Holley 1945 Rebuild

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Thugrich

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So @Saint Coty sent me his carburetor to rebuild. I've done a Chevy 350 throttle body and a Jeep 4.0 one before, but never one as difficult and intricate as this before.

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These were my initial reference photos before disassembly.
 
I threw all parts into an ultrasonic cleaner with evaporust and most everything brush right off.

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Once clean, I started knocking down the casting marks.

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I was going to paint the carburetor with Aluma-Blast like I did for my cast aluminum transfer case on my Jeep, but decided to polish it the best I could.

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Ran into a small problem, but figured it out! Accidently sprung loose the power valve piston and could figure out how to put it back, so I just used a center punch to drift the edges over to hold the retaining washer back into place.

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Looks great! I've had those apart more times than I'd like; aside from their being set up a little leaner than I'd like, I've had decent luck with the 1945 on my '65 Dart. Luckily, I found a NOS one a while back, and the only thing I've changed is to up the jet one size. The '74 model that originally came with the engine was so lean that I couldn't believe it ran.

You did the right thing staking down the power valve; I believe that's all the factory did.
 
Aaron65 said:
Looks great! I've had those apart more times than I'd like; aside from their being set up a little leaner than I'd like, I've had decent luck with the 1945 on my '65 Dart. Luckily, I found a NOS one a while back, and the only thing I've changed is to up the jet one size. The '74 model that originally came with the engine was so lean that I couldn't believe it ran.

You did the right thing staking down the power valve; I believe that's all the factory did.
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Is there any information you can give me about the jet upgrade? I'm definitely not familiar with the carb and was just following rebuild instructions. But if I'm able make it run better, that would be great!
 
The '74 Holley had something like a 58 jet in there, which is terribly lean. Everyone says the '74 carb is garbage, but I made it work with a 63 or so jet. My NOS carb is from a '75-'80 model, and it came with a 621 jet (which is a 62 on the small side according to literature). I changed that to a 63, but it ran pretty good on the 62. A 62 or a 63 would probably be your best bet. I drive my wagon in colder weather, and I have used my wideband O2 sensor on it, so I followed the numbers and the seat of my pants to come up with the best jetting.
 
So a larger jet doesn't necessarily translate to more power? I'm sorry, I'm used to throttle bodies. The only reason why I ask is because this is for my brother's 76 valiant and I'm not sure how it ran with the stock jet. Should I go ahead and swap it to a 62 jet regardless? My brother has little knowledge of mechanics and will rather send the carb back to me in the mail before attempting to swap the jet back to sock.

Thanks for being helpful, I really appreciate it!
 
No, a larger jet will only make more power if the engine is lean to begin with. If it's about right, you'll just use more gas. If it already has a 62 in there, you can probably leave it. If it is smaller than a 62, you may want to consider putting a 62 or a 63 in there, but that's just my experience. What is in there now?
 
Aaron65 said:
No, a larger jet will only make more power if the engine is lean to begin with. If it's about right, you'll just use more gas. If it already has a 62 in there, you can probably leave it. If it is smaller than a 62, you may want to consider putting a 62 or a 63 in there, but that's just my experience. What is in there now?
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Not sure what size is in there now. I suspect it's whatever came from the factory. It looks like it's never been rebuilt before.

Bugman said:
D shaped carb throat , not 74 carb, is that your carb ,looks like 77 0r newer

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I know nothing about these carbs, but from I could tell it's a 1945. Maybe enlighten me some?

It's also ironic that you talked about the D-shaped throat, because I had looked it over and saw nothing really in there that would cause for it to be designed like that. I had seriously contemplated rounding the edge over for easier flowing air, but didn't know what was going on under there.

Please forgive any of my ignorance, I'm a throttle body guy
 
The D shape changed the air flow some how,the effect was to make the mixture in the manifold more even and uniform. So air/fuel ratio would be more even cylinder to cylinder. On the slant some times some cylinders are rich some lean depending on variable factors. Stuck with that change till end in 87
 
todays fuel needs about 3 to 4 percent increase in area jet size. So post carb number, will know what was there, go up one jet size
 
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