14 replies to this topic

[yakkmeister]

Hello people.

Starters: '85 Civic, 3 door, single carby, 12 valve from Australia.

I have read heaps of posts re de-vac procedures on CRx carbys.
It would seem that the tiny little carby on my civic is no-where-near the same layout as the CRx carby. Obviously the vac lines and ports will be represented, but I can't simply copy the crxfanatic pictures.

I am possibly going to price up and install a twin-carby setup from a later model, but this looks a decent interim solution (which is funny, since twin carbs, if they happen are an interim solution to installing my gold motor.). Swapping out the carb for another type (say a webber or holley) is not an option. I *could* get a CRx carb ... but then that could be a problem, supply wise, and if I'm buying, I may as well get the twins.

So, after all that guffaw;
What is the theory of this 'de vac' procedure?
What is the benefit?
How do you do it? (ie: what ports to what sources)
Where do you find the ports and where do you find the sources?

(I'm going to be *trying* to find the carby specific data in my electronic manual too, so I'll post whatever *I* can find too)

Thanks for your time and help!

Edited by yakkmeister, 08 June 2005 - 07:28 PM.

[DarkHand]

The basic idea is to remove everything vacuum-wise except your distributor advance, secondary diaphragm, and float bowl vent cutoff. You connect all three to an available venturi vacuum port on the carb and cap everything else off.

Can you get any pictures of your particular carb?

And Welcome!

Edited by DarkHand, 08 June 2005 - 10:02 AM.

[yakkmeister]

The basic idea is to remove everything vacuum-wise except your distributor advance, secondary diaphragm, and float bowl vent cutoff.  You connect all three to an available venturi vacuum port on the carb and cap everything else off.

Can you get any pictures of your particular carb?

And Welcome! 

<{POST_SNAPBACK}>

Sure.

I'll try to get them tomorrow... well ... later on today.

I assume you'll want front, back and both sides.

[edit]
OK: My manual has no listing of the vacuum ports/hoses.
Any ideas where I can find this info?

Edited by yakkmeister, 08 June 2005 - 10:38 AM.

[zakats]

is it a 85 or a 89? make up ur mind
We CAN defeniatly help you on this one. First i recomend you search and check FAQ. Mr. noob you jp I was one not too long ago

CRX carbs are the came as civic carbs. but that goes if you have the same engine though they were all equipt with the same engines depending on trim and model year. there were the EW1,2,3,4,5 AKA D15a1,2,3,4,5 i believe no the a6 defeniatly wont work for you! lol
find out which motor you have and we'll help you from there.

welcome to the best civic website you will ever find.
--zak--

[zakats]

oh and yeah, my gallery on the left has pix of my de vac'd engine it was easy!!!

[yakkmeister]

is it a 85 or a 89? make up ur mind
We CAN defeniatly help you on this one. First i recomend you search and check FAQ. Mr. noob you   jp  I was one not too long ago

CRX carbs are the came as civic carbs. but that goes if you have the same engine though  they were all equipt with the same engines depending on trim and model year. there were the EW1,2,3,4,5 AKA D15a1,2,3,4,5  i believe  no the a6 defeniatly wont work for you! lol
find out which motor you have and we'll help you from there.

welcome to the best civic website you will ever find.
--zak--

<{POST_SNAPBACK}>

'85. It was a typo. Now fixed.
Then again, was there ever an 89 civic with a single carby?

Motor is a EW2. That's the number in the manual and on the engine number.
EN: EW21241518

The CRX carby's are different in that the engines offered were different, at least I'm shure thats how it is in Australia.

I searched. Believe me, I searched, long and hard. I understand the theory, but no the practice. It's nearly impossible to find specific details on this carby... Oh well, I have a few tricks up my sleeve still, so Onward!

I'm taking the car to see my brother, who may be able to find the lines also.
I'll get the pics and let you know how it goes. If i'm successful today (and it doesn't rain) I'll have before and afters.

At least there will be a resource for anyone else too povo to get a decent motor.

BTW: I have a PGM-FI motor (from a 1986 - and I'm shure of that - CRX/civic. A 'brown' or 'gold' motor. 1600cc I believe.) to go into this car when I have a replacement for it (I cannot afford to have no car at the moment). I rekon that'll get her going a little better than some de-vac'ing.

