Which holley

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Jayro

Well-known member
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My Car
73 mustang baby blue with clevo 351
Hey guys,


Trying to accurately know what carby I’m running. My holley doesn’t seem to have the type of numbers most guys are saying should be on there.

Any ideas on this one
 

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I can't read them in the picture. What numbers are there? Can you provide a complete carb picture too please?
Ok cheers

So the numbers
FR
80457-13
0247

And maybe LS 4R203
 

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It should be a good carb for you engine. I don't see any point in installing a Brawler.

I assume you bought the car with the current carb? How is it running?

The street avenger comes tuned out of the box in a configuration that will 'work' for most applications and situations. From the box the jets are a bit 'fat' unless you are at sea level. Holley's are very tunable. There is a lot of good information and video's on how to tune them. You'll want to get a vacuum gauge or even better, a high quality AFR meter/gauge.

Another option is to take the car to an 'old school' speed shop that knows carbs and has a dyno. They will spend some time dialing the carb and the distributor in for your specific application. This kind of service used to run about $500 a decade or so ago, it's probably a bit more now.
 
FR-80457-13 is what Holley calls the LIST Number. I think the FR means Factory Refurbished.

The second number is the date code. Yours is 4 digit, so the first 3 are the day of the year and the last is the year of the decade it was made. 0247 translates to Jan 24, 1967/77/87/97/07 etc...

The document linked below contains many Holley List numbers. Your series ends at -7 on the list, but most of them have identical specs, so it still contains useful info. If your carb gets rebuilt, record the jet numbers, power valve number, accelerator pump squirter, and which secondary spring it has (might need to take a picture since the paint codes often flake off). Yours should have remnants of black paint at the small end....this is the stiffest spring and your engine may benefit from something slightly lighter.

I recommend a Holley Brand rebuild kit. If you need to do any tuning, get the kit with blue bowl gaskets or black, in a pinch. I, personally, avoid the amber colored ones....they have some sort of varnish on them that glues to the carb and is really tough to get off...they tear when you remove the bowl/metering block or plate.

https://documents.holley.com/techlibrary_carb_numerical_listing.pdf
 
I agree with the suggestion to not just replace the Holley "just because." Holleys are generally thought to run rich. While that may be true in some or even many cases, the underlying reason(s) for rich running are many. I hate to just attach a bunch of files and suggest you read the articles. But, the reality is that were I to spew forth what my thoughts are, in truth the articles in the attached files will touch on the same issues. The difference being I found several of these articles long after I had formed my own opinions, based on my experiences with Holleys. In at least one of the files the content is from me, not a copied article.

IF, and I do mean "if," there is any reason to replace the carb it would, IMHO, only be on account of a 600 CFM carb maybe being a little small, depending on your engine size and if it is stock or not. For that matter, were you to go to a larger carb there is no reason to not stick with a Holley. Although the articles attached do contain some good info, I will point out those things you need to be looking at carefully:

  1. Power Valve Protection Circuit for pre-1992 vs 1992 and newer Holley carbs
  2. Vacuum Secondary Throttle feature vs Mechanical Secondaries, and how that feature helps carbs that are otherwise "too large" adapt to engines that could use the ooomph of a larger size carb at higher RPM, especially with a built engine
  3. Correct wiring for the Electric Choke, 12 volts switched power. I have a YouTube video in this topic at:


I hope you are able to get a nice balance between the power and stability from your Holley after digging through all that info. And I hope you keep the members of this forum up to date on what you find and what you end up doing.

As an aside, if you do replace the Holley with a different carb I will not be offended or hurt. I am not suggesting there are not viable alternatives to using a Holley carb. I am only saying if you follow the guidelines and suggestions provided to you it is far more likely than not that you end up with a really nice running and performing engine..
 

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I agree with previous posts, it appears there is no reason to just replace your carburetor. What issues were you having with it that led the mechanic to say you need a new one?
If it turns out your carburetor does have a terminal flaw, like a bad casting, I would go with a Summit brand, which incorporates the best features of the old Ford 4100 carburetors and Holleys.
https://www.summitracing.com/search...s/part-type/carburetors?N=brand:summit-racingAnd, before I spent 5 or 600 dollars on a Brawler I would go fuel injection.
 
An 80457 is a fine carburetor. Unless you have a really modified engine and really need more than 600CFM, there is no reason to change it to a Brawler.
 
I have been running an 80457 Holley for 24 years. It has been pretty damn reliable. I used the Holley conversion kit to change it over to a 4150. This makes tuning the secondary's much easier and economical. The secondary metering plates are not that great to deal with (or to purchase $$). I am running #67 primary jets and #73 secondary jets and the mixture is not as we say "too fat" with that set up. As most of us have agreed on this thread: if it works just keep it and save your money.
 
