need info on ecu!

[deryll1]

hey guys, i am building a 16v dual carb. in order to do it the right way my engine builder told me about a ignition setup out of a scirocco 16v. the ecu suppose to have a vacuum hookup ?? what kind of ecu is it? it must be out of a a1 i guess....any help?

[cuppie]

He recommended that you get the knock-sensing ignition setup from a Scirocco 16v (can also use the same system from a Golf/Jetta II 16v (PL - 1.8 liter) car. Same box.)

The "ECU" in question here is the knock-control unit. The vacuum connection is for its internal MAP sensor (needed for its load calculations for spark advance.)
Do NOT use the knock box from an 8v car - the rev limiter is part of the knock box, and an 8v car has a lower rev limit than does a 16v.

[deryll1]

oh ok. thanks for the info. so what exactly do i need? sorry, but this is all new for me....
there is a guy selling a ecu,harnes etc out of a 87 rocco 16v. is this what i need?

[Rannoch]

oh ok. thanks for the info. so what exactly do i need? sorry, but this is all new for me....
there is a guy selling a ecu,harnes etc out of a 87 rocco 16v. is this what i need?

http://www.driversfound.com/scirocco...e/knocksensor/

I thought the rev limiter was built into the fuel pump relay?
Bypass that and it shouldn't matter if you get the knock sensing equipment out of an 8v or 16v car.

[TBerk]

http://www.driversfound.com/scirocco...e/knocksensor/

I thought the rev limiter was built into the fuel pump relay?
Bypass that and it shouldn't matter if you get the knock sensing equipment out of an 8v or 16v car.

There is an old link on that very informative web page pointing to an Earthlink addy I used to have. I'll see about trying to resurrect the info and repost a new link. Keep in mind, re: this particular thread; my 'page' was Knock Sensor Grafting for an RD (8V Golf II) motor transplanted into a Mk1 Scirocco application.

TBerk
PS, My recollect, at the time, was recalling the Rev limiting was related to the ECU, not the Relay. (I have no doubt the Relay could be involved, 'down stream' so to speak, but all concerns in that regard seem ECU related...)

[Rannoch]

There is an old link on that very informative web page pointing to an Earthlink addy I used to have. I'll see about trying to resurrect the info and repost a new link. Keep in mind, re: this particular thread; my 'page' was Knock Sensor Grafting for an RD (8V Golf II) motor transplanted into a Mk1 Scirocco application.

TBerk
PS, My recollect, at the time, was recalling the Rev limiting was related to the ECU, not the Relay. (I have no doubt the Relay could be involved, 'down stream' so to speak, but all concerns in that regard seem ECU related...)

I know that with VW Foxes of the CIS-E variety, the rev limiting was accomplished by applying/removing voltage to the 5th pin on the Fuel Pump Relay. Easily disabled by using the horn relay in place of the FP relay.
As to what generates the signal? No idea if it's the ECU or Knock Sensing Unit.

With a Digifant Fox, it is the ECU (of course, Digifant foxes don't employ knock sensing).

[deryll1]

thanks, the link was very useful if u guys have more....just post it...need input!