Edited by yakkmeister, 08 June 2005 - 07:43 PM.

[badpenny]

Then again, was there ever an 89 civic with a single carby?

Not as a production vehicle. 87 was the switch over year for the civic.

[yakkmeister]

Here is the Carby:

















Done.

I would like to reittorate this question:
What is the benefit?

My discussions with my brothers has resulted in serious doubs about the benefit of this type of mod.
For starters, it makes the car illegal in this state (QLD). I guess that means the coppers can go and take my car away... not sure.
It also means that cold weather starting is going to be severely comprimised. That could get mighty annoying.
It has been postulated that fuel usage will be increased. This is not a plus.
So, am I going to get any real performance gains from this setup?

Thanks all.

[badpenny]

Someone correct me if I am wrong but that is a 2 barrel and there are plenty of options for that at most performance garages that sell carbs. You already have no vac system. What we're talking about devac'ing looks like this, click here

[eldo]

That looks just like our Canadian Crx(and Civic) Keihin carb and intake. You have the benefit of quite a few performance modifications including using it as a blow through carb. Check out the post in the FAQ for the mods. http://www.redpepper...ODE=view&id=105

Edited by eldo, 09 June 2005 - 01:34 AM.

[zakats]

there was a carbed civic offered into the 90's im sure... just not un north america that i know of, but they did produce them. I believe that 1.6 engine you are speaking of is a ZC, which is pretty badass. All ew1's had the same carbs- same goes for the ew2's the ew's however were FI. as for performance.... it wont do much really although some say its a bit better still not much. Cold stars...shouldn't be too bad, mines great. Gas mileage...maybe 1-2 mpg. Were it my car and had the extra engine i wouldnt bother with it at all. If you were to keep that engine, go with a set of motorcycle carbs!!
--zak--

[yakkmeister]

Someone correct me if I am wrong but that is a  2 barrel and there are plenty of options for that at most performance garages that sell carbs.  You already have no vac system.  What we're talking about devac'ing looks like this, click here

<{POST_SNAPBACK}>

AH! that's all messy and dirty ...

Well, if there's nothing to do ... it's not going to be a problem then.
As for the 'blow through' thing, what's the theory behind that?
What makes a carby a 'blow through' ?

[eldo]

Someone correct me if I am wrong but that is a  2 barrel and there are plenty of options for that at most performance garages that sell carbs.  You already have no vac system.  What we're talking about devac'ing looks like this, click here

<{POST_SNAPBACK}>

AH! that's all messy and dirty ...

Well, if there's nothing to do ... it's not going to be a problem then.
As for the 'blow through' thing, what's the theory behind that?
What makes a carby a 'blow through' ?

<{POST_SNAPBACK}>

Blow through carby is when you stuff boost through it from a turbo. With a few mods with that carb (need an electric fuel pump and rising rate reg also.) , you can run 13 psi. If you have a black box with a few vacuum lines going to it , then you have some devac'ing to do- remove the complete box with all those lines.

[yakkmeister]

Someone correct me if I am wrong but that is a  2 barrel and there are plenty of options for that at most performance garages that sell carbs.  You already have no vac system.  What we're talking about devac'ing looks like this, click here

<{POST_SNAPBACK}>

AH! that's all messy and dirty ...

Well, if there's nothing to do ... it's not going to be a problem then.
As for the 'blow through' thing, what's the theory behind that?
What makes a carby a 'blow through' ?

<{POST_SNAPBACK}>

Blow through carby is when you stuff boost through it from a turbo. With a few mods with that carb (need an electric fuel pump and rising rate reg also.) , you can run 13 psi. If you have a black box with a few vacuum lines going to it , then you have some devac'ing to do- remove the complete box with all those lines.

<{POST_SNAPBACK}>

Ok. I have no turbo...
Also, that black box is the EPA gear, removing that caould cost me hafty fines, right?
In QLD Oz, that is.

My dad used to do mods like the one described above years ago, he's suggested he have a look and see what he can do.
I'll keep you all posted.

[zakats]

well there arent many ppl on rpr that can help you with AUS legal stuff. I for one dont know dick about it. like i said if you have a ZC laying around dont even mess with ur engine just drop in that beauty!