Thank you all for the replies. So I mentioned to said mechanic that it’s running a bit rich. His reply was “for $850 (aud) we will get that Holley off and get a brawler on which are easier to tune, run a lot better and never need touching again”

Hey I’m with you guys if I don’t have to tell the wife we have another chunk of change going on the car then I’m happy 😂

Now he did show me a holley he had there that he had just replaced. he pointed out (sorry I’m not sure the correct name of the parts) that it had these items when you look into the barrels they were sitting horizontal but he said that’s **** they should be vertical. But when I read your guys replies tonight I decided to lift my air filter off and have a good look and the items he mentioned are vertical on mine anyway so.

Aside from his point of view there is not a real reason to change it. Car starts and runs great in the few months I’ve owned it so I’ll take your guys advice and sit tight for now.

Cheers
Jase
 
Quickfuel carbs (the Brawler in this case) are good carbs, and do offer a few small design improvements over older-design Holleys. They are also now owned by Holley. The improvements are mostly around tunability. I suspect the mechanic was pointing out dogleg annular boosters vs the older design that many (not all) 4150s and 4160s have. Those do offer some small added performance benefit.

However, I agree with the rest of the posts that unless you WANT a new carb, it's really not worth the expense. I don't know your mechanic, but suspect he just likes the Brawler because of the ease of tunability (and the extra business is probably an added bonus). As for "never touching it again" that's no more true than it would be for the 4160 you have now, assuming it is in good shape and only needs tuning. I actually run a Brawler on my 351c. I replaced a 4160 that was smaller (fewer CFM). I didn't need it, I just like the Quickfuel carbs more and wanted something a little larger. The reality is that there is no measurable gain for daily driving.
 
Carbs are not in my wheelhouse so to speak, but reading this post with interest, I would certainly agree that the old adage comes to mind. "If it ain't broke, don't fix it" or in the case, replace it.
I also think that your mechanic is fixated on the Brawler. Maybe the only Quick Fuel /Holley he knows.
Back story on my carb situation; When I bought my car, the original Autolite carb had been replaced with a Holley Street Avenger 670 cfm. The problem was it ran like crap. I spent quite a bit of money trying to get it to run better ( later proved to have a bad primary metering block from new), but eventually I just replaced it with another 670. Even that, while it did run much better out of the box, needed to be "tuned" for my engine. I'll not go into that right now. While I was considering a new carb, I researched Q/F carbs and looked seriously at the HR series 735cfm (4150) and the SS series 750 cfm, also 4150 based. However availability locally was a problem, but I could buy the Holley 670 SA. The 670 is more than enough carb for my engine build and once set up, it runs great.
 
The good thing about Holley carbs is they are very tunable, pretty much every component can be changed out or adjusted.
The bad thing about Holley carbs is they are very tunable, you can go crazy changing things out to get them to run 'perfect'.

But don't confuse 'perfect' with 'drivability'. You're not trying to knock a tenth off your 60 foot times. You probably just want a setup that starts easy, idles well, cruises nice, doesn't bog or stumble when you go from a stop to either normal or spirited driving. You're not tracking the car or drag racing every weekend. You probably don't want to spend a lot of money and time chasing those last 10 or so horses or tenths of a second.

So, that being said. You can do a lot with a holley by only adjusting a few things:
1. idle screws (adjust in/out for smooth idle)
2. power valve (get one that works with your engine vacuum range)
3. Jets (proper for your cruise on the primary and power on your secondary , which is why the secondaries are usually a little fatter)
4. Secondary vacuum spring you want one that doesn't bog the engine nor one that you can 'feel it come on')

Also, make sure:
1. The choke is adjusted correctly (not hard to do)
2. Accel pump is adjusted correctly (also not hard to do). Again, most don't need to swap out the cam or cam position
3. Float levels are adjusted
4. That it does open to WOT when the gas pedal is depressed all of the way.

Sure, you can mess with:
1. accel pump size
2. accel pump cams and positions
3. accel shooter sizes, types
4. metering plates
5. types of floats
6. the list goes on and on including crap folks do with a drill or piece of wire

But, in my humble opinion, you don't really need to do any of those things for a street driven car that has a reasonable cam.

So if you decide to dive into tuning your holley watch some videos on how to do it and stick with the basics. You can be pretty successful tuning with a vacuum gauge and a bit more specific with an AFR meter. Or take it to a speed shop with a dyno.

And don't confuse 'easy to tune' with 'easy to change'. Once the carb is set up for your daily driving situation you are done. Being able to swap out things like jets quickly only benefits racers or people that change altitudes a lot.
 
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