H/W 5200 w/ PCV is rich, w/o is OK; Holley 2300 w/ PCV is OK

[Bort62]

What Distributor do you have by the way? I hope not a load-o

 

[Williboy]

The dist. is a standard dist w/ pertronix. I'll have to check my timing but last I check it was ok and I haven't done or had anything happen. The throttle is barely open. 2-3 full turns past closed.

Last night I was going with the same theory that something was blocking the idle passage way. Took the top of the carb off and blasted carb cleaner down the different holes to see where they lead to and to hopefully clean it out. Did notice that the air hole that leads to top of the primary idle jet. If I block it w/ my finger it decreases the fuel flow but also stalls out the car. Where does the idle circuit feed into the carb?? Does it also feed thru the emulsion tubes??? Or a seperate passage way???
Also to note, that the primary idle jet holder never screwed in as far as the sec. It stuck out 2 threads farther. I looked in the idle jet hole and it was clear, nothing was blocking it. I wrote another post about this. Wondering if I had the wrong jet, needing a fat jet used on some Weber DGVs. If the idle jet isn't seating correctly in it's port could it be drawing too much fuel??? Almost like too big of a jet.

FYI This carb is an EGR carb. It has three vac ports. One under the filter base labeled EGR, one to the side of the idle mix screw and one above the idle mix screw. I have my dist. vac adv to the one above the idle mix screw and the other two hooked together. I remember the instruction w/ the carb instructing this Tried mixing the hose up, but no changes.

Bort62, thanks for the offbeat humor. I need that after work. BTW, my wife often says it's my head up my hole!!!

 

[jamyers]

I'm pretty sure that 2-3 turns past the point where the idle speed screw contacts the throttle is too much: 1 to 1.5 turns is what it should be. You're up into the mains, so the idle circuit is just barely contributing instead of having full control. Something is screwy with your idle circuit, so that it's blocked or not flowing like it should, which is why the throttle has to be so far open for it to run.

I remember the thread about mixed idle jets...have you tried swapping them side-to-side? fwiw, mine are the longer ones on both sides (shrug).

 

[Bort62]

If you are drawing fuel out of the main circuit, then your throttle IS open too far by definition.

If your idle circuit is also plugged, then it won't idle when you turn it down and it will just die.

 

[Williboy]

Tried swapping idle jets every which way. The pri idle jet just doesn't sit in as far. I haven't pulled the carb off from the adapter flange in awhile, but from what I remember, the throttle plate were only open less than 1/16". Too far??

Thinking the other way, if the idle passage was blocked, and it could only idle off the mains, wouldn't I have to open the throttle/ idle speed to keep it from flooding??? Just a thought.

Any ways, I think something is blocked or messed up with the idle circuit. I have a weird feeling about that primary jet seating. Bad casting?? Anyone else have a pri idle jet holder stick out farther than the sec??

Here's a thought... Why is there an secondary idle jet on a progressive carb???

I ordered a Holley 5200 book a week ago, I would love to have it to see a cutaway on the idle pathway. Hopefully it will be here by the weekend.

 

[Bort62]

Again, I have never messed w/ a 5200.

But, here is what I would do.

Set the idle mixture screw somewhere around 3 turns out. That will give you plenty of fuel through the idle circuit.

Get the thing started and idling. Start turning the idle speed screw down until gas stops coming out of the mains.

If it dies - then yes, I suspect something is wrong w/ your idle circuit.

You still haven't told us what your idle speed is.

 

[Williboy]

I already tried the mix screw out 3 and speed scresw out 1 and if I remember it didn't run( i've messed w/ so many things its getting hard to remember all the things I've messed with)

I have tomorrow off so I'll get some vac and idle numbers. I'm also going to pull the carb apart and check that primary idle circuit closely.

Before I hooked up this O2 sensor, I thought the car was running great. A little bit of knowledge can be a dangerous thing.

