I've received a set of used IDFs from another member today and wanted some advice on jets.

These are 40 IDFs
Currently installed:
Venturis 32
Mains 130
E-tubes F11
Airs 200
Idles 55

I will be changing venturis to 28s due to previous threads/advice.

How are the rest of the jets in your opinion?
What might you change?

Target engine 2055 flat top, new AA heads (normal basic replacement ones) Webcams 86. normal mods. compression 8.6-9.0. Aftermarket SSI with Bursch exhaust. CDI ignition.

If you wanted a selection for tuning, what jets would you buy?

This will be final tuned with a wideband, but I'd prefer to be close at start up.

Who's your favorite source for parts? I will need carb kits and floats as well.

Thanks for your time

Rick

Rule of thumb on Main is 4 times Venturi so you’re right there in the hunt. I’d rather be rich on the main when under higher load or WOT. 55 idle also a good starting point.

You’ll be close enough to start / run / tune.

Pierce Manifold is a reliable Weber source along with CB Performance. Personally, I wouldn’t buy jets until I got it running and see where you’re at. Assuming you’re basically sea level I think you’ll be pretty close out the chute. Can use jet drills to enlarge a size or two if you have them. If you just have to buy a few Jets in advance, get some 50 idles.

IDFs run on idle circuit about 75% of time at light throttle / light load. More often than not, running slightly rich. the 28 vents are going to put a nice vacuum signal on the idle circuit at part throttle conditions so you might get away with a 50 idle and having the mix screws out just a little further.

What you have there will get you running and you can fine tune after she is running

Peirce manifold is a great source for weber parts.

With the 28s it will get you close. I'm thinking at the end you will have 120 or 125 mains and 50 idles, but you'll need the AFR to be sure.

I’m no expert, but I have a big cam 2056, and has 28’s with all the same jetting as you mentioned above. The only difference is that I have 50 idles…it runs like a top. This pretty much jives with all the other posts here.

Thanks for the replies!

So, I'll be getting
idles 50
mains 125/120
Airs 195/205 I've have lots of experience with DCOEs and the airs need to change with the mains most of the time. Maybe I'm wrong but Pierce's prices are great on these parts. $5 per jet is a giveaway in my book.

CB Performance has this kit.
https://www.cbperformance.com/product-p/6456.htm

Which does away with the aux venturis and replaces them with spray bars.

I'd buy annular boosters if they were available.
These do the same job but without the aux venturis.
Do they work? Does anyone have experience with these?

I'm planning on having the carb bodies and intake manifolds polished then anodized black and the motor will get "Darth Vadered" in its appearance. Different shades of black with yellow cad plated parts (as much as possible).

I will be using the Tangerine Racing linkage kit.

Air filters are the final hurdle. I'm looking for cast end plates (also black) and K&N style filters. Appearance is important here (flow is as well). Suggestions for nice looking air filter housings would be appreciated.

I think a few on here have a really slick crossover pod type air filter that mimics the 6 style.

EDIT: While the update kit is a cool fun thing to do, it doesn't seem like it is ground breaking in what it does, meaning you may or may not feel it with your butt dyno. If you are properly tuned that will net you the most power.

I would start with the 32s and see how it runs. Flat out the 28s loose a little steam. Swapping out the vents later is a pretty simple task. Get your best lean idle. Happy driving.

with the modifications you listed it could well run fine ,I leave the airs as they are like the vents they are easy to change later .
Do a search on here for Honda Goldwing air filters,IMO they are great alternative to K&N's and many report these work well and have reduced noise .

Thanks for the advice, Gents...

I'm getting extra jets, so I have options to make changes immediately and not have to wait.

I have 3 large bolt bins, 60 tray units, filled with Mikuni jets and junk.
About 75lbs of Mikuni junk. A friend who has a tuning shop has them on loan.
They do not fit Weber at all.

I'm probably going to buy 28s and 30s on the vents as I too believe the 28s are on the small size. All three will be tested/optimized as much as I can with the distributors I have (Mallory units, adjustable mechanical advance only, 3 of them).
I do have a high end 6AL that I will be powering it with, and it has a couple of timing adjustments in its gizzards as well.
I almost bought a 123 Dist in the group buy.
My thoughts then were "It's half of the cost of a MegaSquirt and the MegaSquirt is what I really want" so I didn't make that leap.
That distributor would make the old school carbs easier.

I'm going the carb route first; I scored some decent cores cheap and it's the quickest way to get a more potent power plant in the car. I'm trying to get it running ASAP as I am building it to allow my 84-year-old Father some seat time in a nice 914 before he goes "wheels up" for the last time.
Carbs are quick!

After moving up to a true digital ECU these carbs, fully tuned with matching tuned ignition system will end up in the for-sale sections of this forum. They will come with the extra crap I'm buying now.
They should look bad-assed when I am finished with them. Black and "gold".

Tuning with a laptop is like having every single jet, emulsion tube, accelerator pump options in a tiny magical box that is endless large and never empty.

Send me your address and I will drop you (4) 28 Venturis for you 40 IDF (FREE)
Too small, but for a stock 1.7/1.8 in my mind unless your goal is MPG.
Try the 32 in the 2056 its a good combo for daily drive and power/performance driving...mpg will be lower

I have some small idle jets too 47? i will check and see. I can include them too. for the same price (Wink)

Thank you, Sir!
I'll pay the shipping.

I'm getting parts together on the 2055 and it was going to be a winter project but I'm busting ass right now to make the puppy run/inspectable by September 15 Dad's birthday...

It's on its original 1.8 and the PO got it running with a brand new single progressive Weber in the center. They hadn't even run power to the choke or unload the choke which I did before I ran it. The 1.8 appears to be healthy; some further testing-leak down will prove this, but it sounded OK.
It did come with all the original FI. but it's been sitting dormant since 1989. Last inspection shows a date of 04/88. The FI will need full rebuild.

I was just going to make the baby Weber work for a bit, but I might try the IDFs on it.
They look like too much carb for the stock 1.8 IMO.

Really appreciate the offer rfinegan. I will take you up on it.
PM sent.
Thanks
Rick

I am running 28mm venturis on my recent 2056 with mild Elgin cam (built for carbs) she pulls nice and mileage is in the 32 - 34 mpg range. Couldn't be happier

I considered going to 32's, but why? I am only using this as a DD

This is a public THANK YOU!!! to @rfinegan

He sent me a set (4) of real Weber 28 venturis and REFUSED to give me his PP info so I could at least pay for the shipping...

YOUR TICKETS PUNCHED!

Need assistance, I'll do anything I can to help.
I'm a newbie on Teeners but on everything else (especially your new-fangled stuff) I'm a wizard and I have serious tools/info available.

I pay $2400 yearly for "Identifix" (my books) and they provide insider knowledge regarding repair.

I'm a cheap bastard and I'm OK with $200 per month for this powerhouse.
It's useless for 50-year-old cars but for the new junk it's priceless.

Got a prob, give me a shout!

The vents are ON EXTENDED LOAN. I will move up from them (I believe) and you can have them back anytime you want them Sir!

Best car forum I’ve ever seen. Made great by the great folks here.

Like you, I’ve had so many others contribute freebies to my project with no thought of getting paid or they have sold me parts at less than full value just to keep them in the community.

Really an amazing place!