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-   -   It's that time of the year AGAIN! (CIS) (http://forums.pelicanparts.com/showthread.php?t=185926)

tsuter 10-06-2004 04:10 PM

Quote:

Originally posted by Souk
Suter: My nose is out of calibration :) But if you want, I can tune that beast of yours in trade for a drive :D


OK Maybe, Have you driven cstreits 930? I want a little butt dyno comparison and I was thinking of letting him take it out.

To keep this OT, maybe a parking lot class in finding the CIS mixture adjusting hole for the newbs?

How would you set if it the car isn't idling anyway??? Jeeeez!! :)

This may all be idle talk (hahaha), I gotta get through immigration Friday or Sat or I won't be there......

Thack 10-06-2004 04:54 PM

Tim,

You can damage your engine with the non-vacuum WUR. The vacuum works at full throttle and helps richen the mixture by lowering the control pressure. It has a diaphragm that pulls on one of two springs so the upper diaphragm lets more fuel flow, thus lowering control pressure. In the 80-83 year models the freq. valve adjusts the mixture at full throttle.

Mike

MotoSook 10-06-2004 05:20 PM

Mike,

I ran my car for a long time w/o any issues, no pinging (even with 32 degrees total advance) and no hot running. I know how the WUR works, but I don't know how much more rich the vaccum makes it. Do you? Anyone have an LM-1 they'd like to loan me?

And the mismatched WUR has no problems giving me a rich mixture...just ask some of the people that have seen the flame balls out my tail pipe.

on-ramp 10-06-2004 05:24 PM

start-up is normal....drive 10 min to the grocery store, get back in , re-start, idles crazy at 2,000 RPMS!!!

every fall, winter same.

MotoSook 10-06-2004 05:26 PM

on-ramp...have you ever cleaned you AAR?

MotoSook 10-06-2004 05:28 PM

Here nOObs ":

http://forums.pelicanparts.com/uploa...1097112489.jpg

http://forums.pelicanparts.com/uploa...1097112520.jpg

on-ramp 10-06-2004 05:32 PM

Quote:

Originally posted by Souk
on-ramp...have you ever cleaned you AAR?
what does that look like? and where is it?

MotoSook 10-06-2004 05:37 PM

I'm just guessing why you ramp up to 2000...

But here is the AAR: (#36)


http://forums.pelicanparts.com/uploa...1097113040.jpg

MotoSook 10-06-2004 05:49 PM

A little more info in this thread regarding mixture and that O2 sensor.

http://forums.pelicanparts.com/showthread.php?threadid=137062

tdatk 10-06-2004 05:53 PM

Thanks Souk,
rt click copy paste.....save as "what I learned today"
; 0

Thack 10-06-2004 06:18 PM

Souk,

You can put a CIS pressure tester in line with the WUR and then put a vacuum puller on the correct vacuum line on the WUR. I'm not sure what values are achieved. I put on one of these earlier vacuum WURs on my non-vacuum car and I had to adjust my mixture because I heard some pinging. Just wanted to tell Tim to be careful. It would be interesting to put an air-fuel ratio meter in your car and see what happpens at full throttle. It would be interesting to see what happens in the O2 lambda car also.

Mike

mr.bch 10-06-2004 06:30 PM

I feel lucky. Just like last year, my 81SC started just fine this week and idled with only a little hunting. I am here in MI where the temps on Monday were IN THE 20s! There are so many CIS topics on this board, I think when I start having probs, I will just convert to EFI than trying to sort through them all :D

cantdrv55 10-06-2004 07:25 PM

Souk, it's like you read my mind or something. I live in Northern CA at sea level and last night I spent the night in Reno, NV (not at a Holiday Inn Express). My car would die at start up and at every stop light even when it reached operating temp. I knew it had something to do with mixture but couldn't understand why I suddenly had to mess with it when my car runs fine back home. I thought the thinner air in Reno was causing my car to run leaner than normal. I guess that did contribute but mostly because it's way cooler there in the AM and drier as well. Thanks for the timely thread!

MotoSook 10-06-2004 07:45 PM

Mike,

I'm working on some alternative inductions so an LM-1 is in my future for testing. It'll be a fun experiement; however, with the range of control pressure that the CIS can run with, the variability in WUR final pressure and the variability of idle mixture setting, I'm not too worried about lean issues. A day at the track didn't reveal any issues with my advanced timing, 89 octane fuel and idle mixture setting. I'll post the results of my testing.

Chris,

The CIS has some adjustability for altitude, buyt just like for temps..it's not enough. Glad you got soemthing out of this thread.

Tim Hancock 10-07-2004 03:47 AM

Thanks Souk and Thack!

Thack, I understand the concept of how the WUR on a 79 is supposed to enrichen the mixture when there is no vacuum due to tromping the pedal to accelerate. That is why I asked about a risk of damage running with the non vacuum WUR. I will proceed with caution.

Souk, you have proven with your similar set-up that damage is not likely. I will do a thorough check of all my CIS components at initial startup and I will probably set the mixture a little rich just to be safe.

thanks again guys!

Paulporsche 10-07-2004 04:40 AM

Tim,

I've found that setting the mixture so it is just shy of the point where the idle starts to hunt when warm suits my engine best.

Also, as I mentioned in your earlier post, while I never experienced any damage that I know of during the short time I had the non vac WUR, switching to the vac style helped w/ start & warmup. My gas mileage also seems to be better.

MotoSook 10-07-2004 04:46 AM

Quote:

Originally posted by Paulporsche
switching to the vac style helped w/ start & warmup. My gas mileage also seems to be better.
Thermo-time valve helped your start up and warm up. (I tossed mine a long time ago) ... and you got better mileage because you can get a way with running leaner and letting the vacuum richen it up when you needed it .. but that's from a lean setting...from a rich...who cares...I blow flame balls easy enough.

Tim Hancock 10-07-2004 04:46 AM

Thanks Paul, It makes perfect sense that a properly setup system will perform better and also get better gas mileage. I will temporarily need to compromise fuel mileage with a slightly richer o'all mixture until I can get the proper set-up.

Paulporsche 10-07-2004 05:05 AM

"I blow flame balls easy enough" -Soukhttp://www.pelicanparts.com/support/...s/beerchug.gif

BTW I have a non vac WUR (1980 an up) w/ only about 3000 mi on it if anyone needs one.

MotoSook 04-06-2005 09:01 AM

Here we go again! One more season.

Start-up and all the good CIS mystery starting to show up yet again.


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