Intake Butterflies

[89'ClubK's]

I need a diagram on how to run the vacuum lines correctly. ( I know it's been covered before!)I've been having problems with the butterflies staying shut. Would it be more beneficial to take them out? Thanks!
Modified by 89'ClubK's at 3:07 PM 9/21/2006

[dattodude]

Staying shut? Surely the control signal from the ECU is working.Test/Replace the solenoid valve that is controlled by the ECU for the Power valve.

Tell us more on why removing the butterflys is easier than fixing the solenoid valve of the vaccuum piping that helps control them.

Removing them is a lot of work.

Cheers,Chris

[bentvalves]

You'll lose low down for topend....what size turbo will you be running, whats the car for? Not hard to remove if you choose to do so.

[dattodude]

Of course.. if you have a Euro CA18 ECU, then the 4000rpm signal for the power valve might not exist...this is a recent topic of discussion.

[89'ClubK's]

I had to literally break the butterflies free. They were gunked up so much.I lubed them up, but then they started to stay shut once more. The car cuts out and stutters before it shifts at around 1800-2000 rpm. It is like that with each gear. I read that taking the butterflies out created more power and response. I was thinking of taking them out b/c I'm replacing the gasket in order to upgrade to DSM 450cc injectors. I'm using an BB - S14 T28/25, and the car is just a daily driver.The harness and ECU are both from Austrailia, but the engine is JDM.Which is the best route: take out the butterflies or find the diagram and try to attached the vacuum sources correctly?Thanks!

[biosehnsucht]

removing them won't do anything useful, if yours are so gunked up just clean em.

you know why they get gunked ? the previous owner(s) didn't mash on the gas enough!

since there is no fuel injected there in the secondaries, all that buildup is blowby/etc being pulled in through the pcv and if you never drive so as to open up the valves, they'll just collect gunk.

so, let this be a lesson to all - your CA wants some stompin'!

Float did a dyno test not far back showing that having them closed does make dyno'able differences down low.. on his setup, he found the open vs close crossover was at 3750 so he changed his SDS from 4k (stock switchover point) to 3750. But he has quite a few mods..

When you freed them up, did you totally clean them out? If you cleaned them up and they gunkd again, you probably have SERIOUS blowby or something else is really wrong.

[89'ClubK's]

I just sprayed lubricant on them to free them up. But I also haven't had the vacuum lines connected to it. I need the diagram. The car won't boost at all, and the gauge goes all the way lean before it shifts/ while stuttering.Fuel pump is good, FPR is good, Injectors good, Coil packs good.I believe they just need to open up under throttle. I need the diagram please, if anyone has one. Thanks!

[biosehnsucht]

if nothing at all is hooked up, then they should stay open. vacuum pulls them closed. You could just hook them straight to the FPR or something for a vac source, but when boosting there's a theoretical risk of blowing out the diaphram. Stick a check valve that prevents boost inbetween to solve that. This'll make it vary with vac/boost but not necessarily in any useful way.

The 'correct' way is more complicated, of course..

as I just posted recently in another thread:zerothread?id=94324

My writeup there is almost totally unintelligible and I've yet to get around to do anything better..

you can see visually the vac routing here.

[89'ClubK's]

VERY big help! exactly what I was needing. Not much info on the 4sp. out there, but this was perfect. Thanks!

[Zero260]

But I also haven't had the vacuum lines connected to it. I need the diagram. The car won't boost at all, and the gauge goes all the way lean before it shifts/ while stuttering.

if I'm not mistaken, even with the butterflies closed you should build boost, and if you're fuel pump and everything is alright, you probably have a huge vacuum(boost) leak somewhere.as far as running lean, that doesn't add up, with no boost you should run rich, if anything. maybe a huge exhaust leak???

[89'ClubK's]

I'm running open-downpipe at the moment. My car will be getting paint this weekend so I took off the cat-back. My buddy ran his KA-T for awile like this, so I didn't think anything of it, other than losing some back-pressure.

[biosehnsucht]

open downpipe = really screwed up scavenging/etc, not good for drivability or much else. Except possibly setting fire to dry leaves - careful where you rev.