grats corey sweet

 

read the last part he already has the 1st spot

 

It is very hard to draw accurate generalizations about an entire product capabiliy based upon a hand full of individual experiences

Back when I first approached David about the idea of incorporating the reflash in with the Buschur Staged packages I canassure you that there was no way it would happen unless there was results to verify that the reflaszh had an advantage over the SAFC. Even way back then in the infancy of my days as a reflash tuner the reflash was able to make significant improvements over a SAFC in the power band, tq and smothness. Of course, I owe a lot of what I know about tuning these evos to the tips and tuning recomendations shared with me by David in the course of working on those original base flashes and in the course of many subsequent dyno tuning sessions over the past two years.

Over time my skills have improved and lately I have been finding ways to make huge power on pump gas. The stock ecu is a most complicated device and the longer you spend working with it the more you understand about how it works and how to make more power.

As a result of the significant advantages of the reflash it was adopted as the PRIMARY tuning method for the Buschur Staged 1 -4 upgrades for the Evo.

Not only has the reflash proven on multiple occassions to be superior to a SAFC on the old Buschur Dyno Jet dyno it has continued to be superior on the new Buschur Mustang dyno. At this point, we are not talking about one or two examples - we are talking about dozens and dozens. In fact, David has posted on more than several occassions that in Stages 1 - 4 the reflash can achieve results almost as good as the AEM EMS.

BR350 serial # 1 with on board ecu controlled boost control went 12.7 and that package maintains a original factory cat.

When David informed me of the situation there in Las Vegas, I decided to take some action to correct the misconception.

To set forth in a nut shell why the SAFC can not produce as good a result as a reflash we need only examine the nature of the SAFC itself.

The manner in whcih you tune an engine with a SAFC is by manipulating the MAF sensor signal to trick the ecu into thinking there is less load.

A MAF sesnor is a device which measures load on the engine by metering the air flow.

By electrically reducing the level of the MAF signal (OR increasing it) - the SAFC can make crude A/F ratio corections

As the stock EVO fuel mapping - (BOTH MAPS) - is overly rich - almost all SAFC corrections are NEGATIVE adjustments

The problem is that when you reduce the LOAD reference signal to the ecu the result is that you make a simultaneous FUEL AND IGNITION mapping change. The un-intended result of tricking the ecu to see a lower load is that it interprests this reuced load by running MORE ignition advance.

With less load you have less cylinder pressure and you can get away with signficantly greater ignition advance

The stock ecu maps have significantly greater advance numbers at LOAD ranges 10 - 12 % lower than stock boost levels. The result of a - 10% SAFC setting is not only a leaner A?F ratio but also much more timing.

As the stock factory ignition timing is already really more than most modified Evos can tolerate on 91 octane fuel without experiencing knock, when you add more timing the result is more knock.

The ecu quickly reacts by starting to pull ignition timing a little bit with every pull. After a few short minutes you wind up with a ignition curve which is rough, unsmooth and will have zero ignition advance or in some cases negative timing.

If any of you guys running a SFAC doubt me on this - take any generic OBDII scan tool and log your ignition timing which the ecu is running. Do a nice 3rd of 4th gear pull from say 3,400 to red line. As I like to say it is what it is.

retarded ignition timing and lean a/f = high egt - lots of engine mechanical stress through increased knock activity and thermal load and reduced tq

There is no doubt you can sqeeze out some power with a SAFC tuned evo on the dyno, however the fact remains that it is a really crude and ineffective way of doing so,

Way back in the day - when I was the first Evo 8 to run 11's in April of 2003, I was using a SAFC and qucikly discovered that by using a emanage and having independant control over ignition timing I was qucikly able to smooth out my ower band and add huge gains in TQ

These discoveries are all of course ancient history and yet there is a whole grroup of people who swear by SAFC

With a reflash, A/F corrections have NO effect on the ignition maping

The A/F for both the high and low octane maps are set directly as is the ignition mapping

Thus the tuner can set exactly the A/F and timing that is desired

By being able to independantly and seperatly adjust these very important parameters a really smooth and knock free tune can be achived

As for Dyno Flash ALL my custom tuned road tunes are set up to run with a total absense of ANY ecu induced knock ignition adjustments. This means that the ignition maping is set up to run with a almost total absence of any detonation with the fuel the customer is using at the time of the tune. This is done for two reasons, #1 its less stressful on the engine mechanically (detonation is a very violent and destructive force and takes its tool on rod bearings and pistons) and #2 it makes for an amazingly smooth car to drive. There is no bump in the power band or pulling of timing.

The concept is such a tune is quality not peak power - especially when dealing with 91 octane fuel.

I state as a FACT that ALL SAFC tuned cars are in a state of constant retarded timing through knock activity - (unless they are run on race gas only). This is not a good way to run a car.

There is no way to escape the reality of these facts.

Aditionally the SAFC is limited in that the ecu has two main maping settings, low and high octane. With the SAFC you are ALWAYS stick on the LOW octane map.

You cant properly set up a saftey measure for poor fuel with the 2nd map inside the ecu with SAFC

You cant take out the fuel cut or alter the rev limietre with a safc

You cant control bost with a safc either

 

i see. give away a third spot al
currently 2nd fastest in vegas with a stock turbo

 

Additinally I note that if you look at the 107 case studies I have posted in my section of the forums you will see that an evo should make TQ at least equal to or greater than the whp

in your signature you list figures which show significantly impaired TQ

While you can make good whp numbers with the SAFC and even get a decent track time in the narrow power band you drag race with the reality is that the car is dead below 5,000 with a SAFC tuned car and not a lot of fun to drive (compared to a properly reflashed car)

 

member Cremo03 on these forums had a 20 G tuned with a custom Dyno Flash road tune - the car was a animal on the road. His engine was 100% stock and he did not want to risk any damage so we limited his boost to 25 psi. There is more power on the table.

He made an easy 369 whp and 357 tq at the AMS dyno day.

The 20G is a great turbo

Seriously - you guys in Vegas should consider the alcohol injection kit.

First you can run a lot more boost and a more agressive tune with a total absense of knock

Secondly the alcohol dranatically lowers intake charge temps which is a huge advantage in the kind of heat you guys encounter

 

well, when would you consider coming down to vegas

 

we had one guy who was gonna hook it up but never did. I would like to see it ran. I just don't want to be the first to run it.

 

So does this mean everyone is gonna back out of the tune this month and wait for a flash? I'd love to get flashed on a dyno, but don't have it in the budget right now since I just bought a house.

 

I know that for a fact. We seen that on Coreys car, the stump puller.

 

Does corey's car still have a flash in the ecu?

 

PM SENT

 

Yes he does.

 

...

 

I hope not.