is locked, and I can't see what they've actually done to it. I can only flash it, or flash back to stock.

[racprops]

Yes of course power improvements mainly happen at WOT: wide open throttle or at full power, most cars are tuned for the middle of performance.

This tuning gaves good performance with out over straining the drive train. Higher power places more strain on the whole drive system and can cause more ware and a shorter life of the car.

And there is a risk of more ware running lean and again most cars are NOT tuned for that either.

But it is also there. The fear is burned valves and holes burned into pistons. Lean can run hotter.

Rich

[Ecky]

Less rich cars run hotter - peak heat happens just lean of stoich. Any more lean and it runs cooler..

[racprops]

Originally Posted by Ecky

Less rich cars run hotter - peak heat happens just lean of stoich. Any more lean and it runs cooler..

When I was testing I had exhaust temp gauges, and I did not see any major temp raise.

At 16.4 MPG dropped off, power was down and I believe it started missing.

Rich