was wondering if anybody's tried using an adjust-a-jet on your holley or demon? seems kinda cool idea but i've never seen them before just looking for some feed back

Thanks

Bump! I'm also interested in any real world experience.

Percy's Adjust a Jet, correct?

i have one of those on my 650 db pumper.it was used on my 340 and my 318,ive had it at least 10-12yrs now,had to remove the jets,add the plate,have to use there longer accelerator pump arm.keep in mind u also have to change the length of the fuel line, due to the distance between the fuel bowls being longer with this plate installed,thats only thing i remember running into with this kit.u can adjust the screw setting for more or less fuel,even with it idling,always worked good for me.they send a sheet with it for ball park jet settings.mike

I've always wanted to try these but that's the first good thing I've ever heard about them^^^^^^

They look like they would be a nice toy, but once you have your jetting dialed in, you usually leave it alone, so after that point the adjust-a-jet would be kinda pointless.

i only re-adjusted mine on real cool nights (50*) at the track,i moved it one mark on the metering block which was roughly 2-3 jet sizes more fuel.

Many, many moons ago I used them on my VolksWagon Beetles after I put hedders on them. They helped a little.

I've got a pair in my carb box; I used them years ago for a couple of track days until I decided to just settle on a jet size. I think they could be a good idea if you were changing elevations and were running things a bit lean.

i used to run one on my old 750 dp holley. at the time i thought it was a handy thing to have. my current 4150 series Demon has had the same jets in it for the past 4 years, maybe if i was looking for a record i'd change them but i'm only bracket racing so they seem just fine for my application.

I had a set I was going to use on a Proform carb I had. They wouldn't fit the proform metering blocks. I have a holley HP now, but decided on a jet size and sold the adjust a jets.

well thanks for all the input guys, I'm thinking they are worth a shot, It just seems it would give you more tune-ability, just my two

"In concept" I think it's a cool deal. What I'd like to know is how precision the jetting adjustments are in reality. And unless there are some "fixed" increments of adjustments to ensure consistent changes, it sounds kind of hit-or-miss to me to duplicate the settings.