tri power holley 94 idle problem

I’m trying to dial in my tri power set up on my 302 for the first time and am having trouble setting the idle. I am using Holley 94s with progressive linkage. When I get the idle set at what sounds like about the right rpms you can just be standing next to it not touching anything and it revs up and then back down like the rpms don’t want to stay too consistent. I had read about how the secondaries have to have ****erflies that close really tight so before I put them together I looked at it with a flash light and the gaps looked good like just barely any light was getting through the gaps. When the engine is idling you can put your hand over the secondaries and feel vacuum though. Is this normal or should there be no vacuum? I wasn’t sure because I hadn’t blocked off the idle circuits so I didn’t know if that created vacuum or not. I was thinking about buying those 12 degree br*** ****erflies for the secondaries but I guess I would then need to block off the idle circuits. Any suggestions would be good let me know if I am doing something wrong. Thanks

 

There should in an ideal world be no pull at the secondaries...this maty be hard to acheve.
Loosen slightly without disturbing the staking. Shift and check for closest fit you can get in the bores. Ford actually considered them select fit---do not touch at the dealer level, discard and replace whole throttle if loose! Not very practical now...
Close actual idle hole by tightening needls. Leave off-idle alone for now...feed p***age open.
Bad fit at throttles would be a logical cause for varying idle speed.

 

I have done a number of multi carb set ups with 94's the secondary (end carbs), idle circuits must be eliminated to remove idle problems. For example Speedway sells 97s secondary bases but they don&#8217;t work on 94s and check any other factory multi carb set up the (dumpers End carbs ) have no idle circuits. Also your description sounds like it could be a vacuum leak, spray starting fluid around the carb bases, intake to head surfaces and Trans modulator and/or any other vac***e connection without getting in the top of carbs if it revs. It&#8217;s a vacuum leak.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

 

I could be off base but isn't the purpose of the angled "br***" ****erflies in the secondary for the purpose of sealing the bore closed but not sticking when activated open? I would not want the daunting task of trying to make an idle circuit on the end carbs as this would just cause an unnecessary headache for street performance(which I ***ume is your objective).
Get or make a base plate work with the carbs you have, to eliminate the idle circuit on your end carbs......OR.....get a set that will work. MY $.02

 

Years ago I helped a guy seal his outer 97's. We put a very light coat of oil on the plates, closed them, and painted the bores from below on one side, above on the other, (so as to allow the plates to open ) with shellac. The oil kept the plates from sticking shut till the shellac dried. Sealed
em right up, no more idle problems!

 

Bringing up an old post but in the same scenario, trip 94`s on a Ford SBF.
Hints, tips and advise appreciated.

 

If they whistle, Leak, Smell of gas... and dont idle properly... they are just fine... .... all three of mine do all the above...

 

I had six of those pesky leakers, and I would do it again.

 

Had the same issue on my tri power...spoke with Charlie price at length from vintage speed...my old cast iron bases were basically junk because I could not get the ****erflies to close properly. I ended up buying his new aluminum bases that had the idle circuits machined out of em and the ****erflies were tappered to be perfectly shut...I couldnt blow air through them...this fixed my idle issue. Ultimately for the secondaries u should not feel any pull from them at idle...hope this helps

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