Reg v's reset

[Scams]

Hi All
Around one month ago I asked the question would a xr6 fuel reg increase hp? The answer was no!
Resetting a ecu makes the car run rich is this correct?
If so my car makes more hp running rich after a reset but this could be because it had the time advanced when the cam went in. I will be getting a xr6 reg this week, I will see how it goes. I just thought people with the same mods might be interested.
thanks for listening

[Rollin]

Resetting the ECU will return the ECU to its factory settings, with no learned corrections from the 02 sensor.

Wither it runs rich or lean will depend on what you have done to the engine and the amount of wear and tear on the engine...you will probably find it will run rich at some rpm and lean at others.

Run the car as it is, with the stock regulator for maybe a thousand km of normal driving, then run it on a dyno. If the car is running lean at WOT (which in an N/A car is anything over probably 13.5:1) then put the XR reg in, reset the ECU and retest it in a thousand km.

While you are on the dyno you can gradually increase the base timing and actually measure the effect on hp and check for pinging, rather than just guessing.

If you just wack it in you won't ever know if the car is quicker with or without it.

I found on my XR6 that it picked up hp after putting in a Gli FPR, because it ran closer to the engines ideal AFR, so richening up a stocker would probably make it slower...

[EBIIXR6]

Originally Posted by Rollin

I found on my XR6 that it picked up hp after putting in a Gli FPR, because it ran closer to the engines ideal AFR, so richening up a stocker would probably make it slower...

Thats pretty interesting! Could be a cheap "mod" for us XR6 boys

[4.9 EF Futura]

Xr reg = higher fuel pressure = richer = ford already run quite rich = loss of power.

O2 sensor will "cancel out" any changes to fuel pressure when operating in a closed loop mode. Long term trims which are learned in closed loop can and will be applied to open loop operation.

A GLI reg in an XR will produce higher power after an ECU reset. Over time, the advantage will be eroded by the ECU's learning capabilities and applciation of KAMF modifiers onto open loop fuelling.

Moral of the story? Dont try and fool sophisticated engine management systems with simple tricks Base timing adjustments on TFI engines are exempt from this rule of thumb tho.

[Rollin]

I actually got the car dynoed with the XR reg in, and it was running rich.

Got hold of a GLi reg and put it on the next day, drove the car around for a couple of weeks then went back to the same dyno - showed an immediate increase in hp, in the vicinity of 10 or 15hp, then after playing with the cam and ignition timing found a few more.

First dyno was 179rwhp, final dyno with the reg and cam/ignition changes was 197rwhp.

I always go to great lengths to NOT reset the computer in my car (esp before and after modifying something, like fuel pressure for instance), because the learning process takes about 128 ignition cycles worth of decent driving to fully relearn. If it's already learned the current mods, why make it start again when you do another mod?

A while after I got that final tune I left my lights on at work by accident and flattened the battery. The car was an ABSOLUTE PIG to drive (stalling at lights, when the A/C was turned on), very fast rev drops on gear changes, hiccupping and surging, for a full week, then only a little less bad the following week - it took about 3 weeks for it to get itself sorted out, and breaking traction by just cracking the throttle open in first gear, no clutching required

[Rollin]

[img]hxxp://memimage.cardomain.net/member_images/4/web/208000-208999/208143_93_full.jpg[/img]

Intake air temp for the original 179hp run was 43*C, air temp 32, so fairly similar to the 'after tune' runs.



P.S. Totally irrelevant to the thread, but SURECAM FTW!!!