TheSamba.com :: View topic - Jet source

Sun Dec 12, 2021 2:08 pm

I'm needing to do some tinkering with the main and secondary jets on my EMPI Progressive.

I'm not sure what type of jet to purchase. My "local" guy has a Kit, but he's hard to get to sometimes so I want to purchase some jets and get to them when I can rather than drove 40 min, buy the jets, 40 min back, then get sucked into a Honey-Do.

If I have several jets in hand and some time away from the Honey-Do's... I can tinker... Don't get me wrong.. the shop owner is totally cool, but.. I have limited time these days... sheesh.... sucks.

Sun Dec 12, 2021 4:39 pm

ebay,Amazon, redline, there's a multitude of places online.

there's gunna be the whiners about this next comment but my guess is they probably fun FI anyhow...
I quit buying jets years ago and drill / solder them. I also typically file or score the size off the jet and include a carb spec sheet with any buggy I sell or engine that has a carb go with it.
if your only rejetting one carb there's no point in having $100 worth of jets you won't use just laying around

Sun Dec 12, 2021 8:05 pm

I've looking at those sources, I just don't know what to call them. Or some specs to look for.. startin' from zero.

Sun Dec 12, 2021 8:57 pm

aircooled.net sells 32/36 progressive jets and will send them 1st class main. They also have a tech article on jetting carbs.

http://vwparts.aircooled.net/SearchResults.asp?Search=jets&x=7&y=15

https://www.aircooled.net/making-weber-progressive-dfev-work-aircooled-vw-engine/

Sun Dec 12, 2021 9:53 pm

vwracerdave wrote: aircooled.net sells 32/36 progressive jets and will send them 1st class main. They also have a tech article on jetting carbs.

D'OH! :shock: I completely forgot about them!!! So what you're telling me is I need.....

THIS!!!!
http://vwparts.aircooled.net/Main-Jet-Weber-ICT-Baby-Weber-DFAV-and-DFEV-p/73801.htm

Mon Dec 13, 2021 5:18 am

At least with a progressive you only need two mains, two idles and two air corrector jets and two emulsion tubes.

And you can usually pick from a range of jets for the second barrel with only small effect..

So in the end you only need one of each size and of each type... so its 4x cheaper than for a pair of duals...

Read the looong thread on here for ideas on what size of jets...

Mon Dec 13, 2021 8:53 am

cptcrusty1 wrote: vwracerdave wrote: aircooled.net sells 32/36 progressive jets and will send them 1st class main. They also have a tech article on jetting carbs.

D'OH! :shock: I completely forgot about them!!! So what you're telling me is I need.....

THIS!!!!
http://vwparts.aircooled.net/Main-Jet-Weber-ICT-Baby-Weber-DFAV-and-DFEV-p/73801.htm

And these-
http://vwparts.aircooled.net/Idle-Jet-for-Weber-DFEV-DFAV-Progressive-74403-p/74403.htm

Per the info on Aircooled.net-
Quote: With that out of the way, we recommend the following idle jet sizes for sea level driving for the Weber Progressive

Primary/Secondary

45/60 Idle

125-130/170-180

160/180

Drop the size "1" for every 1k' rise above sea level. So if you have a Progressive in Denver (5k') you'd need Pri/Sec idle jets of 40/55, but the same carbs at sea level would use 45-60.

Despite what you have read in "other" places, these sizes will result in the best running (cool) and stellar MPG. Use the main circuit for your power tuning! Read our tuning guide for further tuning tips, you'll save a fortune by buying the jets you need ONCE without guesswork!

Keep in mind that the idle jet/circuit is where you do most of your driving, even on the progressive carbs. The main comes into play higher in the RPM range after the idle and progression has done it's thing. Changing just the mains will not do much for overall fuel economy and power in a meaningful way unless you are wide open most of the time.

Mon Dec 13, 2021 1:39 pm

I've read that article. It's good. the only thing that isn't specified is the displacement of the engine he is referring to. I'm currently using a 1641(Big bore heads, Scat cam) until my 1998(?) is done. I had a 17XX in there before and the Secondary is 195, so it's coming down for sure.

Mon Dec 13, 2021 2:22 pm

I am too looking at re-jetting my overly rich Progressive vs. replacing the intake and going to a PICT 34 carb.

Does anyone know what jets/tubes for each of these 4 areas the carbs usually come with out of the box?

I'm curious to know what the numbers will change from.

Is it as simple as just removing the top of the carb to replace these 4 items?

Mon Dec 13, 2021 3:21 pm

The carb is also known as the Holley 5200 and Ford had their version also. As far as jet access, the air's and emulsion tubes are thru the air cleaner and the idle's are on each end. The mains are only accessible by removing the top.

Mon Dec 13, 2021 3:58 pm

RCP Phx wrote: The carb is also known as the Holley 5200 and Ford had their version also. As far as jet access, the air's and emulsion tubes are thru the air cleaner and the idle's are on each end. The mains are only accessible by removing the top.

You mean my EMPI 32/36F progressive mechanical secondary bla bla bla.... is also the same as a Holley 5200?

Mon Dec 13, 2021 4:04 pm

There are minor changes but most of hard parts like jets are the same. Example would be that Chevy/Ford both used coolant for the choke. Also if you get jets from them they will probably be labeled in "thousandths not mm". I started using them on my VW's back in the 70's because I had easy access to them.

Wed Dec 15, 2021 7:53 am

RCP Phx wrote: There are minor changes but most of hard parts like jets are the same. Example would be that Chevy/Ford both used coolant for the choke. Also if you get jets from them they will probably be labeled in "thousandths not mm". I started using them on my VW's back in the 70's because I had easy access to them.

I called a NAPA, Autozone, O'Reillly, and Advance auto. They're all totally lost. The NAPA lady said she'd need to call Tech Help and order them. Then told me she had been there 32 years... I would think in the beginning, they were selling more hot-rod stuff.

It's a shame that the "kids" behind the parts store counters don't know more than they do these days. I used to work at a shop and could tell a bolt was 3/4, or 13mm, or that X car needed a PH8A filter.... the times.....

Wed Dec 22, 2021 9:49 am

Just an update on this. For the 1641 config, I reduced the primary to a 130 and the secondary is down to a 180 from a 200 when I had the 1776 in there. That made a big difference. Still bogs a wee big, but not much. Carb heat fixed too, that helped also. Manifold isn't as cold as ice.

I'm continuing to hope and pray that my other block is good so that I can turn it into a 2000-ish (74mm x 92mm). Then it will be back to the 140/200 setup and go from there.