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Percy's Adjust-A-Jets

I saw an episode on Hot Rod TV where they were dyno tuning an engine and they used it. Seams like it would be great if your going to the track for a test and tune a lot or on the chassis dyno trying to tweak the motor for different set-ups but I'm guessing, once most of us find the right jets it wouldn't be used much anymore. So the cost may not be worth it if you won't be making a lot of changes. IMO
 
Maybe if the car does both street and track... the adjust-a-jets can be tuned accordingly. Open the jets for the track/performance and when you're back on the street relaxing/driving like grandma, lower the jet size for economy.

I've heard there is a carburetor kit for stopping the engine from stalling when gas swishes in the fuel bowls from hard braking... do you know where can I find that before I call Holley?
 
Holley's 'Trick Kit' has a lot of performance tuning parts, including the vent whistle and jet slosh tubes you're inquiring about. IDK if they have one for the Street Avenger carb. Check their site.

I wouldn't bother with an adjustable metering block or externally adjustable jets. The newer gaskets, especially those in the Trick Kits, don't rip and survive numerous maintenance cycles. IME, at the track, I can get the plugs to read right with two jet changes, if they're off. Once it's dialed in, it takes a lot of weather to change it. I never used external jetting, but did build a dial-a-pod and external pod spring plate to more easily service the vacuum secondaries on my 3310.
 
"hivewax" said:
Maybe if the car does both street and track... the adjust-a-jets can be tuned accordingly. Open the jets for the track/performance and when you're back on the street relaxing/driving like grandma, lower the jet size for economy.
Click to expand...
Like camachinist says, you can get it dialed in and then leave it. It would take some pretty big changes to effect it enough to need an adjustment again. Like a cam swap or open headers or something like that. As far as one set-up for the street and another for the track, I don't think you could really see a benefit for all the effort it would take.
 
Loren,

FWIW, I have mine jetted for the track and I see no ill effects when driving it on the street (albeit ever so rare).
 
Right now, I pretty much do aggressive street... I'd like the carburetor to be reliable, efficient, and perform at it's max. If funds are available in the future... God, are you listening? I'd like to upgrade to a Dart block, 8-9k max RPM, with a Jerico 4-speed, and bring it to the track frequently.
 
You don't need to spend all that EXTRA money to go to the track, hell....the way your car is now, is still better than the driver, I can guarandamntee that from my own personal experience!!
 
Are you talking about chasing the Poontang Cruiser??! :lol

Seriously, though, I drive the car a lot, so I know how it handles, brakes, and shifts. I need to get use to the new suspension...
 
Christ, twelve bucks for a piece of plastic? Last Trick Kit I bought cost thirty bucks and had two of them in it.

Jet extensions push into the main jets to keep them immersed in fuel. Usually they are used in a drag racing car on the secondary jets on a longitudinally oriented carburetor, with the vent whistle installed on the primary side. Can't speak for others but I ran low 11's and high 10's with the race car and never 'needed' them, meaning the engine ran fine without them, even though the car launched hard. If you're running a good chassis with a manual trans and leaving the line at 8K, then the money for a Trick Kit will be incidental in the extreme, so get one.

Here's a video which kinda outlines what I'm talking about..

Wheelstanding 1964 Plymouth Max Wedge Super Stock
 
I just ordered a vent whistle for the secondary fuel bowl, to stop the stalling when hard braking, and a pair of fuel bowl gaskets... and some roll bar padding to go along with it. That trick kit scared me off a little... :$$$
 
Normally, under hard braking, the secondaries are closed and the only metering going on is the idle/transfer circuit. IME, the purpose of the whistle is to allow atmospheric pressure inside the carb fuel bowl during acceleration, where the fuel might cover the vent opening and prevent proper pressure differential for correct fuel flow. Some folks install them on both sides, but I didn't do the secondary on the drag car because the fuel could pile against the back of the bowl, cutting off the whistle and causing a metering issue. The slosh tubes go on the secondary side to keep the jets from becoming uncovered on acceleration.

Circle track and road race cars might be different, so check around and see what others are doing.
 
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