Rev. limit WBX Digijet

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fastback
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Rev. limit WBX Digijet

Post by fastback »

I'm looking for a way to modify the rev.limit for the Digijet (2,1 DJ engine).Making it rev higher :)
This is in the Digijet ECU and gets signals from the ignition.
Does anyone know if this is a separate circuit that can be modifyed or if it's in the ECU's EEPROM program.
I have read the EEPROM , but can't figure the hex files.....
Anyone have schematics for the Digijet ECU or links to where i can find it??
Guest

Post by Guest »

BOOM
Guest

Post by Guest »

and that is??

Engle 130 cam makes it wanna rev higher.
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Danborn
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Post by Danborn »

Thats why I' have made a Megasquirt for my wbx oval!!


Jesper
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Piledriver
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Post by Piledriver »

Ask John at aircooled.net if his chip raises the rev limit...

I'm waiting on UMS. I want closed loop PPP/ion sense, and intend to help get the latter working once the main "box" is working.

Still waiting for something from Delphi as to the coil-on-plug modules.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
mechano
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high reving

Post by mechano »

did you check the rotor in your distributor , it may have a rev limiter , I am not sure about the digijet but the L-Jetronic (early version of the digijet) did not have a rev limiting function in the ECU. Both systems dont control ignition , may be digijet limits high rev. by cutting of the fuel.
Eren
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Post by Guest »

Something happens at 5500 RPM ; it sounds like fuel cut,yes.
ANd it does it in my other WBX car's as well , so a kind of rev limit is for sure.it says so in the VAG repair book also.
The rotor does not have a rev.limiter.

I have also looked at the Megasquirt , but want to check if there was a way to use the stock Digijet.It works OK otherwise
I'll send john a mail!


Thanx guys!
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Piledriver
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Post by Piledriver »

Unless you have modified your WBX heads, I hear you will start floating valves about the same rpm.

That will be the real limiter.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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fastback
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Post by fastback »

I'll have to test that :)
Well the WBX has dual valve springs.
Som says the will work fine in the higher RPM's

Time will show.
mechano
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reving

Post by mechano »

and some people say (type4.org) that VW hydraulic lifters don't work well over 5000 rpm , this may cause smt. like valve floating .

PS:DJ engine has hydraulic lifters

Eren
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fastback
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Post by fastback »

The DJ engine has Hydraulic lifters standard , yes , but will be replaced by
the older NON-hydraulic Type 4 lifters , also because of the Engle 130 cam replacement.
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Piledriver
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Post by Piledriver »

I have no experience with these hydraulics at high RPMs, but I if you do a bit of searching, someone who has built a few HiPo wassers says the heads have issues... with the springs specifically.

Perhaps I was thinking of a more radical application.

I do know the max lift is somewhat limited: A stock cam and 1.4 rockers works, as long as you stay under whatever that works out to lift wise, you should be OK.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
mechano
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Joined: Thu Jan 22, 2004 2:09 pm

Post by mechano »

fastback,

Have you found out that If the digijet really cuts-off the fuel at 5500rpm , or is it for some other reason , did you try the wbx with solid lifters w130 cam and digijet ?
I am interested because I have a complete digijet from a wbx engine and planing to use it one day on my 1776 type1 engine . my engine would rev to 6300rpm with carbs , If digijet would limit it , project would be a failure ?
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fastback
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Post by fastback »

mechano.
I have not assembled the engine yet (i'm in the middle of a Turbo WBX project, so it's on HOLD).But i know it is a rev. limit with the digijet.
With carbs though...
A friend had a 2,1 wbx with dual idf carbs and went higher than 5500 rpm.

Aircooled.net offers a Chip that fit's the 025 906 022D ECU (which i asume is the DIGIFANT ECU??) that increases the rev. limit to 6500 + offers more power.



http://www.aircooled.net/new-bin/viewpr ... d2=fsi0009



But does it offer more power compared to the DIGIJET 025 906 021F ECU...?? THen if a Lamda i fitted you can use the DIGIFANT & the chip to get more HP and RPM....i'm considering this DIGIFANT + Aircoole.net chip ECU for my Turboproject
VW type 2 splitbus 2.1 WBX turbo
11.92@187.89Km/h.
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fastback
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Post by fastback »

I have heard that it is possible to change the Crystal that controls the CPU frequency .
Some one said to me that incresing the crystal by 10% it would also rise the Revlimit 10%
VW type 2 splitbus 2.1 WBX turbo
11.92@187.89Km/h.
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