rich5962

Update.....After much diagnosis time and some suggestions from others I think I got this solved. Had to do this off and on over the last week due to other commitments but finally got back to it today.

I also opened the nozzles to 0.025". This helped the accelerator pump flow to reduce the stumble. The nozzle marked "21".......well, wasn't even 0.021". It was much less.

This afternoon I lowered the float level. I took it down 3 flats, tried it and was a bit better, less dripping in the venturis. I have a old Holley Guide that states each 1/6 turn(CW) it drops the level 1/16". So I went a few more, and the level is now down about 1/4" from the bottom edge of the site hole. BTW, before was actually above the bottom edge of the site hole. When I unscrewed it originally, fuel came out so I thought I was alright, then I removed the screw and a lot came out. It was much too high from the beginning. I believe this simple error on my part had much to do with the problem. I think I was chasing a ghost.

I also found a problem with the right side emulsion screw seal. It was dislodged a bit, probably sucking air, so I reinstalled it with a tighter fit and I believe that helped also.

I ran it up, re-adjusted the emulsions for best vacuum and idle, about 1 1/4 turns out on each side, and it's much better. Minimal venturi dripping at raised RPM.

Also, I controlled the temperature for a higher overall run to about 180 earlier and reacted much better too. I think I have it solved. When the engine is run under normalized temperature in the engine bay with air cleaner and normal configuration, after a few final tweaks I think it'll be fine.

To all of you that took the time to help and guide me.......Thank You.

Rich

Critter1

Rich,

Sounds like you have a handle on the issue.

I don't know if you were using E10 fuel during your tests but if you are, that will create a serious flat spot/hesitation on acceleration, especially when using Holley carburetors.
E10 runs about one or two jet sizes leaner than non E10. Also, while using E10, the accelerator pump shot has to be increased too and I see that you have already done that.

Different seasonal/regional E10 fuels also change and can make the issue worse.

I've also learned that when using E10 in a Holley carburetor, the float level likes to be a bit lower than when using non E10.

DansYellow66

I was sorting out a few issues with the dual Holleys on my Cobra replica a few months ago (they mount backwards so that messes with the Holley recommended float settings). Several forum members told me I should run the floats on the low side and the engine would respond better. The Holley technical guys were speaking the company line when I called them and sticking with it - set them per our specs. (Ohh - they are backwards on your car? Well, still set them per our specs anyway.) Yeah right.

I set the floats on the primary side a little lower than the specs for secondary side. And I set the secondaries according to Holley specs for the primary side. Confusing but basically I ended up lower than Holley's specs. Seems to run pretty good as a result.

Glad you got it sorted out Rich.

emanusa1

ok, thanks for the insight and videos your doing a great job... Awesome sound out exhaust. Hang in there I know how frustrating it can get.


Ed.

rich5962

Good info for further tests, thanks.

I actually was using REC 90(non ethanol) on break-in and diagnosis. Yesterday I had to run E10 but it was 93 octane.


Thanks.....Sometime you have to throw the paper away and just "do it". You're right.
That's what I did for the squirter nozzle holes. Stock is 021", Some said go to 025". It worked.

Thanks Ed, When you get your 3 - 2's on that awesome car we'll have to talk.

TCracingCA

A stumble from excess fuel or air are perceivable in this case right at the instant of throttle movement as excess air. Excess fuel is just slightly slower! Always glad to see a guy jump right into finding the ailment(s). You are worthy related to being an owner of tools! I think we can patch you into the Holley gang!!!!!!!!!

Avispa

Kudos on the first rate detective work, Rich.

I'm still totally stunned at the sloppy manufacturing. Casting flaws? Mispositioned throttle blades? Dirt and foam bits in internal passageways out of the box? Sloppy tolerances on squirters? Who knows what demons are in the metering blocks? Good Gawd the Chinese do better manufacturing than that. My old 3310 may just get tossed in the trash for a nice, new Quick Fuel HR-780VS.

rich5962

Thanks, it sure was exciting.

The packer at the shipper made the error and the vendor sincerely apologized for their goof up and has done me well. But reflecting back, now I'm actually glad it happened and made me open them up. This because of the other manufacturing defects found, like casting slag and loose screws.

For the record, the throttle plate problem I thought I had on the secondaries was a ghost. They should draw air. Not a problem. F & R will draw air and will be part of the fuel circuit as the idle bleeds are below the throttle plates and the air bleeds feeding them are sucking air by design. The transfer slots aren't used as they are on the Primary. There is no real spec on the plates to bore opening and inherent in the design. Some open more than others. i spent hours trying to get them perfect, to no avail and discovered it just cannot be done.

Rich
p.s. don't get too excited next time..... Holley bought Quickfuel, and the other day I was told Weiand bought Holley. But I just found this too....
http://www.businesswire.com/news/hom....P.-Sells-High
I think we know what all of this means. It's ALL going offshore. We're screwed.

idle bleed (dribble) hole.....

pltmgr

I, too, spent a lot of time chasing the air flow in the F&R carbs as well. I believe my carbs are factory. The throttle plates have opposite bevels for a better seal. I loosened the throttle screws and wiggled the plates to minimize light shining thru and there was an improvement but the rear carb still flows more air than the front. I was chasing a multitude of other carb and ignition problems as well but it seems it is all sorted out.

Had an L89 as a DD back in the day but I don't remember how much air flowed in the F&R carbs

rich5962

That's exactly what was going on here too. I was misinformed about "NO-AIR" induced into the secondaries. I never posted this clip here, but this is the ghost I chased for a few hours.:ack I really thought that was it. I was very wrong.