Holley carb ID help

[Bolt-Action]

Hey guys,
got a carb question, on my 67 w/440, there's a Holley 4bbl carb that I'm not real familiar with. I believe it's a 4165 or 4175 (?)
number is 7855 D082.
choke, vacuum seconds., spread bore, 650 cfm?, there's a metering plate (not block) on the seconds., single inlet, no external float adjusts., that's all I can think of to ID it, if I'm not mistaken, I believe these wre QJet replacements (?).
Is this carb worth rebuilding and using on a mild 440? Seems like it may be a tad lean at higher RPM's (?)
i was thinking of going with a 4150, but all things being equal, any carb properly tuned will be a good carb.
whats your thoughts/experiences with the 4175?
thanks

 

[rsd859]

I would email holley, they are really good at getting back with you rather quick.

 

[Bolt-Action]

I was just wondering if anyone had any real world experience + or - input?

 

[bm02tj]

Not sure but my book says it is for 1975-76 440 so it would be a thermoquad replacement

 

[72RoadrunnerGTX]

Nothing wrong with the 4165/4175’s, used them several times on BB Mopars over the years. However 650cfm on anything but a very mild 440 will hold you back. Here is a (universal) 4175 on a 400 in action. (Video, click on the picture)

 

[Cranky]

A small carb on a big engine doesn't go lean just because it's on a bigger engine....at normal operating rpm. It meters fuel based on air flow....but it can become lean at high rpm because the bigger engine can flow more air through it than a small engine. Up side is your off idle throttle response will be good and you can jet it up a little.

 

[Bolt-Action]

Good info guys, thanks.
the 4165's/4175's aren't a carb you hear alot about.
that would be my only concern, is that at extended, high rpm runs, it may be a tad lean for my needs, but it'd be snappy off idle for sure. Still thinking about using a 4150/4160, but haven't made my mind up.