Rwd 20v conversion

[bazz1984]

Hi all. Trying to simplify the vacuum system in a 20v. Want to know where to put the map sensor (old haltech e8) and the other labelled hoses

[bazz1984]

This is a silvertop
1 and 4 are the same and come of the 4th throttle body
2 goes to the fpr
3 I’m not sure
5 is to brake booster
6 is collects the itbs and I was going to use for the map

Cheers

[jondee86]

Struggling a bit with your pics, but from memory you will have...
- a larger curved tube out of ITB#1 and #4 that join together for the brake booster. Most people seem to find that just using the one nearest the brake booster works OK.
- The four little black tits (one on each ITB) are for the evap system. These are useless for a MAP signal.
- Use the tube marked #3 for your MAP signal. That connects into the common vacuum rail.
- If your regs don't insist on your engine having them, you can ditch the throttle opener and the evap system.
- If you want to have a proper idle speed control system, you need to keep the ISCV and have the output side connected to the BIG tube that is to the left of the tube marked #3.

Note: The OEM ISCV needs two PWM outputs from your ECU for control. If you only have one PWM output you can use a Bosch 2-wire ISCV. If you don't have any PWM outputs you are going to be stuck with cracking the throttle open to set your idle speed.

Maybe that helps

Cheers... jondee86

[bazz1984]

Thanks jondee. I was hoping you’d see this lol. Seen your reply’s to 4age and just wanted to make sure I got it clear in my head. I do plan on running a charcoal canister so I assume the evap stuff just connects and goes into that?
There is also a tit that comes off 4th itb is that any use? And the 3 you recommend for the map does it need a 1 way valve? Cheers

[jondee86]

The 20V evap system has a small ECU controlled solenoid valve under the throttles. The ECU opens this when the engine is running above some rpm threshold so there is manifold vacuum to draw the fumes out and into the four ITB's vis those little black tits.

I've never worked out how to modify this for an aftermarket ECU. My car runs a vented tank without a charcoal cannister. Maybe just use a wire tapped into the fuel pump circuit that opens the valve when the engine is running and closes when the engine is off ?

The MAP sensor hose connects direct to the common vacuum rail spigot. If you have a in-line pulsation damper knocking about, you could insert that in the line. Looks like a one-way valve but just has foam inside and you can blow thru it either way.

Can't think what else would have hooked up to the 4th ITB... maybe the throttle opener servo ? Have a read here as there might be something useful... http://club4ag.com/forums/viewtopic.php?t=21153

Cheers... jondee86

[AE3SGTE]

^ what he said.
I found this site very useful
http://www.my-acoustic.com/Car/vacuu...39;_vacuum.htm
http://www.my-acoustic.com/Car/vacuu...cuum_lines.htm

[LittleRedSpirit]

Jondae, your Adaptronic has a purge valve control system, and you just wire it up and you have control over tps vs rpm opening of the valve. Its likely a Haltech will do the same.

Map sensor goes to 3.

I used to just cross connect the litle nipples under the throttles (6), or cap them and use them for vacuum adjustments of the itbs.

Brake vacuum is correct. I used to just blank off the opposite side one with a bolt and sealing washer.

Big pipe by number three is good for idle control. I just used a gardening tap on a 20v but you can use a real idle control and it will be better.

I see no reason to ditch the dashpot, as its got a nice way of increasing driveability by closing the throttle gently, just make sure it gets a one way valve and vac signal as its designed to.

The fuel reg just needs the vac reference to do its job too.

[jondee86]

Good point about the purge valve control. I've never looked at it as I have never had a charcoal cannister. So if the Haltech has that function question answered.

I don't think that the throttle opener on the 20V functions as a dashpot. AFAIK it is there to hold the throttles slightly open to assist with starting, but retracts and stays retracted when the engine is running. I removed it when I ran ITB's on my 16V and had no problems. And the Adaptronic has a dashpot function that can be used to help the engine settle if necessary. Maybe the Haltech has a similar function ?

Cheers... jondee86

[bazz1984]

Thanks for the replies

Any recommendations for a tuner for this setup in Sydney?

[LittleRedSpirit]

Yeah I use the electronic dashpot function with my idle controller.

I guess youre right about the dashpot thing, if it has a one way valve on it as the epc suggests, then it should just keep vacuum and stay actuated once the engine is running and creating vacuum. However it does beg the question how does it know when the motor is off and it needs to crack the throttle once again for starting. The epc refers to it only as "opener" and no other description. Vague!

[jondee86]

Pretty sure the throttle opener has a "pinhole" to leak air into the servo and allow the spring to extend the actuator spindle after a short period (minute or so). The FSM says the idle speed should sit at around 2500rpm if the servo vacuum hose is disconnected and the nipple capped. So when it's working the opener gives a nice little burst of extra air on startup. Nice feature, but I find that having the ECU drive the ISCV fully open at startup does exactly the same thing.

Cheers... jondee86