Jet size for twin holley 94

Tom's36coupe

Tom's36coupe

Well-known member
Well now that my friends at bubbas have my Mallory distributor tuned great its time to go back after my Holley 94 carbs. Charlie in NY rebuilt them and put in 51 jets with blocked power valves, I was trying to fix the poor running condition not knowing how bad my distributor was set up. Anyway I put in 56 jets which made it run somewhat better, now I know they are way too rich. Should I just go back with the 51 jets and adjust my timing to that? My cam is a Crower from the old Motor city flatheads with about 380 lift, pretty lopey it shakes the fenders for sure!
 
Power Valves Blocked?

As soon as I read that Charlie had blocked the power valves, the reflex to get away from this thread was immediate. Where are you going to go with that? Read several times that Charlie uses that method of controling enrichment which seems to defeat one of the best features of the design. Except for race engines, that method scares the heck out of me. Enrichment is an engineering problem that is often solved and sometimes not. No surprise that the larger jets compensates for the enrichment circuit loss. But twin carbs are not usually progressive and in threes or more, one carb can act as the lean one, with or without power valve and the others can become the enriched, extra carburation with fixed level of enrichment. There's got to be more to this story. Good Luck: Fred A
 
:)Tell you what Tom,i'll send you 2 4.5PV's and 2 prs of .046 MJ's , try them and report how they run then. If it cures your problem you can either pay me for them or send them back N/C. The jets may be still a little big [I have smaller]if your still on the rich side. I hope your not trying to run that progressive linkage junk. ken ct. If you want i'll send .048's instead,ken ct
 
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Tom's36coupe said:
Well now that my friends at bubbas have my Mallory distributor tuned great its time to go back after my Holley 94 carbs. Charlie in NY rebuilt them and put in 51 jets with blocked power valves, I was trying to fix the poor running condition not knowing how bad my distributor was set up. Anyway I put in 56 jets which made it run somewhat better, now I know they are way too rich. Should I just go back with the 51 jets and adjust my timing to that? My cam is a Crower from the old Motor city flatheads with about 380 lift, pretty lopey it shakes the fenders for sure!
Click to expand...
Tom, I'm running a 276 with a super dual, 94's, 5.0 power valves and 49 jets. straight linkage. This is the smoothest setup you ever see. Idels good with a track cam at 700-800 hundred, takes off smooth as glass, I'll wind it up to 4500, I don't feel like winding it any more. it's just a street rod, 40 coupe. 24MPH on the pike with a T-5 and 3:50 gears. Walt
 
Yes, 48 are the minimum size I have been able to use. 49 are better for all around use. The 4.5 or 5.0 PV is the way to go.
 
Was out of town until today, so have not been reading the posts. I know its an old topic to run pv's or not. My local guy who built my engine suggested blocking them and running bigger jets. Before Charlie did the new rebuild for me last year I had 2.5pvs and jets. The carbs were in bad shape though, warped and a few other issues. Charlie has me running very good now so I am a little afraid of going back to pv's as I had one that was broken and dumping fuel. Easy to take apart and put them in with smaller jets though, so might give it a try. Keep you all posted, thanks!
 
TOM; Take Ken's offer (non-better) and run the 46s and the PV 4.5, or 5.5, and We are going to ask you to start reading you spark plugs, read them now and after the new jets, after a short run (hi-way speed) and if the plugs are stark white, re-jet to 48/49 ?? I would be reading the tail pipe too.
Also how is the 36 geared, stock trans and 3-78s read end?
I haft to re-thing my jetting and today's so called gas we have today. In the 50s 48 to 51s on 3/8 by 3/8 in a very lite 34 coupe,and in 54 it was a 302 GMC out to 348, and Howard cam and 5 log intake with 3- 97s in a fordor Che%^y and a LaSalle trans, put you flathead boys back on the trailer. now I'am building my flathead with Merc crank, and all the dress-ups in a 39 fordor..... OLD...BILL... In my second childhood ...Tom; please keep us updated
 
My rear gear used to be a 4:10 now it has a 3.55. My plugs have been not too bad after about 10 miles on the highway. I do have a set of 48 jets , 50 and 51 but my two powervalves are old and not sure if they are any good. I found my camshaft card too, at .050 lift it has 383 lift and 238 duration for intake and exhaust. Not sure if that's wild or not. I will contact Ken or Charlie and get them to test......
 
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