 

[Williboy]

SUCCESS!!!!! Well kinda, I've made headway and getting closer. Got a late start today but I also received my Holley 5200 book (more on that later).

Tore the carb apart and blasted every orifice nook and cranny. Cleaned out the power valve, jets etc. Long story short, closed down the throttle plate, might of had debris in the power valve and reinstalled the original main jets and air corr jets that came with the carb.
By putting in the smaller mains and air corr jets I was able to start adj the idle mix screw. I think that played a big factor. Now in idle in drive getting 14-15 A/F and driving 30 mph 13-14 A/F. I still have some fine tuning to do but I'm much closer to where I want.
Right now I'm running;
Mains: 315/223 = 150/130 +/-
Air Corr. 195/165
Idle: 70/60
Pump: 40
I'm about 1 1/2 turns on the Idle speed and about 2 turns out on the mix. Idle Rpm 600 -700 in Drive
I think I might go a bit bigger on the idle mix which will get my mix and speed screws closer. Haven't had a chance to take it on the freeway yet either.

Once I get it dialed in I'll add my numbers to the spread sheet

The book is a great reference item. It's about 92 pages with lots of pics. It broken down by section, 5 -6 pages each; Fuel Inlet, Idle, Main Metering, Accelerator Pump, etc... Has a generic diagram and a specific diagram for each section and explains how they work. Let me know if you have any questions and I maybe email a scanned section.

Now I can head to Vegas with a clear mind

 

[jamyers]

...
Before I hooked up this O2 sensor, I thought the car was running great. A little bit of knowledge can be a dangerous thing.

Heh, I know just what ya mean!

But at least now you'll *know* that it's dead on (at least that's what I keep telling myself). :roll:

 

[Williboy]

Update on the O2 saga...
I've recovered from Vegas but still haven't received the strut rod bushings I ordered, so I'm hesitant driving it around but I did do a freeway run. With jetting as listed above I'm running pretty good w/ 14-15 A/F @ 60-70 mph. (Just by going up or down a slight grade you see a noticeable difference 13-15+.) At WOT I'm rich at 12-13. I want to swap the air corr jets around just to see what that does but I'm going to have to wait until my strut rod bushings get here. It was a little too much fun coming to a stop

 

[BIGREDRASA]

Before you start messing with the Air Correction Jets--which are attached to the Emulsion Tubes-- make sure the Primary jet is the smaller jet. You're getting Oh so close. Make sure you send me updated data for the Jetting Sticky.

 

[jamyers]

remember - air corrector jets only come into play at higher rpms. I only saw them affecting mine if I held it in gear and wound it up pretty tightly (no tach on a stock 200).

 

[Williboy]

It's been awhile but I'm back playing w/ the jets. I had to wait to get the correct strut bushings and then was out a week after sinus surgery.

Did a good test drive and am running these AFR;
Idle - 14 -15
Cruise @ 30 mph - 14.5+
Cruise @ 70 mph - 15+
WOT - 11 -12

Now the million dollar question is... What is the correct AFR??? I did some search and found two atricles by Ford Muscle http://www.fordmuscle.com/archives/2006 ... /index.php [url=http://www.fordmuscle.com/arc...w.fordmuscle.com/archives/2007 ... /index.php

The first says:
Idle 14 - 14.5
Cruise 13 - 13.7
WOT 12.5 - 13.5

The 2nd is:
Idle 14.7
Cruise 14.7
WOT 12.5

Which of these good numbers to shoot for?? I'm going to guess and say the 1st is for performance and the 2nd is for mileage(?) I think I'm really close to where want to be and could probably leave it here, but I can never leave "close enough" and before I go swapping jets again I want to make sure I know where I'm going

 

[BIGREDRASA]

First off, running lean at 70 MPH would make me very nervous. You really should not go any leaner than 14.7 under load, for sustained periods. Good way to burn a valve or holes in the pistons. What's worse, if your sensor is not telling you what AFR each cylinder is running, and the "15+" is an average, then your two end cylinders are likely much leaner, and at risk.

