I'm looking at freeing up some space and cutting down on wiring complexity by getting rid of all the fancy idle stuff on the back of the plenum on my silver Zed. The plan is to get rid of both the IACV & AAC mechanisms, blank out the hole in the back of the plenum behind the AAC mechanism and run a hose from somewhere in front of the throttle butterflies straight to the ballance pipe with some kind of adjustable restrictor in it. Obviously I'm not going to have the best idle from this but I figure if I set it slightly high it should be fine for my purposes. Any thoughts on this? Any ideas on what I can use as a restrictor?
Had not even thought of playing around with the butterflies. I think there is a bolt which can be used to adjust where the butterflies come to rest with the throttle cable loose. Blanking off everything and adjusting that may be the way to go. Thanks
I have seen the IACV & AAC mechanisms removed and a nylex garden irragation tap plumbed in it's place . It seemed to worked fine. Just looked different .
The issue here is going to be coming off the throttle, the engine will likely stall. This is the job of the AAC. If it's for a track car, no worries.
i've done it to mine mate and its been like that for a about a year now. i removed everything associated with the IACV and made up flat steel plate cut to size to blank off the hole. i just set the idle with the throttle cable and it sits on 900rpm easily. i don't have any aircon so i thought why not just get rid of the valve too. i can drive it around normally or flat out and it never looks like stalling.
You already have all that you need on the stock AAC. What do you reckon the the adjuster screw does? It's an air bypass. Dont try to use the butterflys to adjust idle. They are too big and just a small amount of movement can make a few thousand RPM of difference. Just unscew the soleniods off of AAC and blank off the holes. Then just adjust idle with the grub screw. IMO this getto fix is a waste of time as the idle will change with temp as well as a hundred other variables. You should pull the air con idle up solenoid off and block it, leave the idle control one in place and use whatever ecu you pick to run it. Like this
I'm hoping to end up with all the stuff on the back of the plenum gone and no electrical parts for the idle to simplify everything as much as possible. I'll keep all the bits somewhere safe for now and see if I can get the cracking thr throttle to work in a suitable controlled fashion, failing thatdoes anyone know of anything more suitable than a garden hose and tap to replace the grub screw set up in the IACV with? Failing that I'll see what I can do about simplifying the existing hardware as much as possible. Thanks all.
I am with Tekky on this, the idle control can help with idle across the whole range of engine variables. One thing not covered here is closed throttle response. When you snap the throttle shut a electronically controlle idle control can remain shut until the engine is below a set RPM. I am not sure about other ECUs, but the Link ECU i use I leave the idle control shut until 2500RPM, and fuell cutoff until 2000RPM. On deceleration both steps are very noticable. I found it is good for moving around the pits, get the car moving in first and let the idle control maintain the engine speed like some really really slow cruise control.
Fair enough, one more wire in the loom will not kill me. Also, won't I lose all my carecar cred if it does not stall 3 times whenever I try to drive it slowly around the pit area?
By removing the air con idle up system you lose a heap of pipes off the balance tube as well of lots of unnecesary wiring. Losing the back of plenum stuff shouldnt be an issue. By the time you have no EGR, IAV's etc you only have 8 bolts and some injectors plugs to pull to get it off. You have to have the idle control somewhere. Its out of the way in the stock position and only has 2 wires and a pipe on it. Not much of a worry. You still have to find a spot to put your boost pressure sensor for the ECU where it can sense both sides of the plenum. Or are you going to run a MAF? Or MAP ? IF you are going to use MAP, the balance tube is a great place for pressure sensor. The air temp sensor can be screwed into one of the spare holes on the plenum side. Boost pressure sensor on the balance tube. You can cut heaps off the balance tube you wont need. You still need one of the small pipes for the fuel pressure reg. You could also remove and weld up the smaller secondary pipe on the balance tube if the mood takes you. There is not much left behind the plenum to get in the way after you do all this. So you arent saving any complexity by dumping the idle control valve IMO. I havent finshed with mine yet. It may get more naked by the time I've finished with it.
Thanks, am most likely running a Link ECU which uses MAP but it's not set in stone yet. Your right about the IACV not taking up too much space without the AAC and associated piping, I was just caught up in the glory of removing absolutely everything from the plenum. This all came about at I had a little time to kill over the weekend and started stripping the plenum. With all teh under plenum hoses and such it weighs in at 13kg, rather more than I was expecting! Still, plenty can go. Probably not a huge weight saving the the over all scheme of things but it should make it much easier to work on things around there. If I run a catch can can the PCV bungs under the plenum be replaced with bolts to block them up? I'm sure I heard somewhere someone shaved half a kg of metal off the plenum getting rid of unused lumps and bumps where brackers used to go and such too. Also, I got a tie rod end remover tool.
LOL, I cut about 3KG off my plenum. There are heaps of lugs etc that can and ground off. ALL the piping underneath can go along with the mountng points and the steel pipes on the throttle bodies. I cut off the PCV bosses complete amd welded up the holes. I am not using stock injectors or fuel rail. So cut off all the injector rail mounts as well as grinding out the extra webs between the runners. Actually if you want em I have modded stock throttle bodies you can have gratis seeing I bought the bigger diameter ones from Z1. You need to have the catch cans plumbed back into the sump so you dont have to empty them. Suggest a TT sump and use the turbo return line entries to drain the catch cans back into the system. You get some extra oil in the sump as well doing that. Emptying catch cans is a PITA. They fill up real quick on some cars.
Modded how? If you've no use for them I may well find something to do with them. You've got a TIG welder don't you? Any chance you could be bribed to get rid of my PCV bosses some time? Good idea about the TT sump too, I'll keep an eye out for cheap ones in the for sale section.
I do have a TIG but I am crap at using it. Been paying for the gas bottle for 3 years and havent used it. I got Tom to weld the holes up. Could have a spare TT sump ( as well as the one on the engine) But was keeping to to modify with the oil trap door or I will probably buy the bigger one from Z1 and not use a stock one at all. So........... The thottle bodies have had all the steel pipes removed and extra alloy bits cut off. So if you want em!!!!
There's an engineer somewhere in Blegrave who specialized in aluminium stuff, might look him up. If you are genuinely not going to be needing the throttle bodies I'll grab them some time but it's not an issue if you have some use for them. How much would you want for the sump? Will be a while before I need it so I'm happy just to keep my eye out for another one if you wany to play with yours.
