Flat Change features in After Market - ECU's

[meshmesh]

Was with a mate on the weekend getting his STi MY03 tuned, and he told me about a feature of this particular ECU (U-tec) that enables perfect flat changes.. Im like yeh right, until he took me for a drive, and was "wow'd" by the experience, it felt like being on motor bike. The gear changes were so smooth you didn't get any jolting whatsoever, the rpm during changes which were done around 7500, did not fall below 5800-6000.

The way he explained didn't make much sense to me, but did sound convincing. When a normal car flat changes, the accellerator is kept all the way to floor, whilst you are changing gears, when this happens the revs fly back until you release the clutch and the car stays pretty much on boost.

The feature he has, apparantely cuts ignition somehwere in the process, which stops the revs from flying back up, during the flat change. The feeling was so addictive I wanted one for the GTR, but apparantley the ecu company "U-tec" only make them for wrx's. The gear changes were literally like driving a dog box, super quick & super smooth.

This ecu also has launch control, and I was thinking the flat feature was a by-feature of the lauch control function that cuts ingnition. Apexi make the Power FC Pro which has lauch control and wodering whether this feature could be achieved with the Apexi Power FC Pro??

Anyhow he hopes to run it a Calder this week, with the mods we're expecting a mid to high 11..

[Zombie]

My Link has these features, it is pretty cool. Only I am suffering problems with it not disengaging well after I release the clutch. I think it is due to a dodgy earth.

All it really is is a lower rev limit that is turned on by a clutch switch.

I think you can get a Jaycar kit, but I think they would be a little more difficult to set up.

Adam

[EnricoPalazzo]

Power FC pro has both launch control and flat changing features i believe. Is that what u are asking?

[meshmesh]

Power FC pro has both launch control and flat changing features i believe. Is that what u are asking?

Yes..that's what I wanted to know. Can anyone confirm this and are there any difference's in the Apexi Power FC Pro & the Standards version?

[WiZardOz]

Power FC Pro Spec infor from Greenline website

Power FC Pro Spec.CPU (for DRAG)

Only available for some car models, the Power FC Pro Spec.CPU has been designed for drag racing use. These units have two additional functions over the regular units:

Ignition cut used for rpm limiter - Regular Power FCs cut fuel feed when the preset revolution limit is reached. At high rpm, there is the possibility of knocking when the fuel is cut in high powered cars. The Power FC Pro Spec.CPUs cut ignition at the rpm limit to prevent the knocking that could potentially destroy the engine.

0km/h rpm limiter setting - Allows for the setting for an initial rpm limiter that is active whilst the car is not in motion. This allows for mainting a rpm level for consistent launches.

www.greenline.jp

[jaik]

A friend o mine who designed the BadBiki SR20 daughterboards has been running flat shifting in standard Nissan ECUs for nearly a year now. As stated above, its as simple as a switch on the clutch with other switches in between (in case you dont want it on). The switch then changes maps on the fly in the ECU. It sounds awesome and definately allows you to keep up a decent amount of power between gearchanges.

JK

[R31Nismoid]

7500..and it hold the car @ 6000rpm... mesh, if you change quick enough your rpm shouldnt drop more than about 1000rpm anyhow

[meshmesh]

7500..and it hold the car @ 6000rpm...  mesh, if you change quick enough your rpm shouldnt drop more than about 1000rpm anyhow

Agreed in the higher gears, though 1st to 2nd..is questionable. But what he told me is, as soon as you release your foot off the acellerator, you release the boost pressure build up. Wheras with his system, boost is always on cause his foot never comes off the accellerator. And just by the way it changes gears, you don't get that "momentary" jolting when changing normally, it's feels like a constant push in the back through the gears.

[Roy]

It doesnt sound as though the PFc Pro has that feature. i know the Autronic SM2 and Motec M8 have it.

Can you get your friend to do me a favour, what happens if he puts his foot on the clutch and changes gears over a period of 1 second then releases the clutch. Does the ignition cut work on an like a normally closed relay, so is dependent on the position of the clutch?

Or when the clutch is pushed in the ignition is only cut for a set (albeit very brief) period, so you have to calibrate the setup for the speed/aggression that you change gears?

Im not sure, most that i have seen set it for a fixed duration based on clutch engagement, are they all like that?

[meshmesh]

Hi Roy,

Just asked him, and he said it is basically an ignition cut set to a certain rpm, in his case 5700rpm.

[b2barker]

You can add it to any ECU including stock with this:

Flat Shift

This also explains how it works

[meshmesh]

thanks barker! ...

[meshmesh]

Barker.. just checked out that site, and wondering whether there are other comanies making something similar you or others may know of? Seems a bit pricey at $340.00 US

[EnricoPalazzo]

I think there is a similar product sold in NZ for around 300 bucks NZ. Search for a post on Anti Lag and i think it should be in there.

[EnricoPalazzo]

What would u do without me

Gizzmo Shiftlamp / Launch Controller >>

The Gizzmo Shiftlamp / Launch controller combines a fully adjustable shiftlamp with launch and shift control abilities. The shiftlamp has an operational rpm of 500 to 16 000 rpm with no need for additional pills or calibration.

The launch/shift function cuts the ignition at the desired rpm set by the user. In turbo application cutting the ignition increases the velocity of exhaust gases allowing the turbo to spool and generate boost without load. This results in boost being generated before launching and therefore allowing a vehicle to launch with considerably more power. The ignition cut is clutch activated allowing flat changing (the ability to change gear without removing your foot from the throttle). With the clutch engaged the rpm will pull back to launch rpm previously set by the user in order to avoid over reving, this results in the vehicle not coming off boost while moving through gears.

Launch control can benefit natural aspirated cars by giving a consistent launch rpm for best results every time and enable quicker gear changes through flat changing.

Features >>

500 to 12,000 RPM range

Full RISC Micro-processor design

Easy operation, 2 buttons (mode & set) & a three colour LED

No extras required. No knobs to turn, no wires to cut, no pills to buy and install and no interfaces needed

Fully adjustable Launch control, creates respectable boost in neutral

Full throttle shifting to retain boost between gear changes

Supplied complete with loom, relay and terminals etc

6000mcd light intensity

Visual confirmation on launch mode

Super small dimensions at 16mm OD and 120mm long

16bit counting resolution

Launch control can be switched on & off at the push of a button

5 wire design to reduce installation costs

NZD$330

http://www.gizzmoelectronics.com/products_...shiftlamps.html

[ferni]

will this stuff your clutch quicker like normal flat shifting?

[Bass Junky]

Say goodbye to your Cat converter and or motor

When you drop spark, raw fuel get's thrown through the exhaust, that pop that you hear when you get back on spark if the fuel igniting in the exhaust.....

When you drop power to your injectors, you drop fuel, big spike of detonation is possible as it leans out. What if you miss a gear and have to clutch again......

Just a thought.

[USRB25S13]

So I could use my standerd PFC and set the rev limit to 8K and then use an aftermarket ignition rev limiter to let me flat shift. Sounds like a plan to me.

[maximajim]

So I could use my standerd PFC and set the rev limit to 8K and then use an aftermarket ignition rev limiter to let me flat shift. Sounds like a plan to me.

It seems as though the FC datalogit will allow you to do it without aftmkt electronics.

[meshmesh]

It seems as though the FC datalogit will allow you to do it without aftmkt electronics.

Interesting, as I think SydneyKid, and some others who I can't remember right now, use the Datalogic with their Power FC's...