Further, I'm still convinced that you need to reverse your main jets, placing the larger one with the larger, or secondary bore.

Spreadsheet will be updated shortly.

 

[Williboy]

Hold off on updating that spread sheet. I'm still fine tuning the jets.

I did alot off research on AFR values and came up with a wide variety. I did a spread sheet and averaged up the numbers and the avg is:
Idle 14.2
Cruise 14
WOT 12.5

Depending on what type of car or motor people were tuning, It seems that for fuel economy go on the lean side, for performance go on the rich side.

While my numbers aren't too bad and I'm running good. I'm about running lean on the primary idle w/ mix screw around 2-2 1/2 turns and idle speed about 2 turns also. I still have a slight bit of fuel comeing out of my main jet
I reread the H/W Jetting sticky and noticed SixPacker post

2. The 5200 also has small hole at the top of the air horn that I believe is an idle air bleed. The DFEV has a boss for this, but it is not drilled. My 5200 had an 80 idle jet vs. a 45 for the DFEV.
So if you are having to use a huge idle jet on a 5200, you might want to try putting a little RTV sealant over the hole and use a smaller jet.

By placing a piece of tape over the idle air bleed my idle mix dropped to 11. I had to adjust my mix screw almost completely in to get it to 13. But the fuel did stop flowing out of the the main. I'm going to pick up a 75 and 80 idle jet and see what that does.

 

[kirkallen143]

I did alot off research on AFR values and came up with a wide variety. I did a spread sheet and averaged up the numbers and the avg is:
Idle 14.2
Cruise 14
WOT 12.5

Just jumping in here...there is really no set AFR value because some engines will not run at best at those set #s. Set your AFR to what your engine tells you it wants.
My engine will not idle very well at all with any AFR above 13.5:1, it likes 12.5 - 13.0:1. At cruise mine fluctuates around 14.0 - 16.0:1 and with the turbo I have to keep the WOT AFR richer at around 11.5:1.
I tried the "rule of thumb" AFR settings on this engine and it ran poorly, hesitated, denotated, ping, etc...But I can tell you this, the AFR gauge does make for a great tuning device.

Y'all have a good one.

Kirk

 

[Williboy]

Stopped by the Weber shop but the biggest idle jet they had in stock was a 70. (Same as mine) They sai they never have to go over 60 on their carbs. So I picked up a 50 and will try plugging the idle jet air bleed and see what that does.

 

[l3n]

Further, I'm still convinced that you need to reverse your main jets, placing the larger one with the larger, or secondary bore.

The secondary flows more at WOT than the primary, so I can't understand why it would take a smaller jet either. A smaller secondary probably contributes to the lean WOT situation. I'm by no means an expert, but I'm running a bigger secondary too.


Williboy: For what it's worth, the Weber 6 cyl jetting kit doesn't some with a jet smaller than 60. You might ask the carb shop if they're talking about 4 cyl applications or 6 cyl.

http://www.carburetion.com/Weber/weberpartsjetkits.asp

 

[BIGREDRASA]

Don't forget the point about getting too close to stoichiometric. If your readings are taken at the collector, then I don't see how you can get individual cylinder readings. With the log, running stoich will give you a rich mixture for 3 & 4, and a lean mix for 1 & 8.

 

[Williboy]

Bigredrasa, the AFR I posted were averages, the number does jump around alot. As Jamyers previously mentioned probably due to the log. I'm really close, I just want to get my idle down w/o having to adj the idle speed screw too much

I3n, as posted I think the difference in jet sizes between the DGAV and the H/W 5200 is the idle air bleed that is open on the 5200. That makes the necessarity of a larger jet. Just by covering the idle air bleed w/ a 70 jet, the AFR dropped from 14-15 to 11.