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Thanks for the trip down memory lane.

dude, we're just getting started..
So time to do the build up but wanted to do some custom parts..but where will we find those parts..hmmm
Maybe a 45 year old toolbox..

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So the jets are 70 primary 76 secondary, so I whipped out my jet collection, and now we have 64 primaries and I moved the 70s to the rear
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I already discussed the power valves, on the left is a high flow valve, the right is a standard, I located a 4.5 in the high flow variety..
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I was able to locate a REO accelerator pump as used on REO trucks, this gives a longer pump shot when accelerating, and should help with the bigger than normal carb
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I also located the long type accelerator pump nozzle in the same size as the stock unit, this will help put the fuel in the center of the venturi, again to help with defeating any dead spots in acceleration, you can also adjust the pump cam on the throttle shaft to help with this.
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One of my favorite tools, is a piece of wire, there are a million and 1 small openings in the carb, such as these air bleeds, I run a piece of wire through each one, and also blow carb cleaner through all the passages to double check
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So since I was pretty merciless on the carb body when I bead blasted it, I decided to paint it to help protect it..this is a proprietary color..Ghetto Fabulous Red..
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When doing the initial setup on the floats, just make them level with the bolt bosses on the float bowls, fine adjustments can come later.
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The secondary float is a nitrofil, I don't trust those once they've been left to dry out, so one is on order..
before installing the baseplate, I always check to make sure it's flat, a file and some sandpaper will show up nay high spots, I also do this for the face of the metering block and the vacuum can for the secondaries.
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The vacuum can that operates the secondaries is very important, first you need to make sure the secondaries shut all the way, when you inspect the base plate, then install a new secondary bladder, the spring can be fine tuned to allow the secondaries to open faster or slower, I used a spring that would delay the opening.
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Once that is all done, the carb is complete and ready for install..
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so I have about 80 bucks in the carb
 
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A Carb.. Whats that!!!.. Would not know where to start!! never touched one! Lol... first engine was a 1.6L Golf gti 39 years ago!!!

people forget that old school fuel injection was a PITA and didn't meter as good as most carbs. I've had my hands on a few Bosch units. Did you know that was a Chrysler design in the 50s, but since gas was cheap and nobody wanted it, they sold it to Bosch...lol.
Every time I hear how old school American cars are I throw that out.
 

Mad Hatter

Gotta go Faster
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4,227
Santiago, Chile
I was tempted with a pair of double Webbers but back then, they were out of the budget range.... But the old CIS Bosch did ok. that little Golf did 0-60 in 7.5s... then again it only weighed 800 kilos....
 

JDee

Ancient Racer
1,797
2,001
Exp. Type
W2W Racing
Exp. Level
20+ Years
5 miles from Mosport
I had a Holley 700 something way back in the early 70s, it had vacuum secondaries and it was a nightmare of inconsistency, could never get the right spring in there, always either too soft or too hard. Solved that with a mechanical linkage to pull them open, which was great until the mechanical linkage stuck everything wide open one night. You get lots of flames and blown out mufflers and other fun stuff when you cycle the key to try and shut it down. Thankfully, those days are behind me.....I hope.
 
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In the V6L
You can certainly date yourself by knowing how carbs work. I have a pair of brand-new Weber 42DCOE's in the garage bolted onto an equally new Warneford BMW 2002 manifold. They're in the same box as the big tray of jets, venturi's, emulsion tubes and the other junk you need to make these things perform. The only thing I don't have is a BMW 2002 - I sold it in 1981!
 
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BMW 2002 a friend of mine had one with the wide flares on it, it looked pretty cool, did you know that BMW supposedly took some of that car's styling cues from the early Corvair? if you look at the belt line you'll see what I mean.
I worked on a Corvair as well, ran 11.90s, totally stripped out, single 4bbl, actually used big block Chevy Crane Oteva valve springs for the front suspension, since it only had about 1 inch of movement.
 

Grant 302

basic and well known psychic
You can certainly date yourself by knowing how carbs work.

"OLD" is a date? ;)

I think it's just sad that the young ones may never learn this part of motorsports.

Even for actually understanding how to tune a modern EFI car...I've leaned a LOT on my understanding of how carbs work to understand how to program specific parameters. It's not just hook it up to the dyno and O2s and hope for the best...or at least it shouldn't be.
 
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In the V6L
"OLD" is a date? ;)

I think it's just sad that the young ones may never learn this part of motorsports.

Even for actually understanding how to tune a modern EFI car...I've leaned a LOT on my understanding of how carbs work to understand how to program specific parameters. It's not just hook it up to the dyno and O2s and hope for the best...or at least it shouldn't be.
I agree - I fine-tuned my calibration on my supercharged 2011 Mustang GT and all the stuff I'd learned when I was "the guy that does the carbs" for a buddy's race team when I was in high school came back to me. Getting the mixture and spark right were the easy part - I spent a ton of time on tip-in and smooth transitions from one part of the map to another. BTW, the buddy I mentioned raced a Cortina out of John Hall's Car Craft in the late 1960's when John Hall was a Ford-sponsored driver in Trans Am. The Boss 302 race car was quite a machine.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
I just sent off a carb from my wife's Corvette for restoration this past week. Its 50 years old and original to the car. It starts and runs fine. Its a "Classic" Quadrajet" so the plugs in the float bowl are leaking and it can use a face lift.
I considered upgrading to a TB fuel injection system. Then I thought against it.
If you rebush the throttle body shaft holes, replace the throttle shaft and clean everything up, I should get another 50 years out of the carb. I also thought about painting the body of the carb a bright red.....but that's been done already.
I like working on cars with the generation Zero OBD system. Get in, listed to and feel how the car is running
 

TymeSlayer

Tramps like us, Baby we were born to run...
3,787
2,740
Exp. Type
HPDE
Exp. Level
3-5 Years
Brighton, Colorado
Back in the mid-seventies, I recall tweaking and adjusting the old carb weekly on my '69 Boss 302 which I believe came stock with a Holley 780 or something like that. Never did consider it a PITA but rather just something we all did to get your car running the best you could. Not sure what I tweaked more, my car or my girlfriend Lorraine (Sweet Lorraine) but I digress...
 
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I've built quite a few Q jets, some sidedraft carters on a 54 Corvette Blue Flame 6. My neighbor growing up held half of the NHRA national record for C modified (or something) 59 Corvette with Carter WCFBs on it. Later on he owned a Pro Stock Camaro and put Grumpy Bill Jenkins on the trailer around 1971 at the Gatornationals.
Those were great times.
 
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The floor pan mod.. I hate having to climb under the car at the track, so I normally do this on my cars to check vital fluids. Some sanctioning bodies require a full pan, so you'll need to make a cover for it, but in my care they let you get away with metal tape.

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It's the little stuff that makes you go crazy..I was able to remove the fuel injection throttle linkage, pull the cable out, shorten the cable shield, then drill out the cable stay, solder it back to the cable shield, and then run the cable back through it..about 3 hours work.
THEN..came building the throttle bracket

This was the second attempt..

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Installed showing the cable stay

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All together

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Worked on this hog all day, I can barely walk, but if this video uploads thank Pete Desisto…
Yes, I know there's an oil leak...tomorrow (or maybe the next day depends on the meds..everything is hot wired at the moment anyway so there is a ton of tidying up to do).

stand by....first start up, eyeballed the timing and dizzy drop..
 
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