weber carb conversion and backfiring?

[zoe60]

My fuel pump is stock. No regulator. I tried one at first but realized I did not need it. Just junked up my engine bay. I checked my fuel pressure about two years ago and it was around 3. An Escort carb may be better built. I have one I never used and it is heavier if that means anything but if you just paid almost $300.00 for a Weber it seems kind of silly to throw in the towel now and switch carbs unless you are rich! My Weber worked out great. I've been daily driving it for about 3 years now and it has never let me down yet. Reliable and fun to drive. Not a race car but it will keep up nicely. Light years ahead of the original carb. It ran OK but it was slower than poop! Realistically, if your car is like mine you will lose a couple of MPG but the power is worth it.

[zoe60]

Thats doesnt sound kosher with the jets. I know there are different style jets. That is I had gotten jets that the heads were different. Some have the head that is the same diameter as the thread body, and some had a large head, bigger than the thread body. I wanna say the large head were made by holley and the small heads were Weber. I know I prefer the small head jets.
Also the corrosion you speak of, inside the carb sounds fishy!!!
I forget, was this carb from Weber direct, or from Redline? I know the Redline are new carbs for sure, I dont know about the Weber Direct carbs.

Its good you found the fuel line issue, as it WILL cause problems at sometime when the line collapse's.

Make sure they didn't mistakenly send you the wrong jets. They did that to me once. They replaced them right away though.

[bravekozak]

A member of the kia pride club says that a Simota air cleaner will fit stock carbs as well as others.

[zoe60]

you know brave u sure post a lot but I have yet to see a full on pic of any of ur cars what are u hiding?lol

With his special intake I'll bet his heater won't work anymore. Maybe he added a barb for the heater hose somewhere.

[hugginsvilleH&A]

to be honest zoe , i want to make this work come hell or high water because i have so much invested in it already , i mean its brand new and carbs are pretty simple operation, i just have not figured it out yet, but i am trying , it has been a brain teaser for sure, and patience trainer, but i do like tinkering with things, i am thankful that this is not my main ride,,,,,yet,,, but i hope to get it to be my main driver

[zoe60]

You'll get it. One thing about Festy's is, you end up leaning a lot as you go, and there is nothing wrong with that! No one ever said it wouldn't be frustrating though.

[bravekozak]

Weber tuning.

Weber parts.

[hugginsvilleH&A]

Bk that was the one i have been following ,thats why asked about the regulator and why i put one on from the beginning. (alldata says the stock pump is putting out 23 psi) and its also where i got the 80% of operation comes from the idle circuit. what i did do was order me another timing light , i got 2 and both are dead, go figure. and i figured what they hay! i got an AFR coming also so i can see "what in the wide wide world of sports is going on in there" is lean or what? waiting for parts and my weekend

[1chrisapple]

That wideband will deff get u pointed in the right direction

[zoe60]

I thought of another thing that could be wrong. Make sure your vacuum advance diaphragm is not leaking. Put a clean piece of vacuum hose on it and suck on it. It should hold pressure on either connection. If you can suck air through it, it is bad. Lack of advance when coming off idle will definitely make it run terrible. Unfortunately you can't just replace the advance mechanism. You would have to replace the entire distributor which is pricey. That was one of the first things I had to do on my car about 7 years ago. It got frustrating for me at first but stick with it. My car runs great now. Smooth idle around 600 RPM and smooth acceleration all the way up to as fast as I feel like going. I think most of the bad rap Weber's get is due to faulty installations. Air leaks will kill you and float level is very important too. Some day maybe I will graduate to fuel injection! I can't tell you anything about that!

[hugginsvilleH&A]

well this is the latest, installed the AEM AFR, put the carb back on with 140 mains and 70 idle, everything ran fine BUT when adjusting the idle i could bottom the mixture and it would still be idling, so its too rich, afr was around 11,,, put in the 65 idle jets things ran ok but was down below the 1 turn to bottom on the mixture adjustment screw , afr was around 12 at idle , when accelerating it was between 13-14.5,

should have stayed here but no figured i would try the 60 idle jets to get the idle mixture screw to be in the right range,,, so what i got was afr of 10.5-11 at idle with the mixture screw set at the preliminary of 2 turns out , so i adjusted the mixture screw back in to lean it out some,got the afr to 12 ish and the damn thing started the backfiring thru the intake AGAIN, wth

so i went back and put the 65 idles back in even tho the afr is stating a rich condition the whole time. got the afr back to 12 ish on idle and would rev ,afr at 13-14.5, BUT when trying to drive it, backfiring so bad its undrivable

I had checked to advance back in the beginning of this thread to see if was operating properly, i may need to go back and see if it is a pin hole in it or something, do a leak down check of some kind, at this point i dont feel like its a carb issue , i feel like i have done everything i could possible do with this carb, i do know the afr has not shown any leaned out condition at all if anything it has shown a rich condition,only during the some transition say letting off the gas from acceleration the afr would jump around then regain steady readings,,,, unless of course i am reading things backwards, the lower the number on the afr the richer , right?

i set the timing to 12* with the advance disconnected as someone here had mentioned,( i had it at 8* before) still the same. i need to go back thru this again and see if i am missing something

i thought about maybe something in the tank restricting flow and starving the carb or something, but the AFR never showed it leaning out , so i dont really know where to go, what a pita this has been

hate to have to go back and do a original stock carb after i tore all that crap and plumbing out of it, that would be another pita trying to figure where all the vacuum lines went

open for suggestions, escort carb maybe next IDK

[drddan]

Huggins. I wish I could get my hands on your carb! Trying to figure out your problems without a "hands on" is tough!
There has to be something else going on IMHO!
Check that advance as described with a hose , or you use that vacuum gauge you found, on the advance. Make sure it holds vacuum.

According to Bravekozak, the vacuum advance can be changed, He switched to a single port vacuum advance on his disty. Ask him via PM, maybe he can help with that.
I sincerly hope you get it figured out. It is a PITA when ya cant find a source of a problem!

[zoe60]

I'm sorry to hear it, Huggins. Like Drddan says, I wish I could see it in person. Sounds like you almost had it!

[bravekozak]

The distributor comes apart. But, you need a puller. I choked when I found out the carb ignition control module inside the distributor was $90 from Four Green. I bought four extra jy carb distributors for parts.

[hugginsvilleH&A]

bk how do you test the carb ignition module to know if its good/bad? is it the same as the vacuum advance or just a PART of that system?

so when i had it revving at 13-14.5 AFR thats the range that is optimum right? what about idle? does it need to be a steady 13-14.5 all the time or just sorta in the ballpark? this AFR is new stuff to me